100-ACRE IRRIGATION DESIGN

100-ACRE IRRIGATION DESIGN

Irrigation is the best way to ensure continuous food production with an ever-increasing population. However, when designing large irrigation schemes like a 100-acre irrigation design, we must take a lot of care when deciding the components to use to avoid risks of failure. Irrigation schemes of this size can use one type of irrigation method or two or more methods depending on the crops grown.

Water uses for different crops

Plants need water for growth and cooling purposes. It is essential to know the water use, why plants use water, and the factors affecting water use in irrigation. By knowing this, you can be able to avoid over-irrigation and under-irrigation. Crop water use entails two processes, i.e., evaporation and transpiration. The two processes are customarily combined and referred to as evapotranspiration. Transpiration is water loss through the leaves’ stomata, whereas evaporation is water loss through the wet soil or plant leaves’ surface. Plants extract water from the soil using the roots.

Evaporation occurs in the upper soil surface (depths of 3 cm to 5 cm). The evaporation rate is high during the initial stage of crop development, but as the crop grows, the canopy increases, offering shade to the soil surface. The shade helps reduce the evaporation rate in the mid and late stages of crop development.

Uses of water in plants

Plants use water for the following purposes;

  • To cool the plant by transpiration.
  • Photosynthesis – it is a process by which plants make food.
  • Transport of nutrients and organic matter.
  • Germination
  • Support system – plants achieve this by helping the plants’ cells remain turgid.

Crop water use determination

We determine crop water use by measuring changes in the soil water content with respect to time. However, the methods involved are tedious, expensive, and time-consuming. We use the crop coefficient and the reference evapotranspiration to quickly determine crops’ water use. The crop coefficient depends on the crop grown and the growth stage of the crops planted. Reference evapotranspiration refers to water use based on the prevailing weather conditions in an area. For instance, Crop water use is an important element when determining the water requirements in a 100-acre irrigation design.

Factors affecting the evapotranspiration rates

The following factors affect the rate of water use in an area;

  1. Solar radiation – stomata are sensitive to solar radiation. The amount of radiation affects how wide the stomata open, affecting water loss through transpiration. Solar radiation also affects evaporation rates. The higher the solar radiation, the more the evaporation rates
  2. Air temperature – plants use transpiration to cool the plant. Increased air temperature means high transpiration rates.
  3. Plant species – different plants have varying growth periods and water uses.
  4. Growth stage of plants – a fully matured plant will need more water than a recently planted crop. There are three growth stages of plants, i.e., initial stage, mid-stage, and late stage. At the initial stage, the water demand is low, and water loss is mainly through evaporation. In the mid-season stage, the water demand increases because of the flowering and fruiting of the crops. In the late stage, water demand depends on the desired plant conditions during harvesting. If you want fresh produce, the water demand remains the same as the mid-stage. For dry harvested produce, we reduce the water application to achieve that.
  5. Wind – the presence of the wind increases the evapotranspiration rate. The wind removes moisture from the air creating room for more moisture.
  6. Relative humidity – when there is high humidity, the rate of evapotranspiration is low. The water loss rate is increased when the humidity is low.
  7. Degree of surface cover – evaporation is mainly through the soil surface. A high degree of surface cover implies that the evaporation rate will be reduced.


pump

The pump house

 

The pump house in a 100-acre irrigation design refers to a building built to hold the components of the pumping unit. It is used to protect the pump from external conditions such as freezing. There are two primary water sources, i.e., surface water and groundwater. Surface water refers to water that collects on the ground or in streams, lakes, rivers, oceans, and reservoirs. The surface water is used to replenish the groundwater. Groundwater is water that collects in the spaces between rocks and soil. Groundwater is usually of high quality, but it is best to measure the amounts of iron and manganese in the water. Measurement of these elements is done since they can block drippers or sprinkler nozzles when the concentration in water is high.

Components of a pumping system in a 100-acre irrigation design

The pumping system in a 100-acre irrigation design composes of the following components;

  1. The pump – the function of the pump is to transfer water for irrigation from one point to another.
  2. Prime mover – the prime mover is the source of power for the pump. It can be electric motors, diesel/petrol engines, or an air system.
  3. Piping – to convey the irrigation water into and out of the pump system.
  4. Valves – control the flow of water into the piping network.
  5. End-use equipment – refers to the component that uses pumping power. It can be a heating system, sprinklers, drip emitters, etc.

Pump power sources

The type of power source to choose for your pump depends on the availability and accessibility of the power source. However, power sources for water pumps are electricity, diesel/ petrol, and solar power. Electricity is best used for areas with reliable electricity supply. In addition, advantages of using electricity are reduced labor costs, and the system has high efficiency.

We use diesel/ petrol-powered generators for areas with no or unreliable electricity supply. Solar-powered pumps save on energy costs. Their power depends on solar radiation, and the initial cost of installing the system is high. By installing batteries, you can save the power available during the day and use it to run the pump when the solar radiation is low or at night.

The pump

The function of the pump in a 100-acre irrigation design is to push water through the system. It is essential to know the different components of a pump. This knowledge is advantageous when it comes to replacing worn-out or damaged parts. The members of a pump are;

  1. Casing – the casing is the outer shell of the pump. Its principal function is to protect the inner components from external conditions. The material used to make the housing should be firm and resistant to harsh external conditions.
  2. Impeller – consists of a rotating disc connected to a shaft with a set of vanes. The disc rotates, creating the energy required to induce flow in the system
  3. Motor – this component is the power source of the pump. It can be alternating current (AC) or direct current (DC) powered, fuel, hydraulic, solar, or steam powered.
  4. Shaft – the shaft connects the impeller to the motor. It transmits the power to the impeller creating the necessary force to induce flow.
  5. Volute – it is the inner casing that contains the impeller. It collects and discharges the irrigation water.
  6. Bearing assemble – offer mechanical support allowing continuous impeller rotation.
  7. Hub – the hub forms a connecting part for the engine.
  8. Seal – the seal protects the bearing assembly from the irrigation water.

Types of pumps

There are various types of pumps available in the market. The choice of type of pump depends on the use, power source, and the power of the pump. For a 100-acre irrigation design, you will need to use a powerful pump to achieve the necessary flow rates. Types of pumps available in the market include;

  1. Floating pumps – they are submersible or turbine pumps attached to a float. The pump hangs beneath the float, and the pump delivers water through a pipe connecting to it.
  2. Booster pumps – manufacturers build these pumps primarily for improving water pressure in the system.
  3. Turbine pumps – consists of a centrifugal pump mounted underwater and connected to a motor on the surface. These pumps are excellent and efficient for use in large schemes.
  4. Submersible pumps – submersible pumps are placed at the bottom of the water source. Unlike turbine pumps, the pump and motor are part of a single unit.
  5. End suction centrifugal pumps – they are widespread in the market. Manufacturers mount the pump at the end of a motor and it requires priming before the first use. The pump has an advantage in portability since it is easy to carry.
  6. Centrifugal pumps – these pumps use an impeller to create the necessary force to push the water up the system. They need priming before the first use.
  7. Displacement pumps move water through displacement. Examples of these pumps are rotary and piston pumps.

Factors to consider when selecting a pump for a 100-acre irrigation design.

The wrong choice of a pump in a 100-acre irrigation design can have profound financial implications. Purchase of a low-performance pump will mean the water supply to the plants won’t be enough resulting in yield losses. A high-performance pump will mean more pumping costs. The factors to consider before purchasing a pump for irrigation are;

  1. The pump discharge – discharge refers to the amount of water the pump supplies.
  2. The pressure – refers to the internal energy of water due to pressure on the pipe walls.
  3. Suction head – it refers to the distance a pump can suck water from a water source.
  4. Friction head – friction head is the loss in water pressure resulting from friction between the flowing water and the pipe walls. Irrigation pipes’ length, diameter, surface smoothness, and material affect the friction head in an irrigation system.

Estimated flow rate across a 100-acre irrigation scheme

To estimate the flow rate across a 100-acre irrigation design, we firstly determine the crop water requirements. Precisely, the crop water requirements vary depending on the species, growth stage, and environmental conditions. Crops grown in hot areas will need more water than those in cool regions. Water demand is usually expressed in terms of depth. To get the total volume of water required per day we multiply the total area by the crop water demand. Assuming the crop water demand is 6mm/ day, the volume of water plants need in a day is.

Volume of water plants need in a day (100-acre) =  × 400,000 m2

                                                                                                          = 2400 m3/ day

Assuming 20 hours of irrigation in a day, then the daily volume of water we need is;

Flow rate per hour =  = 120 m3/hour.

Using drip irrigation in this area with a flow rate of 2 liters per hour and spacing of 0.2 m by 0.6 m on the laterals, we can obtain the application rate.

Water application rate =

You can get the application time by dividing the crop water demand by the application rate, i.e.,

Application time =  = 0.375 hrs/ 22.5 minutes

If the field is irrigated as one whole field, then the discharge we need will be;

Estimated flow for the whole field=  = 6400 m3/ hr

To get the number of shifts that you can use, you divide the crop water requirements with the application time.

Number of shifts =  = 16 shifts

If we divide the plot into 16 plots, each irrigated in one shift, then the area and discharge of each shift are;

Area per shift =  = 6.25 acres

Discharge per shift = 6.25 × 4,000 m2 ×  = 150 m3.

To get the flow rate per shift, we divide the discharge per shift by the application time.

Estimated Flow per shift =  400 m3/ hr

Estimated irrigation hours for a 100-acre irrigation design

To get the actual irrigation hours you will need for a 100-acre irrigation design using the above requirements, we use the number of shifts and application time.

Estimated irrigation hours = the number of shifts × application time.

= 16 shifts × 0.375 hrs

= 6 hours

Use of automation for cost efficiency

We automate irrigation systems to ensure efficient water and nutrient supply to the plants. The system carries out irrigation operations with no or minimal human intervention. Automatic systems use sensors, timers, or computers to control the water and nutrient flow in the system. The system uses sensors to determine the right time to apply fertilizer and water to the plants. The sensors send the information to the computer, which decides when to irrigate depending on the data. Irrigation timers are the brain of an automatic irrigation system. Timers can be mechanical, electronic, or hybrid.

Automatic irrigation systems reduce the labor cost on a farm. The computer decides when to irrigate and supply nutrients depending on the data collected. This reduces the labor needed to operate the farm. The system releases water to the plants in the right quantities reducing water wastage. Efficient water use means less water pumping. This helps reduce the pumping costs. The system also controls the fertilizer application, reducing wastage and saving on costs.

The incorporation of a pest detection system helps detect the presence of pests early on. Control of the pests early on is much easier and cost-effective. An automatic system helps increase the quantity and quality of yield. The risk of losses is reduced significantly, ensuring farmers get returns on their investment. The use of automation in 100-acre irrigation design is necessary to help reduce production costs.

Size of filtration unit for 100-acre irrigation design

Filtration is the removal of suspended contaminants from irrigation water to avoid blocking the system. Water quality determines the filtration requirements, chemical injection, and management of the filtration system. The filtration system blocks three main groups of contaminants, i.e., biological, chemical, and physical contaminants. Biological pollutants include algae. Chemical contaminants include scale or precipitates, while physical contaminants include grit or suspended soil particles. To determine the filtration system, water emitters, and maintenance programs in a 100-acre irrigation design, you should conduct a water analysis.

The types of filters available for irrigation systems are;

  1. Media filters – media filters use sand and gravel to remove contaminants. We use them in surface water sources, especially in wastewater treatment. They are more suitable for the removal of organic compounds. Backwashing cleans the media filters.
  2. Disc filters – these filters contain a series of flexible, grooved discs stacked together. The screen size ranges from 40 to 400 mesh and is best suited for high flow rates. They are capable of cleaning physical and biological contaminants. Although when cleaning organic pollutants, they clog faster than when removing sand particles. They utilize little water when backwashing than other filters.
  3. Screen filters – they use a flexible or rigid wire woven screen to separate contaminants from water. Depending on the size of the filter, washing can either be done manually or by backwashing. We use screen filters when the amount of contaminants is little to average.
  4. Hydro-cyclone sand separators – these centrifugal filters separate water according to the difference in densities. They are helpful when separating large particles, i.e., 50 microns or larger, from irrigation water. The filter contains a sand collector at the bottom, which is easy to open and clean. Irrigation water filtration using this filter can be made more efficient by combining its use with screen or disc filters.

Filtration variables in a 100-acre irrigation design.

Several variables affect the type of filtration system to use. Some of these factors are;

  1. The flow rate – the irrigation system’s water flow rate will determine the cartridge’s size and the size of the filter inlet and outlet. The pipe sizing mostly determines the size of the inlet and outlet.
  2. Differential pressure – this refers to the difference in water pressure between the inlet and outlet of the filter. We consider the housing and cartridge differential pressures for irrigation systems sensitive to pressure drops.
  3. Location – the space available for the filter will determine the size of the filter.
  4. Viscosity – this factor determines how water flows in the filter and the pressure the system needs to push the water through the filter. High viscosity means high pressures to push irrigation water through the filter. The downside to this is that the increased pressures can force some of the contaminants through the filter.
  5. Contaminants – Different filtration systems have their advantages when it comes to filtering out various contaminants. Disc filters are suitable for high volumes of water while media filters are more suitable for filtering organic contaminants.

Determination of filter size for a 100-acre irrigation scheme.

The filter for use in a 100-acre irrigation design should be able to filter out contaminants from the water without any problems. The factors to consider when selecting the size of filter to use are the inlet and outlet dimensions, the pressure rating, the type of filter, and the mesh size. The mainline pipe diameter determines the size of the filter to use. This filter already has the requirements to meet the flow from the diameter of such a pipe. The area is large; hence you will need large pipes to handle the pressures and volumes of water. We recommend the use of disc filters when the discharge is high.

Automatic fertigation system

Fertigation is the injection of fertilizers, amendments, or other water-soluble products into an irrigation system. Automatic fertigation systems deliver just the right amounts of water and fertilizer at the root zone of the crops. The system uses sensors in the soil to detect soil moisture levels and substrate quantities. When the substrate quantity in the ground is low, a signal is sent to the computer, which supplies current to the solenoid valveMoreover, the solenoid valve enables the mixing of dissolved fertilizer with the irrigation water. Since solenoid valves are fast, the efficiency of the automatic fertigation system is high. The solenoid valves to use in this system are three-way solenoid valves.

The advantages of using automatic fertigation systems in 100-acre irrigation design are;

  1. High yields – use of sensors and timers ensures the plants get the required quantities of water and fertilizer, increasing the yields.
  2. The system is convenient – the farmer must not be present to activate the system. It is done automatically, and monitoring the system through the phone or computer is possible.
  3. Smart irrigation timers and sensors enable some systems to vary the amount of fertilizer application throughout the growing period depending on the demand.
  4. Optimization of fertilizer application – sensors monitor the substrate quantity in soil and alert the computer when the level goes low. The computer then allows fertilizer application.
  5. Cost -saving on production – an efficient fertilizer supply reduces wastage, reducing the amount of fertilizer you use.
  6. Reduced nutrient leaching – the system only supplies the required quantities of fertilizer to the plants. This reduces the leaching of nutrients into the soil.
  7. Automated fertigation systems provide the farmer with the fertilizer use data enabling the farmer to make well-informed decisions concerning fertilizer application.

Soil health in relation to the automatic application of fertilizer

Continuous planting and harvesting of crops gradually decrease the nutrients available in the soil. To ensure continuous high yields, farmers use either fertilizers or natural decomposition to replenish the soil nutrients. Fertilizer application is a preferred way of replenishing nutrients since it is fast-acting and a farmer can add specific nutrients depending on the deficit. Fertilizers help ensure adequate food supply in the world. However, overuse of chemical fertilizers has serious consequences on soil, animals, plants, and human health. The increasing population poses a threat to food security; hence the need to improve agricultural production. One way of doing this is by using automatic fertigation systems. Not only does it ensure plants get adequate nutrients, but it also protects the environment from the harmful effects of fertilizer overuse.

 Some of the harmful effects prevented by the use of automatic fertigation systems are;

  1. Increased soil acidity – an increase in soil acidity reduces the crop intake of phosphate, raises the concentration of harmful ions, and inhibits crop growth.
  2. Humus content reduction – a loss in humus content reduces the ability of the soil to store nutrients.
  3. Over-application of nitrogen fertilizers for long periods kills the balance between the three macro-nutrients. These nutrients are nitrogen, phosphorus, and potassium. The loss in nutrient balance will result in reduced yields.
  4. Toxic build-up of heavy metals in the soil – continuous overuse of certain fertilizers can result in tox metal build-up. These toxic metals are uranium, cadmium, and arsenic. The heavy metals pollute the soil and they can accumulate in the fruits, grains, and vegetables. When we consume these products, serious health issues can arise.
  5. Pollution of water sources – overuse of fertilizers will result in washing away of excess fertilizer by leaching or runoff. The water will direct the fertilizer to underground water sources or surface water sources. Fertilizer presence in water sources results in excessive growth of algae which use up oxygen in the water when they respire and decompose. An increase in the number of algae reduces the oxygen available in the water leading to the deaths of fish.

The use of automatic fertigation helps prevent all the problems mentioned above. Lastly, this system ensures plants get fertilizer in the right quantities and time avoiding overuse. It helps ensure proper soil health conditions while increasing the yields.

The pressure rating on mainline and subsequent laterals in a 100-acre irrigation design.

Irrigation pipes deliver water through the entire irrigation system. They make up a large portion of an irrigation system, making their selection very crucial to the operation of the scheme. In a 100-acre irrigation design, the pipes should be able to withstand the maximum operating pressures and convey water without excessive pressure loss or gain. You should ensure proper connection at pipe joints to avoid pressure loss through leakages. The selection of mainline pipes is dependent on economics, friction loss, and flushing concerns. During flushing, the piping network should be able to withstand the flushing velocities. Flushing velocities are usually about 0.3 m/second.

The prices of pipes available at Eunidrip irrigation systems are;

Irrigation pipe prices
Pipe diameterCost per meter
16mmKES. 27
25 mmKES. 45
32 mmKES. 70
40 mmKES. 90

Pressure rating recommendations on laterals.

The pressure at the laterals will differ depending on the irrigation method. Drip irrigation and subsurface irrigation usually have low water pressures at the laterals. Sprinkler irrigation and center pivot irrigation experience high water pressures at the laterals.

The recommended size of lateral pipes for drip irrigation
Length of lateralsLateral flow rate
 2 L/hr4 L/hr8 L/hr
40 m -50 m12 mm12mm12 mm
40 m -70 m12mm12 mm16 mm
60 m -80 m12 mm12 mm16 mm
80 m -120 m12 mm16 mm20 mm
90 m – 120 m12 mm16 mm20 mm

Irrigation methods applicable in a 100-acre irrigation design

Irrigation is the artificial application of controlled amounts of water to assist in crop production or grow landscape plants. It is one of the methods preferred nowadays to increase food production. The advantages that arise from using irrigation in crop production are;

  • Increased quality and quantity of yields.
  • Soil erosion prevention.
  • Improved crop health.
  • Optimization of fertilizer usage.
  • Inhibits weeds growth.
  • Eliminates water deficiency.
  • Acts as a shield against famine.

There are various irrigation methods available that are applicable in a 100-acre irrigation design. The major irrigation methods available are; surface, sub-surface, drip, sprinkler, and center pivot irrigation. At Eunidrip Irrigation Systems, we supply and install all irrigation types available. We have qualified and well-trained staff and you can be assured of high-quality work.

Surface irrigation

Surface irrigation involves the application of large volumes of water by the force of gravity over a farm. Types of surface irrigation methods you can use are basin, furrow, and border irrigation. We use surface irrigation methods in soils with poor infiltration rates, i.e., clay soils only. There is some earth movement involved when building bunds or trenches to control the water flow in the areas. Water flows into the irrigation area and is controlled by the use of gates or pipes. The use of surface irrigation methods is mostly applicable where there are large volumes of water and the available soils are clayey. The methods are relatively cheap to install, but they do not conserve water and a lot of it is lost to the atmosphere.

Sub-surface irrigation

Sub-surface irrigation is a method that delivers water directly into the soil layers. It can be either natural or artificial. People cannot control natural sub-surface irrigation since it involves water seeping from underground water, lakes, streams, or rivers into the soil. It is a cheap method but it is not possible to control the amount of water supplied to the plants. Artificial sub-surface irrigation involves the supply of water to the plant root zone by the use of pipes underneath the soil. The main advantage of this system is that you eliminate water losses through evaporation. We normally use this method in areas with hot climates or areas where there are inadequate amounts of water. Problems encountered when using this method are possible leakages in the pipes due to rodents or heavy machinery. This method is feasible in a 100-acre irrigation design since it conserves moisture reducing water pumping costs.

Drip irrigation

This method is the best for irrigation in terms of water conservation. We can apply it in a 100-acre irrigation design depending on the crops. Drip irrigation involves the supply of controlled amounts of water at the root zone of the plant. Emitters deliver the water to the plants at an average rate of two liters per hour. The emitters are sensitive to blockages; hence you will need to filter the water before entering it into the piping system. When it comes to designing the 100-acre farm, the layout of the pipes depends on the topography and shape of the farm. The basic rules are, that you should place the mainline along the slope and laterals across the slope. The use of this method has many advantages such as increased yields, controlled weed growth, reduced soil erosion, reduced labor costs, efficient use of fertilizers, and control of pests and diseases.

The initial costs of installing this system are high, however, the savings done on production costs afterward are worth it. At Eunidrip Irrigation Systems, our installation cost of drip irrigation per acre varies depending on the number of driplines per bed.

Drip irrigation cost per acre
Number of driplines per bedCost
2KES. 165,000
3KES. 180,000

Sprinkler irrigation

Sprinkler irrigation makes use of sprinkler nozzles to distribute water in the form of artificial rain. The sprinklers can apply a uniform amount of water over a large area depending on the type of sprinkler. When using this system, earth movement is not necessary. You should use a filter to remove contaminants that can block the sprinkler nozzles. The choice of this method in a 100-acre irrigation design depends on the crops grown, the weather conditions dominant in the region, the type of soil, and available funds. precisely, You cannot use sprinkler irrigation to grow water-sensitive plants like beans and tomatoes. This is because these plants tend to get sick when exposed to too much water on their leaves. The climatic conditions of an area affect the efficiency of water application using sprinklers. In windy areas, there is a non-uniform application of water on the farm.

Sprinkler irrigation

Sprinkler irrigation is most suitable for areas with sandy soils. This is because the water will infiltrate more quickly reducing the amount of water lost through evaporation. Sprinklers need pumps to achieve the high pressures necessary to distribute water. The introduction of pumps means increased production costs in irrigation. Despite the pumping costs, this method is very efficient depending on the usage. Its use can assure you of high returns. However, to ensure the long life of sprinkler irrigation, you should follow the necessary maintenance practices. At Eunidrip irrigation systems, we can help you know where to use sprinkler irrigation, and supply and install the whole system at affordable prices. The cost of installing a sprinkler irrigation system on a one-acre farm starts from KES. 150,000.

 

center pivot irrigation systems

Center pivot irrigation

Center pivot irrigation uses sprinklers or a series of sprinklers that rotate about a pivot. These systems are fully automated and the system covers a large area. Water application varies along the length of the pipeline with more water being applied at the end of the pipeline than near the pivot. Some more advanced systems use GIS and GPS to map out the area and distribute water according to the demand in each area. The use of this irrigation system demands large vast areas making it suitable for use in a 100-acre irrigation design.

Crops that you can grow using this method are sugarcane, orchards, maize, potatoes, small grains, alfalfa, and vegetable crops. The major factor that affects the choice of this system is the cost. Center pivot irrigation has a high starting and operational cost. Truly, this limits its use to commercial farmers only. Before deciding on using center pivot irrigation, you should ensure you have enough information to reduce risks. Eunidrip irrigation systems have experienced staff who can advise you on center pivot irrigation, helping you secure your investment. Pivot irrigations are large irrigation projects that require large areas starting from 100 acres. The cost of installation of center-pivot irrigation ranges from KES. 3,000,000 to KES. 10,000,000 depending on the area and equipment.

Eunidrip Irrigation systems’ role in the design, supply, and project implementation.

Eunidrip irrigation systems is amongst the leading irrigation companies in Kenya. We deal in irrigation, greenhouse design and construction, borehole drilling, shade net structure development, and plastic mulch supply. We also offer products as well as consultation services to ensure our clients get customized solutions to their needs.

In irrigation, we design, supply, and install all types of irrigation systems. We deal with various sizes of projects from a quarter an acre to 100-acre irrigation designs. We offer customer-friendly prices for all our products. Our customers can access us through our online shop or our physical store located at George Morara Road, Nakuru town. You can also contact us through our telephone lines or via WhatsApp in case of any inquiries.

Water harvesting

Water harvesting- dam liners in kenya

The increased pollution of freshwater sources has resulted in less clean water for domestic and industrial use. Water harvesting helps manage floods and supply water for daily use.  Water harvesting refers to collecting, treating, and storing rainwater or storm water. Storm water harvesting involves accumulating, treating, and storing water collected from creeks, gullies, ephemeral streams, and catchment areas from developed surfaces, e.g., roads, parks, and playgrounds.  Rainwater harvesting involves the collection and storage of precipitation from roofs.

Components of a water harvesting system.

We make use of the following components to collect rainwater effectively.

  1. The catchment area – it is used to collect rainwater. It can either be natural, e.g., gulleys, creaks, and streams, or artificial, e.g., rooftops.
  2. Conveyance system – transports the collected water from the catchment zones to the recharge zones. We use gutters and drains for rainwater collection.
  3. Flush system – flushes out the first spell of rainfall collected. The first spell of water collected contains a lot of contaminants.
  4. Filter – for filtering the collected rainwater removing pollutants.
  5. Tanks and recharge stations – the primary purpose of recharge stations is to store collected rainwater.

Factors affecting the amount of water harvested.

The amount of rainwater and storm water harvested varies greatly depending on the following factors.

  1. The quantity of runoff within a catchment. The greater the runoff, the more the water harvested.
  2. Availability of technology – improved technology ensures we can easily collect more water.
  3. The capacity of the storage tanks – large tanks enable more water-saving than small tanks.
  4. Impact of the environment – areas with a hot climate will evaporate some of the water.
  5. Type of roof, slope, and materials – the type of roof and slope determine the amount of water collected. The material used determines the quality of water collected.
  6. Frequency, quantity, and quality of rainfall
  7. Speed and ease of infiltration through the subsoil – fast infiltration rates mean less runoff hence less water collected. Clay soils are more favorable for collecting runoff than sandy soils.

Types of water harvesting systems

Water harvesting systems come in designs varying from simple to complex structures. The types of rainwater harvesting methods available are;

Water butt

Water butt harvesting systems collect water from natural rainfall or drain pipes. Collected Water is mainly used for watering the plants.

Indirect pumped

This water harvesting system does not rely on gravity to supply water to the outlets. The owner pumps the water collected to the tanks. The use of pumps means you can place the tank at any height. Tank placement at any height enables great flexibility to adjust the flow and pressure of water according to the requirements of a building.

Directly pumped

Directly pumped uses pumps to supply the water collected to the building. The systems can use submersible or suction pumps. Water backup from the main supply must be directed to the underground tank first before being pumped for use. We install the submersible pump in the underground tank, whereas the suction pump is placed within the control unit of the house. Using suction pumps means we don’t need to be direct water from the main supply to the underground tank. The suction pump can deal with the backup and water from the underground tank. Submersible tanks are much more efficient than suction pumps.

Indirect gravity

These water harvesting systems supply water to the outlets by gravity alone. Water collected is first pumped to the header tank, usually located at a high point. Water then flows by gravity to the outlets. The pump only works to deliver the water to the header tank.

Gravity only

These water harvesting systems use gravity only to deliver the water. The tank needs to be located below the gutter system and above the outlets. This system is energy efficient since there is no usage of pumps. It saves on costs.

Retention ponds

We usually use retention ponds to collect runoff. These ponds improve water quality through natural processes .g., sedimentation, solar disinfection, decomposition, and soil filtration. We use concrete and mud to make the base of the retention tanks, and the water is used for watering the livestock, groundwater recharge, irrigation, etc.

In-ground storage

In-ground storage systems make use of underground tanks. Their use is widespread in areas that receive rainfall in a single season. The tanks are insulated, reducing the rate of evaporation, and the water doesn’t freeze if placed below the frost line. These systems make use of electric pumps to deliver water to the outlets.

Techniques of water harvesting

We use the following techniques in water harvesting methods, i.e., rain barrels, dry systems, wet systems, and green roofs.

Rain barrels

This method is common in many households. It is easy and affordable to install, and the tanks can store significant amounts of water. The water tank is placed below the downspout of the gutter systems. The conveyance system directs the water to the water tank. Water collected can be used for domestic use or in drip irrigation systems.

Dry systems

Dry systems are similar to rain barrel systems, only larger tanks are needed, and the gutters divert water to the large tanks. The use of this technique is quick and cheap to implement.

Wet systems

In these water harvesting systems, you place the tank and collection pipes underground. The collection pipes are connected to the downspout of the gutter system and directed to the underground tanks. The tubes need proper maintenance to reduce the chances of leakage.

Green roof

Green roof techniques don’t need storage tanks. The water collected is directed to gardens or farms directly. This technique involves installing drainage systems from the roof to the garden. The maintenance costs of this method are low.

Design criteria for rainwater harvesting

Proper water harvesting designs ensure that the collected water is enough to cater to the required needs. Factors to consider when designing a rainwater harvesting system are;

  1. The use of the harvested water – the intended use of the harvested water affects the design of the harvesting system. If you want harvested water for indoor and outdoor use, then more precision is used to maximize on the available rainfall.
  2. Reliability of the system – you will need a reliable method if the water demand is high and the supply is low. Reliable systems maximize the available rainfall collecting as much as possible.
  3. Size of catchment area needed – the roof size determines how much water will be collected.
  4. Location of the catchment area relative to the intended use
  5. Required size and type of storage – the volume of water to be stored should exceed the demand.

Determination of water demand.

To determine the storage size and the system to collect rainwater, you should compute the total water demand. If you use rainwater for indoor use, it is easy to calculate the average volume of water used within the house. You can calculate water for irrigation from the plants’ water demand. Plant water demand varies greatly depending on the growing stage, the type of plants, and the soil type of an area. You may need the help of agronomists to help you determine the exact quantities required.

Determination of how much water can be captured

The amount of water to be captured is determined by the size of the catchment area and rainfall received. Not all water collected during storms is conveyed to the storage tanks. Water losses occur through evaporation, splash outs, loss during the first flush, overshoots from gutters in heavy rains, and leaks. The roughness of the collecting surface also affects the quantity of water collected. Roofs with rough surfaces trap rain in their pores, and the water is lost through evaporation. Water harvesting efficiency is also limited by the inability to collect all the water during heavy rainfall. The system loses water as an overflow when the storage tanks are full. For these reasons, we usually use 75% to 90% efficiency when computing the volume of water collected.

When computing the total water capturing surface, we consider the total area of the roof surface. We take into account areas supplied with guttering systems. Also, we use these surfaces because only these areas can collect the water for use. We take the total roof surface regardless of the slope.  To compute the total monthly volume of water collected by a roof, we multiply the monthly average rainfall received in the area by the entire roof surface area.

The total volume of water collected per month = Total roof surface area × average monthly    rainfall received × Efficiency of water collection (ranges from 75% to 90%)

We design the catchment and storage capacity to be able to cater to the demand during the most prolonged interval period without rain.

Effect of different roof materials on the quality of water harvested.

We mostly recommend the use of metal roofs in water harvesting. Water harvested using metal roofs tend to have less fecal matter bacteria concentration than other materials. Concrete tiles and cool roofs also harvest quality water with fewer bacteria. Water harvested from green and shingle roofs tends to have high dissolved organic carbon concentrations. The high organic carbon concentrations will result in high concentrations of disinfection by-products after chlorination.

Storage tanks

Storage tanks are expensive compared to other components of a water harvesting system. The tank’s purpose determines the materials, size, and location. The tank size should be proportional to the monthly water demand, monthly rainfall, and the size of the catchment area. We place tanks either underground or above the ground depending on; the surrounding landscape, underground utilities, costs, aesthetic preferences, and the capability of the foundation soils to support the tank.

Underground tanks need the construction of maintenance holes to allow easy repair and maintenance. We place above-ground tanks on flat surfaces so that the ground can withstand the tank’s weight full of water.  At Eunidrip irrigation systems, we have qualified engineers who can advise you on which concrete mixture to use to support your tank. Above-ground tanks should be opaque to prevent algae growth and degradation because of ultraviolet light. Common materials used to make tanks are plastics, concrete, wood, fiberglass, and galvanized metal. Each material has its advantage over the others.

First-flush diverters and inlet protection

The level of cleanliness of water harvesting depends on the water use. Water for drinking will need to be cleaner than water for washing. Screen filters are usually fitted at gutter inlets to remove large particles like sticks and leaves. First-flush is the first part of rooftop runoff that contains a high concentration of contaminants. The first flush is diverted away from the tank using first-flush diverters. The diverter prevents water from flowing into the tank until its chamber is full. The first-flush diverter should divert 10 liters per 24 meters square of the catchment area.

We use gutter screens and roof-washers together with the first flush diverters to prevent mosquito breeding and sediment build-up in the tank. Roof-washers use large screens that remove large debris, and we place them between the first flush diverter and the tank. We use calming inlets to minimize bottom sediment disturbance where the water enters the tank.

Conveyance system

Gutters, downspouts, and pipes make up the conveyance system.  It is recommended the gutter system should be able to carry the runoff of the 100-year/1-hour rain event. PVC, seamless aluminum, and galvanized steel are materials used to make the gutter and pipe systems. Guidelines to follow when designing the gutter system during water harvesting are;

  1. The slope of the gutters should be about 0.5%
  2. It would be best if you use expansion joints 18 meters or longer
  3. Limit horizontal conveyance pipe bends to 450.
  4. Place gutter hangers 0.9 meters in the center.
  5. One downspout per 15 meters of the gutter length
  6. Cleanouts on horizontal conveyance pipes every 30 meters.
  7. Slope of 2% of horizontal conveyance pipes

Overflow pipe

The overflow pipe directs water from a full tank while preventing soil erosion in the region. The pipe is installed at the top part of the tank and designed to handle the same flow as the gutter system for effective functioning. You can direct the excess water to gardens or nearby water sources.

Outlet pipe and distribution system

We recommend installing the outlet pipe at least 15 centimeters from the bottom of the tank. The outlet pipe draws water from the tank to the distribution system. You may need a pump to provide enough pressure to deliver the water. You can use solar pumps, diesel/petrol pumps, or electric pumps.

Maintenance of water harvesting systems

  1. Removal of the first flush after every storm.
  2. Inspection and repair of screens
  3. Remove debris from the roof, gutter screens, roof-washers, leaf guard, and first-flush diverter after water harvesting.
  4. Storage tank draining once per year to remove sediments
  5. Servicing of the pumps
  6. Emptying the rain barrel during winter to prevent freezing
  7. Cleaning out the tank using a bleach solution and then rinsing it afterward.
water-harvesting

Modern methods of water harvesting

Modern water harvesting methods have made it easier, cheaper, and more effective to harvest rainwater. Some of the modern ways of rainwater harvesting are;

  1. Rainwater overhead tanks – the tank is installed over the building or on a terrace and collects water as it flows. It is an expensive method.
  2. Ferro-cement tanks – these tanks need sand, cement, mild steel bars, galvanized iron, and wire mesh. They have a low cost, and you can make them into any desired shape. They are highly effective for use in high rainfall regions.
  3. Rainwater syringe – we use these tanks mostly in coastal regions. Rainwater collected is stored in pressure tanks and uses pipes to convey the water to depths below sea level. You can harvest the collected water using simple piston pumps during the summer season. This method helps recharge and dilute groundwater.
  4. Groundwater dam – we construct water dams in regions where the groundwater level varies. Firstly, Build a dam to distract water flow and create a reservoir. During rainstorms, water percolates into the ground adding to the pool. Also, advantages of this system are air pollutants don’t contaminate the water, and you avoid water loss by evaporation.
  5. Rainwater harvest for individual houses – involves water harvesting from a person’s roof and storing the water in tanks or wells.
  6. Rainwater harvesting for group houses – this system involves the collection of rainwater from roofs in an estate and storing the water in tanks available for everyone’s use.
  7. Raindrops – this method is cheap and helps with pollution by plastic bottles.  Furthermore, this system allows water bottles to be attached to a gutter system, helping water harvesting.
  8. Watree – a watree looks like an upside-down umbrella. The shape allows for water collection in playgrounds and parks. The watree directs the collected water to storage tanks.

Advantages of water harvesting

The advantages of water harvesting are;

  1. Decreased water demand helps preserve the already scarce freshwater.
  2. Improves quantity and quality of groundwater as in the rainwater syringe system, which helps dilute the coastal salty water.
  3. Landscape irrigation does not need a filtration system saving on costs.
  4. Easy to operate, install and maintain.
  5. Reduces stormwater runoff, flooding, soil erosion, and surface water pollution by pesticides and metals.
  6. Promotes water and energy saving.
  7. Reduces the need for imported water.
  8. Promotes water and energy conservation.

Disadvantages of water harvesting

  1. Unpredictable rainfall.
  2. Poor storage systems
  3. Regular maintenance is necessary.
  4. Requires some technical skills for installation.
  5. Limited and no rainfall can limit the supply of water.
  6. If not installed correctly, it may attract mosquitoes and other waterborne diseases.
  7. One of the significant drawbacks of the rainwater harvesting system is storage limits.

Solenoid valves for sale

Solenoid valves for sale use an electrical signal to control the flow of fluids. Precisely, We use solenoid valves to open, close, mix or distribute fluids with two or more openings. Using solenoids in fluid control is fast and effective. They require clean liquids or gases to operate at optimum levels. Application of solenoid valves includes heating systems, compressed air systems, vacuum, automated irrigation, and car washes.

Components of solenoid valves 

Solenoid valves for sale contain two major parts, i.e., the solenoid and valve body. The components of the solenoid valve are;

  1. The valve body –  Contains features that allow the solenoid to attach to the line.
  2. Coil windings –  Composed of a wire wound around a magnetic core. However, the function of the coil is to move the plunger, restricting and blocking media flow in the valve.
  3. Plunger – this is an iron-made cylindrical part that moves to open and close the valve. The plunger controls the movement of media in the valve.
  4. Inlet valve – opening that allows media flow into the valve. Solenoid valves can have one or more inlets.
  5. Outlet valve – refers to an opening that allows the media to flow out of the solenoid valve. Solenoid valves for sale can have more than one outlet.
  6. Solenoid coil – the solenoid coil is the body of the valve coil. It is hallowed, round, and made from a metal body.
  7. Solenoid spring – The function of the spring is to provide the tension needed to keep the plunger in position.
  8. Lead wires – Lead wires convey current from the power supply to the electrical valve circuit.
  9. Orifice – is located between the outlet and inlet of the valve.
  10. Sealing disc – Provides the part that shuts down the valve. The gasket should be able to resist corrosion and kept clean.
  11. Diaphragm – Diaphragms is used in pilot-operated solenoid valves because it close the central orifice from the action of pressure difference.
  12. Armature tube – It’s a hollow part that guide plunger when moving up and down. Furthermore, keep it free from dirt to reduce heat damage to the plunger.

Types of solenoid valves for sale

There are various types of solenoid valves for sale. We generally group solenoid valves according to their application, shape, and construction. In short, the types of solenoid valves under the application type are;

  • Direct-acting solenoid valves
  • Pilot operated solenoid valves

Pilot operated solenoid valves for sale.

Pilot-operated solenoid valves utilize the pressure difference between the outlet and inlet to open and close the valve. A diaphragm separates the inlet and outlet. The diaphragm has a hole that permits fluid flow to the upper chamber. The inlet pressure and the spring will ensure the valve remains closed for normally closed pilot-operated solenoid valves. The plunger closes the connection between the chamber and the outlet to close the valve. After energizing the solenoid valve, the pilot orifice opens, causing a pressure drop above the membrane. As a result, the pressure drop lifts the membrane, opening the valve.

The pressure chamber above the membrane acts as an amplifier, enabling a small solenoid to control large volumes of water. The minimum operating pressure differential required in this system is about 0.5 bars.

Normally closed solenoid valves

When the coil is energized in normally closed solenoid valves, the electromagnetic force pushes the plunger upwards, resisting the spring force. This opens the valve allowing flow. The valve is closed when the coils are de-energized. The plunger falls downwards, blocking the water flow path.

Normally opened solenoid valves.

Normally opened solenoid valves for sale are opposite to normally closed solenoid valves. The magnetic force pushes the plunger downwards when the coils are energized, closing the valve. However, when we cut the current supply to open the valve, the plunger is pulled by the spring to its original position.

Bi-stable solenoid valves

A momentary power supply can switch these latching solenoid valves. The plunger can stay in position without a power supply. They use permanent magnets to achieve this rather than springs.

Role of automatic irrigation in large irrigation projects

Automatic irrigation involves using sensors and irrigation timers to control water flow in the system automatically. Automated irrigation systems use a computer to control water and nutrient supply to the plants. Sensors and timers determine the appropriate time to irrigate. Solenoid valves are fast and can effectively manage water flow in the systems. Sensors or timers determine when it is time to irrigate the farm. An irrigation timer sends an electric current to the solenoid valves to start the irrigation process. The valve is opened depending on the solenoid type, allowing water to flow into the system.

Solenoid valves for sale can mix media in the system. This quality is beneficial for controlling fertiliser application in the system. To automate the fertigation systems, we use a three-way solenoid that allows the mixing of fluids. These valves need to operate with clean water, or clogging will occur. Clogging of solenoid valves results in leakages, reduced lifetime, and unreliable operation.

The advantages of using automatic irrigation in large irrigation projects are:

  1. There is water-saving – the systems deliver water at the right time and quantities saving on water.
  2. Energy-saving – automation reduces water use, eventually reducing pumping costs.
  3. Reduced labour costs – there is automatic watering, removing the need for many employees.
  4. Increased farming efficiency– the automatic irrigation system monitors the plants’ water and nutrient needs. This results in increased yield at the end of the season.
  5. Reduced pollution – the irrigation system applies fertiliser in the right quantities avoiding leaching into underground water sources.
  6. Time-saving – there is simultaneous watering of crops, saving time.

Role of solenoid valves for sale in precision irrigation

Precision irrigation is a form of irrigation where nutrients and water are supplied to the plants at the appropriate time and quantities. The increased world population has led to the continuous depletion of the already scarce natural resources. The number of mouths to feed has increased, with the resources needed to grow the food being the same. Precision irrigation reduces the burden on resources by efficiently using the minimal resources available.

The use of solenoid valves for sale in precision irrigation methods helps control water and nutrient supply to the plants. The types of precision irrigation methods are; surface irrigation, drip irrigation, sprinkler irrigation, and subsurface irrigation.

Application of solenoid valves for sale

Solenoid valves control fluid flow in systems, making them have many domestic and industrial applications. Some of the applications of solenoid valves for sale are:

  1. Irrigation systems use solenoid valves to control the flow of nutrients and water into the pipes.
  2. Refrigeration systems use solenoid valves to reverse the flow of the refrigerant, helping in cooling or heating depending on the season.
  3. Automatic locking doors use these valves to lock the doors.
  4. Washing machines and dishwashers use these valves to control water flow.
  5. Solenoid valves help control airflow in air conditioning systems.
  6. We use a float switch together with solenoid valves to control the inflow and outflow of water in tanks.
  7. Car washes to control the flow of water and soap.
  8. Industrial equipment uses solenoid valves to control the flow of water
  9. Dental equipment utilises these valves to control the fluid’s flow, pressure, and direction.

Selection criteria for solenoid valves for sale

The type of solenoid valves for sale available to choose is vital in determining the performance of the systems. We usually use these criteria to determine the type of valve to choose.

  1. Housing material – the type of housing material is selected based on the chemical properties of the fluid, the temperature of the liquid, and environmental factors. We use brass material for valves that use neutral media. Stainless steel has good chemical, temperature, and pressure resistance. PVC material is cost-effective.
  2. Type of solenoid valves – it is essential to know whether your system needs a three-way or two-way valve.
  3. Seal material – the selection of the seal material depends on the chemical properties and temperature of the media. The choice of the seal material affects its life span and performance.
  4. Voltage – Solenoid valves can use direct current (DC) or alternating current (AC). For instance, when using AC valves, the spring can overcome the force generated for a short period of time. This problem manifests as vibrations of the armature producing a humming sound. Hence, the vibrations cause stress on the valve causing leaks over time. The manufacturers place a shading ring around the armature to counter this problem. Accumulation of dirt particles on the armature affects the performance of the shading ring. It is essential to ensure the fluid is clean. Additionally, AC solenoid valves for sale can use direct current (DC), but you must limit the voltage and current.

    Other selection criteria

  • Valve function – normally closing or normally open valves are available under this criterion. The choice valve is dependent on the operation time. If the valve closing time is longer than the opening time, we use the normally open valve. If the valve opening time is longer than the closing time, we use normally closing valves.
  • Pressure – the selected valve must be able to withstand the maximum pressures of the system.
  • Operation type – this determines whether the application will need a direct or pilot-oriented solenoid valve.
  • Temperature – the valve materials selected should be able to withstand the minimum and maximum temperatures during application. Temperature affects the viscosity and flow of the fluid.
  • Response time – refers to the time it takes the solenoid valve to switch from opening to closing or vice versa. Small direct solenoid valves  react faster than pilot-oriented solenoid valves.
  • Approvals – ensuring the valve is appropriately certified depending on the application.
  • Application degree – the valve should have adequate protection against dust and contact.

Installation of automatic irrigation systems by Eunidrip Irrigation Systems.

At Eunidrip Irrigation Systems, we have the best specialist and equipment to help you automate your irrigation. Our prices are fair, and we make sure the customers get the best services. Automation equipment needed includes irrigation timers, solenoid valves, sensors, etc.,

Common problems encountered when using solenoid valves

Some of the common issues encountered while using solenoid valves are strange sounds while the valve is in use, the valve doesn’t open, the valve closing partially, problems with the coil, and lousy installation.

Strange sounds.

This occurs when the valve is in use during opening and closing. The reasons for the sound during opening and closing can be;

  1. A small gap between the electromagnetic coil and the plunger wall.
  2. The lock-nut of the coil is loose.
  3. The pressure difference between the inlet and outlet causes a wandering sound.
  4. As water under high pressure passes through a small hole in the pipe, it produces a hammering sound.

The valve doesn’t open.

The reasons that can cause the solenoid valves not to open are;

  1. Uneven water pressures.
  2. Dirt particles in the diagram.
  3. Corrosion of the valve.
  4. Power disconnection.
  5. One or two missing components.
  6. Burns in coils.
  7. Use of low voltage.

The valve partially closes.

Partial closing of solenoid valves occurs because many reasons. Reasons that can result in partial closing of the valves are;

  1. Pressure differences between the inlet and outlet
  2. The armature tube is damaged
  3. Manual override of the system.
  4. Residual magnetism in the solenoid valve.
  5. Damaged seals
  6. Lack of specific components.

Issues with the coil

The two significant issues experienced with electromagnetic coils are coil burning and also coil staying cold when power is turned on. The causes of this problem can be;

  1. Slow coil armatures.
  2. Short circuits.
  3. High temperatures of the fluid.
  4. Low voltages.

The farmer should ensure that the power supply is compatible with the rated coil supply voltage.  Subsequently, Check for humidity in the valve and replace the coils when necessary. You should replace the armature if it is damaged or bent to avoid having coil problems.

Poor installation.

The solenoid valves usually come indicated with arrows showing the direction of flow. However, you should install the solenoid valves in the right direction to avoid reverse pressures in the valve. Of course, the presence of reverse pressure will result in improperly closing the solenoid valve. You should install the valve horizontally or at a 300  angle. Solenoid valves installed vertically suffer from reliability issues.

Advantages of solenoid valves

  1. Leakage management – Solenoid valves can completely block external leaking and control internal leaking.
  2. They have a quick response time and are lightweight – these valves are small, saving room space. They also have a fast response time.
  3. Solenoid valves are simple, cheap, and accessible – their installation and maintenance are more straightforward than other valves.
  4. They have a wide application.

Maintenance of solenoid valves for sale.

With proper care, solenoid valves can serve for a long time before needing replacement also you should carry out maintenance practices regularly on the valves.

The standard maintenance procedure are;

  1. Disconnecting the power source and also depressurizing the system.
  2. Remove the coil and inspect the valve components. The seal should not be swollen, cracked, or damaged. You should also check on the spring for damage and also ensure the orifice body is okay.
  3. You should replace the worn-out part. In addition,  Lubrication is done on the valve to reduce wear and tear. If the solenoid valve uses water as a fluid, you should clean the valve regularly to avoid mineral buildup.  The water filter should also be clean to filter out the dirt particles.
Plastic mulch for sale

Plastic mulch for sale

Plastic mulch for sale

The world’s population has vastly increased in recent years. However, this increase has led to high demand for food. Briefly, In order to cope with the increased food demand we need to improve the efficiency of agriculture. One way of doing this is by mulching. To clarify, Mulching refers to laying materials on the soil to help provide a suitable growing environment for the plants.

Types of mulch

 

There are generally two types of mulch, i.e., organic mulch and plastic mulch.

Plastic mulch for sale 

Plastic mulch for sale utilizes polythene film to shield the plants from the elements hence the use of plastic mulch helps in smothering weeds, reduces water loss, and some types contain methyl bromide, an ozone deplete, in the soil. After covering the bed with film,  farmer plants seeds into the holes, later, user should place the plastic mulch after bed preparation is complete. Bed preparation activities include weed removal, fertilizer application, etc. However, the farmer should dig trenches around the bed and bury 3 to 4 inches of the paper mulch to secure it in place. Types of plastic mulch papers are clear mulch, black mulch, silver/ black mulch, photo-selective mulch, and biodegradable mulch.

Transparent mulch 

Clear mulch makes use of plastic films with no shade. The transparent film allows light and heat into the soil and retains the heat, warming up the earth. High heat trapped in the ground favors rapid root development. The transparent plastic mulch for sale helps in water retention and soil erosion control. These plastic films allow weeds to grow since they allow light to the soil surface. 

Black mulch

Black plastic mulch absorbs and retains warmth during the day, and the heat passes to the soil at points of contact. The advantage of good soil heating is proper root development. At night, the black mulch aids in retaining soil warmth. Since the mulch paper is dark, it doesn’t allow light in, inhibiting the growth of weeds. Also, black plastic mulch helps in frost, soil erosion, and runoff protection. Black paper mulch comes in thicknesses of 0.006 mm to 0.15 mm.

Silver/black mulch

Silver/ black paper mulch composes of one silver side and another black side. When placing the mulch paper, the silver side faces outside while the dark side faces the soil. The black side prevents light from reaching the earth helping in weed control and retaining soil warmth during the night. The silver side reflects the suns’ rays to the plants, increasing the even coloring of the fruits. The shiny side reflects light repelling insects and birds and keeps the ground temperatures low during the day. These types of plastic mulch for sale are suitable for use with melons, bananas, tomatoes, peppers, and leaf vegetables. 

Metallic mulch 

These types of plastic mulch for sale are composed of polythene sheeting coated with a thin layer of aluminum. The reflective surface wards off insects and assists in keeping the soil temperature low during the day. Insects repelled using this plastic mulch include aphids, whiteflies, and leafhoppers. The mulch also attracts many beneficial insects to the plants. Plants suitable for this mulch are tomatoes, melons, peppers, cucumbers, onions, and potatoes. It is not advisable to use metallic mulch on potatoes in cool temperatures and on eggplants. 

 

plastic mulch

Photo selective plastic films

These types of mulch papers can filter out specific light radiations. They also help in moisture retention, weed control, and soil erosion control. Types of photoselective plastic mulch for sale are:

  • Green mulch – they are green in color, and they increase the intensity of green light in the soil. The green color reduces visible light, reducing the photosynthesis of weeds and inhibiting their growth. They are more robust than black mulch and are suitable for ginger, strawberries, melons, tomatoes, eggplants, and peppers. The use of green mulch on eggplants and tomatoes increases the yields. 
  • Red mulch – red mulch can reflect infrared light to the plants stimulating the rapid growth and development of the plants. Apart from that, they also help in reducing weed growth and soil moisture retention. They are suitable for use in berries.

Bio-degradable plastic mulch

These types of plastic mulch for sale are made from polymers and are designed to biodegrade into the soil for examples, biodegradable material used in making these plastic mulches are corn starch. Additionally, the use of other plastic mulch leaves plastic waste after its usage. Thus, framers are encouraged to use these types of plastic mulch to reduce pollution. The mulch decomposition rate depends on the materials used, the soil dampness, microbial activity in the soil, and the design.

Plastic mulch for sale at Eunidrip irrigation systems

Eunidrip Irrigation Systems company holds professional staff who can advise farmers on what type of plastic mulch and plants to use on their farms. For instance, our plastic mulch for sale offers an effective way to conserve soil moisture, control weed growth, and raise soil temperatures. The available sizes of black/ silver paper mulch are 23, 30, 60, and 80 microns. To emphasis, we do not recommend using transparent plastic mulch in Kenya due to the high temperatures experienced. 

Prices of plastic mulches for sale 

Plastic mulch costs
Size Price /m2
30 micronsKES 18
60 micronsKES 30
80 micronsKES 43

The choice of size of plastic mulch for sale to use depends on the farmer’s budget, the number of seasons, and the crop location. 

Drip irrigation and plastic mulch 

Drip irrigation is a precision irrigation method that helps conserve water hence, use of drip irrigation utilizes up to 95% of the water applied. specifically, the system uses drip emitters to deliver the water to the crops’ root zone, maximizing water use. The emitters are sensitive to dirt particles; hence a water filter is necessary. Advantages of using this method of irrigation are:

  • Reduced water loss – there are few water losses to the environment.
  • Controlled weed growth – water is delivered only at the root zone, limiting weeds’ growth.
  • Energy-saving – reduced water usage means reduced pumping costs. 
  • Water-saving  – this method is efficient enabling water saving
  • Efficient fertilizer use – the system only delivers nutrients to the plants. 

Finally, by combining drip irrigation and plastic mulch, a framer can significantly increase the yields on their farm. The two methods help in moisture control and weed growth.  

How to lay plastic mulch and drip lines on the farm

The process of laying down plastic mulch involves five basic operations. These are bund making, drip pipe laying, mulch paper laying, soil covering, and hole punching. To illustrate, plastic mulch for sale can be laid manually or using mulch laying machines. However, Manual laying is time-consuming and requires a lot of labor. Hence, the need of mulch laying machines like tractor-drawn which can carry out the five operations quickly. The use of mechanized plastic mulch laying saves on labor costs and time.

Working principle of mulch laying machines 

Mulch laying machines carry out the five processes simultaneously as the tractor moves. Firstly Before starting the operation, the paper tip and drip tip are placed under the press wheel and fixed at the end. Secondly, as the tractor moves, the bund-making frame makes the soil bed. Thirdly, the farmer places the drip line under the mulch paper and unwinds the two simultaneously. fourthly, after setting the paper mulch, the hoeing blades cover the edges of the paper mulch with soil securing it in place. Finally,  a punching tool makes holes in the plastic mulch paper as the tractor is moves.

 

Center pivot irrigation

center pivot irrigation systems

Center pivot irrigation consists of a single sprayer or a sprinkler pipeline supported above the ground by towers that rotate about a pivot using wheels. Water application varies across the length of the lateral. In addition, More water is applied in areas near the pivot than areas further from the pivot. The pivot irrigation achieves this using small sprinklers near the pivot and more giant sprinklers on the other end. moreover, center pivot irrigation systems are fully mechanized and automated, and they operate at either low or medium pressures.

 

 

 

Components of a center pivot irrigation

The components of center pivot irrigation are;

Irrigation pipeline

These contain water emitters that distribute water and come in diameters ranging from 140 mm to 250 mm. The choice of diameter to use depends on the length of the pipeline and system flow. Standard diameters of irrigation pipelines are 160 mm and 200 mm. The length of the pipeline ranges from 50 m to 750 m. The irrigation pipeline is composed of galvanized light steel or aluminum for strength. Usually, the irrigation pipelines are placed at a minimum height of 3 m above the ground and spread at distances of 35 m to 40 m lengthwise. Though the standard span used is 40 m.


Water emitters

Water emitters are spaced at distances of 1.5 m to 3m along the pipeline, depending on the sprinkler type and coverage. Modern center pivots irrigation uses Low Energy Precision Application (LEPA) mode. LEPA irrigation methods refer to low-pressure irrigation methods supplying uniform and small-frequent water at or near the soil surface.  These low-pressure irrigation methods in center pivots use angle mist sprayers, bubblers, and sprayers. These three are fit on hose drips hanging from the laterals. Bubblers are placed at the height of 20 cm to 45 cm, while sprayers at 1 m to 1.8 m.

We connect hose drips by gooseneck to the lateral, and the operating pressures range from  0.5 bars to 1.5 bars. The gooseneck and hose drips are connected alternately on the laterals to balance out the stresses on the line. Discharge along the pipeline varies, with more release at the end of the pipeline than near the pivot. We fit gun sprinklers at the end of the pipeline.

Central tower

This is a structure with a height ranging from 3.5 m to 4.5 m anchored to a concrete platform. It uses angular galvanized steel profiles for strength and carries equipment necessary for controlling the system. Equipment carried on the control tower are inlets for fertilizer injection, a control panel, and a collector ring.

Control panel

The control panel enables center pivot irrigation machine handling and programming. It controls the flow, pipeline movement, speed per lap, and operation times of the center pivot. The control panel uses voltmeters to indicate and control tension. A standard control panel comes with an automatic starter, hour counter, and automatic shut-offs.

Wheels

They enable the movement of the pivot mechanism in the farm

A-frame towers

These support the irrigation pipeline above the ground. A-frame towers make use of lightweight galvanized steel or aluminum.

Spare parts for center pivot irrigation

The damaged or worn-out parts in center pivot irrigation need to be replaced as soon as possible for adequate irrigation. There are various spare parts in the market for pivot irrigation. Some of the common spare parts are;

  1. Control panel – considered to be the brain of the system. It is attached to the pivot point and gives commands on time to irrigate, what quantities to use, and the speed of rotation.
  2. Span – these are long pipes between the drive units. They carry the sprinklers and are connected with the supporting structure of trusses to hold the weight between the A-towers.
  3. Tower box – they are located at each drive unit. The work of the tower box is to tell the machine how to move, the direction, and the duration.
  4. Pivot point – This is where water enters the pivot pipes and the control panel’s location.
  5. Drive unit – the drive unit refers to the part of the pivot irrigation that makes contact with the ground. It is composed of a base beam, drive train, wheels, and various structural supports.

How center pivot irrigation works

Center pivot irrigation can supply water, fertilizer, chemicals, and herbicides. This versatility helps improve the efficiency of irrigation practices by using one machine to perform several functions. Most pivot systems use generators or power from the electrical grid to run the system. The power enables the safety circuit and the forward and reverse movement of the drive unit.

The pivot control panel operates the main functions of the machine. Depending on the control panel, different pivots will have various controls. for instance, when a farmer feeds a command to the control panel, electrical signals travel down the pivot to the last regular drive unit. Afterwards, the control panel directs the drive unit to move forward or backward depending on the instructions. Thirdly, the pivot moves led by the last drive unit until the switch arm connecting the last span to the second last tower is pulled to an angle, activating the next tower.  both towers move, starting tower after tower until the whole system moves. The center pivot system uses two types of sprinklers, i.e., impact sprinklers and spray heads, to supply water as it moves around. The stopping process starts with the tower furthest from the pivot and continues up to the nearest tower.

Pressure ratings of center pivot irrigation

Center pivot irrigation systems need to operate at the correct pressures. High pressures above the designed pressures result in increased operating expenses. Pressures below the design pressures result in uneven water distribution. Reasons for water pressure fluctuations in the system are;

  1. Change in groundwater level – decreased groundwater level will result in low pressures in the system.
  2. Leaks – occurrence of leaks decreases the water pressure in the pipeline
  3. Topography – a downward sloping topography will result in more water at the gun ends, whereas an uphill topography will result in more water near the pivot.

Pressure gauges are installed along the pipeline length to monitor the pressure changes and make it easier to detect issues. Pressure regulation is to control fluctuating pressures in the laterals. They use flow control nozzles and pressure regulators to maintain steady water flow out of the sprinklers.

Flow control nozzles

Flow control nozzles contain a flexible disc that acts as an orifice. When the water pressures are low in the pipeline, the disc remains flat, allowing water to flow freely. As the pressure of water increases, the disc bulges outwards, reducing the opening size. The bulging, in turn, reduces the flow of water through the orifice. Flow control nozzles don’t start controlling water up to pressures of over 35 psi, limiting their use to high-pressure systems.

Pressure regulators

They work by maintaining the present pressure in the sprinklers. In other words, when the pressures are low, the distance between the movable barrel and the fixed seat is large due to the force exerted by the spring. In such a position, the sprinkler flow rate is undisturbed. As pressure increases, the barrel is forced towards the fixed seat, reducing water flow in the sprinklers. Restriction of flow to the sprinkler stabilizes the pressure applied to them, producing a more constant flow rate than inflow control nozzles.

We base the selection of a pressure regulator to use on the design operating pressure of the system. Pressure regulators operate at arrange of 10 psi to 50 psi. When choosing the proper regulator, the operating system pressure should not exceed the regulator pressure by more than 50 psi.

Procedure to undertake when installing center pivot irrigation.

The procedure for the installation of center pivot irrigation is as follows;

  1. Land preparation – this process involves activities carried out before assembling the components. Practices done at this time are slope determination, pivot pad construction, and finding the center of the farm.
  2. Pivot point assembly – involves the assembly of the pivot point. To fasten the metals together, we make use of bolts and nuts. The technician should tighten the pivot point last.
  3. Span assembly – the operating temperatures of water should not go below 20 C, or the machinery will ice up, resulting in failures.
  4. Receiver and tower assembly – the technician should follow bolt tightening procedures to avoid structural failure.
  5. Electrical – involves connecting the control panel to the electric grid. It would be best if you properly ground the machine before applying power to the main control panel.
  6. Machine operation training.

Suitable crops for center pivot irrigation

We mainly use center pivot irrigation for crops that are grown on large farms and are not affected by water on their leaves. Plants like tomatoes are not suitable for irrigating by this method since they are sensitive to water.  Examples of crops grown using pivot irrigation are; sugarcane, orchards, maize, potatoes, small grains, alfalfa, and vegetable crops.

Eunidrip irrigation systems as a supplier of pivot irrigation systems

At Eunidrip irrigation systems, we deal with irrigation equipment, including center pivot irrigation systems. We install and supply the materials needed nationwide. Interested clients can make orders through our online shop, or if they are in Nakuru town, they can always visit our shop.

Other than Center pivot irrigation, we also deal with;

  • The entire drip system (All products used and installation)
  • Overhead irrigation (Installation and material supply)
  • Greenhouse construction
  • Solar dryer building
  • Net house and shade house construction
  • Dam lining
  • Borehole drilling

Capital costs and operational cost of center pivot irrigation.

Center pivot irrigation is fully mechanized, automatic, and done on large farms. Capital costs refer to the cost of starting up the scheme, e.g., cost of materials, construction costs, earth movement costs, etc. Operational costs refer to expenses incurred while the pivot irrigation operates, e.g., maintenance and repair costs.  Pivot irrigation has high capital and operating costs; hence, the farmer needs to monitor his/her investment money to ensure the best irrigation choice.

Estimation of annual irrigation costs.

To compute the annual ownership cost, we add the sum of depreciation cost, interest, repair cost, taxes, and insurance in a year.  The repair costs consist of the well cost and pivot costs. Center pivot irrigation uses machinery, and like every other machinery, they depreciate over time. We subtract the salvage cost from the original charges to obtain the depreciation cost. Labor costs and power costs account for the total operational costs in a year.

Large scale irrigation methods

There are four main irrigation types used worldwide, i.e., surface irrigation, sprinkler irrigation, drip/trickle irrigation, and sub-surface irrigation.

Surface irrigation

Surface irrigation involves allowing water to flow naturally by gravity over the land. In this case, there are three main types of surface irrigation methods, i.e., basin irrigation, furrow irrigation, and border irrigation. These methods of irrigation are suitable for areas with clayey soils. Basin irrigation makes use of bunds in a farm. The water floods the areas between the bunds of land. Furrow irrigation uses long trenches to contain the water from water sources. Border irrigation uses water supplied between strips of land using gates or pipes.

Advantages of surface irrigation are;

  1. There is easy management, and modern technology is not necessary
  2. It is a cost-effective method of irrigating

Disadvantages of using this system are:

  1. It requires a lot of water.
  2. A farmer cannot use these methods with high infiltration rate soils.
  3. There are no drainage outlets.
  4. Crops number limitation.

Sprinkler irrigation

This irrigation method involves releasing water to the plants in the form of artificial rain. Sprinklers operate under high pressures, hence the need for pumps. Filtered the water used  to avoid blockages of the sprinkler nozzles. A farmer must regularly maintain the sprinklers for effective water distribution. Some of the maintenance practices are;

  1. Regular checking of the washer at the bottom of the bearings
  2. Avoiding using lubricants on the sprinkler as it will cause blockages
  3. Removing dirt particles from coupling grooves

Advantages of sprinkler irrigation are;

  1. It helps in water conservation
  2. This method is cost-effective
  3. There is uniform water distribution
  4. We can use sprinkler irrigation on all terrains.

Disadvantages of sprinkler irrigation are;

  1. The system is not suitable for use in windy areas
  2. Sprinkler irrigation is not suitable for crops like tomatoes and beans.

Drip irrigation

This method of irrigation utilizes emitters to supply water to the plants. The drip emitters are sensitive to particles; hence clean water is needed. The system makes use of a filter to remove dirt particles from the irrigation water.  The emitters’ spacing is at a fixed distance, having a maximum flow of 2 liters per hour. However, the choice of dripline depends on the plants to be grown. In this case, trickle irrigation is an effective way of conserving irrigation water and is considered a precision irrigation method. Water used mainly flows to the crops using gravity.

Advantages of drip irrigation

  1. Soil erosion reduction
  2. The system has minimal operational costs
  3. There is weed control using this method.
  4. Efficient use of water and nutrients
  5. Increased crop yields
  6. Water flow by gravity reduces the energy cost.

Disadvantages of this system are:

  1. The emitters are prone to blockage by dirty water. A farmer can easily solve emitter blockage by cleaning the filters after using them for some time.
  2. The initial cost is high.
  3. Salinity problems.

Sub-surface irrigation

We can group this system into two, i.e., natural and artificial sub-surface irrigation. Artificial irrigation uses polythene pipes to deliver water directly to the plants in the soil layers. Natural sub-surface irrigation depends on water seeping from streams or lakes to the plants. In other words, the tubes used should be laid at depths of more than 40 cm. The farmer should filter the water to avoid clogging the drip lines.

Advantages of  sub-surface irrigation

  1. A farmer avoids water loss by evaporation using this system.
  2. There is a high degree of control of irrigation water.
  3. This method is applicable in windy and sunny regions.

Disadvantages of sub-surface irrigation.

  1. Heavy machinery can damage the pipes.
  2. Rodents or root hairs can damage the pipes.
  3. There is a risk of emitter clogging

Environmental impact of center pivot irrigation

The world’s population keeps increasing yearly, and the demand for more food increases. Center pivot irrigation can irrigate vast areas helping in food production worldwide. With limited land, irrigation is the best way to ensure adequate food production within the available space.

Center pivot irrigation has a significant effect on the environment. significantly, the irrigation system utilizes a lot of water draining aquifers in areas.  Pesticides and fertilizers are usually used in this system, which can result in water table pollution.

Advantages of center pivot irrigation

  1. The automated system reduce labor costs.
  2. There is the easy application of fertilizer and herbicides, saving on time and costs.
  3. Pivot irrigation is very reliable as the machine covers a large area. Likewise, advanced systems have GIS and GPS systems that determine the right amounts of water to apply in specific places.

Disadvantages of center pivot irrigation

  1. This system is not suitable for irrigating rectangular fields alone as some areas will receive insufficient water.
  2. The center pivot irrigation systems are costly to install and maintain. This issue and the required land size make the design unsuitable for small-scale farmers.
  3. Natural factors such as wind affect water distribution. In short, heat also results in water losses through evaporation, reducing irrigation efficiency.

Maintenance of center pivot irrigation

Lack of proper operation and maintenance of irrigation systems cause problems that can lead to improper water application. Results of improper water application are yield losses, disease spreading, nutrient losses due to leaching, and water runoff. For instance, to effectively maintain center pivots irrigations. Subsequently,  the following practices are essential.

  1. The farmer should ensure that the pivot operates at the required pressures for the designated sprinklers. to clarify, this enables the system to avoid damage by excess pressure.
  2. A farmer should replace the nozzles after referring to the pivot sprinklers chart. Most importantly, you should choose the right size of the nozzle to ensure the proper working conditions of the sprinklers.
  3. Ensuring that the speed of pivot and revolution time correspond with the amount of water required.
  4. Before starting the system, a farmer should check for leaks, missing sprinkler heads, and clogged or worn-out nozzles.
  5. If working with a variable rate irrigation system, you should check that the solenoid valves are operating correctly and the electronics have not sustained any damage.

In conclusion, by doing all these, center pivot irrigation systems can assure maximum yields.

Irrigation timers in Kenya.

irrigation timer

 Irrigation timers in Kenya are the brain of automatic irrigation systems. These systems enable the farmer to irrigate the plants at the right time and use the right quantities of water. Drip, sprinkler, or center pivot irrigation systems can use these controllers.

Features of irrigation timers in Kenya

The vital features of all irrigation timers are;

  1. Calendar and clock settings – these settings enable the farmer to set watering times and cycles.
  2. Manual start and operation station – the manual start enables the irrigation to be started without affecting the irrigation timer settings. The manual settings prove very useful, especially during maintenance practices.
  3. Master switch – the master switch can overturn the automatic functions.
  4. Master valve – opens and closes, allowing or preventing water flow to the irrigation system.
  5. Rain sensor – This sensor’s function is to detect rainfall and stop irrigation. It helps conserve water since no irrigation is needed when it is raining.
  6. Pump start lead – it activates the pump start relay, which turns on the pump. The pump start relay’s function is to detect signals from the controller. A controller should not be connected to the pump directly since it will be damaged.
  7. Battery backup – irrigation timers in Kenya use electricity to operate. To cater to power blackouts, a battery backup is needed. The battery will allow the controller to keep the date and times set even though no irrigation will occur until power restoration.
  8. Non-volatile memory enables the timer to keep the time and date settings even without the battery in case of power outages.
  9. Delay – this allows to fully close off valves in one zone before opening in another location.

Types of irrigation timers in Kenya

There are three main groups of Irrigation timers in Kenya. These three groups are mechanical, electronic, and hybrid timers.


 

Mechanical timers

Mechanical timers use gears, springs, dials, and motors to operate. furthermore, they depend on power input by humans to turn the spring. The timers are not prone to power shortage issues making them more suitable for remote areas. They lack many features and are cheaper than other types of irrigation timers. Also, when turning the timer, we compress a spring inside. As the spring unwinds, it turns the gears that move the dial. The timer finishes one cycle after the spring has completely unwound.

  1. ht time and quantities.

Electronic timers

 

Electronic timers make use of a digital screen. Unlike mechanical timers, these lack moving parts. They use integrated circuits for the clock, programming features, and memory. Since they use integrated circuits, they have a lot of features. The downside to these irrigation timers in Kenya is that they are dependent on electricity and are costly. Likewise, Smart electronic timers can adjust the water scheduling automatically.

Hybrid timers

These timers use the best qualities of both mechanical and electronic timers. They have an electric clock and mechanical switching. Furthermore, hybrid timers have more features than mechanical timers and are not prone to power shortage issues since they use motors, springs, and gears.

How to choose an irrigation timer in Kenya

The key questions to be asking when choosing irrigation timers in Kenya are:

  • Is it going to be mounted outside or inside?
  • What number of zones are there?
  • How many programs are needed?

Outdoors or indoor mounting

Indoor irrigation controllers are kept inside the house or in covered rooms to prevent damage from weather.  These controllers can be plugged into the house sockets since they come equipped with an external transformer. The transformer steps down the voltage from the sockets enabling efficient working operations of the controller. Outdoor controllers are weather resistant and durable. They have an internal transformer making them usable as indoor controllers by adding a three-prong plug and a power cord.

The number of zones in the irrigation farm

Irrigation zones refer to areas controlled by irrigation controllers. Most small-scale farms require about two to nine stations, while commercial farms need 32 to 48 zones. When deciding on irrigation timers in Kenya, it is best to choose one with extra stations to cater for future expansion.

Number of programs

A program in irrigation controllers refers to a set of instructions on the watering of crops on that day. Timers can have 1 – 4 programs installed, with most of them having two or more programs. The number of programs available in the controller determines the number of instructions given.

Water timer power sources

The common types of water power sources available for irrigation timers in Kenya are;

  • Electric powered water timers – these controllers do not need batteries. They are susceptible to power surges, and their placement is limited to areas near power outlets.
  • Battery-powered controllers – they can be placed anywhere on the farm, and the rate of battery replacement depends on the usage.
  • Solar power – solar-powered timers do not make use of batteries. The performance is affected by the weather.

Types of irrigation systems in Kenya

There are four major types of irrigation systems in Kenya. These are sprinkler, drip, surface, and subsurface irrigation. We can use irrigation timers in Kenya to automate these irrigation systems.

Sprinkler irrigation

Sprinkler irrigation systems distribute water to the plants in the form of artificial rainfall. It is an effective water distribution method, especially in large areas with fewer winds. Sprinklers are high-pressure equipment that needs the support of a pump to distribute the water. A farmer should not water plants with weak stems using this method because of the high water pressure. The water pressure will break the plants reducing their quality. Farmers should not irrigate plants that have leaves sensitive to water using sprinklers, e.g., tomatoes and lettuce.  We should do sprinkler maintenance consistently to avoid blockage of the sprinkler nozzles.

Farmers can use irrigation timers in Kenya in sprinkler systems to automate the watering process. The timer can control the system by controlling the main valve. When it is time to irrigate, a signal is sent to the main valve, allowing water to flow into the system. After a set irrigation time, another signal is sent to the main valve to stop the water flow.

Drip irrigation

Drip irrigation systems are precision irrigation methods that deliver water to the crop root zone. We reduce the water loss by other means by using this system. Water distributed using this system is under low pressure; hence, you don’t need pumps to deliver water to the crops. Farmers should filter out the water to avoid emitter blockage. The advantages of using drip irrigation systems are weed control, soil erosion control, reduced risk of pests and diseases, water-saving, and energy saving. The use of irrigation timers increases water application efficiency on the farm. Drip irrigation already has a water efficiency of 95%. With the addition of irrigation controllers, we can increase efficiency.

Surface irrigation

Surface irrigation involves methods that allow water to flow over the farm by gravity. These methods utilize a lot of water, and evaporation and runoff account for most of the water lost. This method works best in soils with poor infiltration rates, i.e., clay soils. Surface irrigation methods include;

  • Basin irrigation – this method involves building bunds on the farm, allowing water to flow between the bunds.
  • Furrow irrigation – in furrow irrigation, long trenches are dug and filled with water from rivers or canals
  • Border irrigation – this method of irrigation involves the supply of water between strips of land using gates or siphoning using pipes from rivers or streams. Surface irrigation methods are hard to use with irrigation timers.

Sub-surface irrigation

Sub-surface irrigation involves water supply to the crops directly to the soil layers. Also, we can categorize this method into two, i.e., artificial or natural sub-surface irrigation. Natural sub-surface irrigation involves water leaks from sources of water like underground streams. Artificial sub-surface irrigation involves the application of water beneath the soil using pipes. The depth of the pipes should be more than 40 cm to avoid damage by machinery. This method helps in water-saving by avoiding water losses through evaporation. Also, Irrigation timers in Kenya serves as automation subsurface irrigation.

Smart irrigation timers in Kenya.

Smart irrigation controllers can monitor and control water and nutrient supply to the plants. They can be categorized into two major groups, i.e., Climate-based controllers and Soil moisture sensors controllers.

Climate-based controllers

These irrigation timers in Kenya are also known as evapotranspiration controllers. They depend on evapotranspiration data to decide when to irrigate. Climate-based controllers make use of local weather reports to adjust the irrigation schedules. We can group them into three types.

  • Historic evapotranspiration controllers – these controllers use pre-programmed water use curves of different regions from historical data.
  • Signal based controllers – the timers make use of meteorological data from available public sources, and then the evapotranspiration data is computed.
  • On-site weather measurement controllers – On-site weather measurement controllers take real-time measurements and compute the evapotranspiration data continuously. The data computed is used to adjust the water supply to the farm.

Soil moisture sensors

Soil moisture sensors use sensors in the ground to decide when to irrigate. Unlike the climate-based irrigation controllers that use evapotranspiration data, soil moisture sensors use volumetric soil water content. The volumetric water content refers to the portion of the whole soil volume occupied by water. We set the controller to start irrigating when the volumetric water content reaches a certain threshold (usually 10% -40% ). The threshold chosen is dependent on the soil type and vegetation that has grown in the area.

Smart irrigation add-on sensors

We add add-on sensors to smart irrigation timers to improve the system’s efficiency. Examples of add-on sensors we use are rain, freeze, wind, soil moisture, and irrigation flow.

Rain sensors

Rain sensors interrupt the irrigation cycle when it starts to rain. This helps in saving costs and water due to unnecessary runoff.  Place Rainfall sensors in open fields to avoid interruption. There are three types of rain sensors available, i.e.,

  • Cup/ basin rain sensors. As it rains, water accumulates in the cup/ basin, and the basin’s weight interrupts the irrigation cycle. These rain sensors are prone to debris, and you should clean them regularly to avoid errors.
  • The second type of rain sensor uses two electrodes and a cup. As it rains, water accumulates in the cup.
  • Expanding discs rain sensors – these rain sensors make use of discs that expand as they absorb water. When the discs expand to a certain point, they activate a switch that interrupts the irrigation cycle. The wet discs stop the irrigation cycle until they dry up. Unlike the first two types, disc rain sensors have low maintenance and high reliability. It would help if you replaced the discs at least once per year.

Wind sensors

The wind is a significant hindrance to irrigation, especially sprinkler irrigation. It reduces the amount of water infiltrating the soil and disturbs the water application uniformity. Wind sensors help detect wind speeds and stop the irrigation cycle once the wind speed exceeds the set threshold. These sensors help improve on the efficiency of water distribution.

Soil moisture sensors

Farmers use these sensors to measure the amount of water in the soil before an irrigation cycle. The cycle, interruption occurs when there is excess water, preventing water wastage. Some of the soil moisture sensors also have soil freezing sensors. These sensors interrupt the irrigation cycle once the soil temperature falls below 00C

Freeze sensors

Freeze sensors interrupt the irrigation when the temperatures go below 0C. In addition, Shutting down irrigation water at these temperatures assists in lengthening the life of the irrigation system and avoiding the icing of paths.

Irrigation flow sensors

We use water flow sensors to detect the water conditions as it moves in the system. These devices can measure the flow rates and amount of water delivered. more ever, the irrigation flow sensors detect how fast or slow water is moving and send the data to the controller. A farmer can use this information to detect problems in the system and conserve water. If there is a leakage in the systems, the sensors will detect low water pressure and take the appropriate measures. When the water flow is high, the sensor detects it and sends the information to the controller, reducing the amount of water flowing.

Recommendations for irrigation timers in Kenya.

Irrigation controllers utilize power to operate, and the usage has cost implications. A farmer can follow these recommendations to reduce the cost of using irrigation timers in Kenya.

  1. You should schedule irrigation to happen very early in the morning. It is best to irrigate between four and nine in the morning when the winds are not strong, and the temperatures are cool. This will help reduce water loss.
  2. Adjusted Irrigation timers to give out the right amounts of water to avoid water runoff.
  3. Rain sensors are beneficial because they help avoid irrigation when it is raining, saving on costs.
  4. Wind sensors reduce water loss by the wind in sprinkler irrigation systems .
  5. Finding out your irrigation water output will help in better scheduling using the timers.

Advantages of using irrigation timers in Kenya

  1. Convenience –  Irrigation timers in Kenya   turn on automatically without human aid. This removes the human error of forgetfulness.
  2. The owner must not be present to turn on the system.
  3. Irrigation timers can supply the right quantities of water needed at the right time. Some smart controllers are even able to adjust the water output throughout the season.
  4. Low production costs. The efficient water application saves on energy and water costs.
  5. Fertilizers application- When the substrate quantities are low, the sensors can detect the change and fertilizer supplied through fertigation.
  6. Reduced nutrient leaching – the use of sensors in the soil and irrigation timers assists in ensuring an optimum supply of fertilizer to the soils. By doing so, we avoid nutrient leaching.
  7. Smart irrigation timers can collect data on the soil and plant conditions enabling the farmer to make informed decisions.
  8. Increases yields – using intelligent irrigation timers, ensures water supply and nutrient supply at the rig

Cost of one hectare green-house in Kenya

COST OF ONE-HECTARE GREENHOUSES IN KENYA

The construction of greenhouses makes it easier to control the growing environment of the crops. Moreover, high-value crops are primarily grown in greenhouses to minimize the risk of losses. In the greenhouse, it is possible to control the temperature, humidity, light penetration, pests and insects, water supply and nutrient supply. Most commercial farmers of high-value crops set up big greenhouses which can cover up to one hectare of land. The cost of one-hectare greenhouses is fairly high. Hence, a lot of care and precision must go into construction.


Cost of different sizes of greenhouses

Greenhouses come in various sizes and materials. The construction costs mainly determine the type of greenhouse to choose. We can group greenhouses into two according to the materials used for the frame. These two groups are wooden and metallic greenhouses. Wooden greenhouses need to be treated first before use to avoid damage by termites or rotting. Nails and barbed wire hold the greenhouse polythene in place in wooden greenhouses. We can’t use a wooden framework in large greenhouses due to the weight of the structure. This means that the farmer cannot evade the cost of one-hectare greenhouses by going for cheaper materials. Metallic greenhouses use of galvanised steel, iron or aluminum to support the structure. Galvanised steel and aluminum have the advantage of rust resistance, and tapping screws, profiles, and wires hold the greenhouse polythene in place. At Eunidrip irrigation systems, we have professionals skilled at building quality wooden and metallic greenhouses. The costs of greenhouses we offer cater for the; structure, materials, drip irrigation system and installation labour. The charges for building different sizes of greenhouses are displayed below.

Greenhouse construction costs
SizeMetallic greenhouses 
8 m × 15 mKES 200,000
8 m × 20 mKES 235,000
8 m × 24 mKES 255,000
8 m × 30 mKES 300,000
8 m × 40 mKES 480,000
8 m × 48 mKES 500,000
16 m × 24 mKES 500,000
16 m × 30 mKES 550,000
16 m × 40 mKES 890,000

Wooden greenhouses are generally cheaper than metallic greenhouses because of the high cost of galvanised steel, iron and aluminum. However, metallic greenhouses have a much longer life span. 

Greenhouse dimensions

Greenhouses come in all shapes and sizes. The main factors determining the size of the greenhouse to be chosen are the available land and the construction cost. We can group greenhouses in Kenya into three classes depending on the size. These three classes are;

Greenhouse dimensions
Small greenhousesMedium greenhousesLarge greenhouses 
  • 4 m x 5 m
8 m × 48 m>16 m × 40 m.
6 m x 10 m16 m × 30 m 
6 m x 12 m16 m × 40 m 
6 m x 15 m  
8 m x 15 m  
8 m x 25 m  
8 m x 30 m,  
8 m x 45 m  
8 m x 48 m  

Cost of automated greenhouses Automated greenhouses are those whose internal environment can be controlled by a computer. The computer uses sensors to determine the correct times to irrigate or start and close the air conditioning system. The system also enables remote monitoring of the greenhouse. Automation of large commercial greenhouses is costly. The average cost of a fully automated greenhouse ranges from KES 3030 to KES 5303 per m2. This means that the average cost of a one-hectare greenhouse, which is fully automatic, will cost 30 million to 53 million Kenya shillings. Greenhouse owners choose to automate the greenhouses or partially automate them fully. Factors that affect the cost of automated greenhouses are:

  1. Required area- the larger the required area, the more construction cost.
  2. Construction materials – The type of chosen materials affect the lifespan and maintenance costs. Durable materials are more costly than poor quality materials, but they will save on maintenance and repair costs.
  3. Framing – the chosen material should be strong enough to support the whole structure. Large one-hectare greenhouses can only use metals as the framing materials. Galvanised steel, iron and aluminum costs much more than wood or PVC plastic pipes. 
  4. Environmental control 

Cost of one-hectare greenhouse environment control

As we have seen, setting up a fully automated greenhouse is very costly. Many farmers choose to automate only parts of the greenhouse. A Heating, ventilation and Air Conditioning (HVAC) system is a fully automated system that controls heating and air circulation in the greenhouse. It can come as one unit or separated units. The HVAC system can cost up to KES. 574,000 or more depending on the features of the system. The usage of this system increases the overall cost of one-hectare greenhouses. Alternatives to using this are system boilers and small Horizontal Airflow (HAF) fans. The boilers assist in heating the greenhouse, and the operating cost depends on the fuel costs. HAF fans assist in the ventilation of the greenhouse, and the price ranges from KES 11,000 to KES 18,000.

Glowing lights come in various sizes and prices depending on the wattage and power generated. The average cost of lights ranges from KES 2,300 to KES 14,000. Thermostats and sensors are used to monitor the internal environment of the greenhouse. They can be used together with the heating and cooling systems to control the air temperature of the greenhouse automatically. The cost of thermostats varies depending on the features. The price ranges from KES 68,000 to KES 170,000. 

Importance of automation on big greenhouses 

Automation of one-hectare greenhouses has helped commercial farmers be more confident in their practices. Here are some of the importance of automated greenhouses. 

  1. Creation and maintenance of an ideal climate – these greenhouses use sensors to detect changes and correct them in the greenhouse. The parameters managed by the computerised system are; heat, humidity, light levels, ventilation, soil nutrient levels, pests and soil moisture levels.  
  2. Reduction of energy costs – automated systems monitor the soil water levels. When the levels are below the required amounts, the system turns on the irrigation and supplies only the required quantity. This saves on water and energy use in the greenhouse.
  3. Remote real-time monitoring – by linking the computer to a mobile device or laptop, a farmer can monitor the conditions of the crops in the greenhouse.
  4. Reduced labour costs – the cost of one-hectare greenhouse is high. By using automated systems, a farmer can cut down on labour costs. 
  5. Analysis of plants’ growing data – Data collected with the computer are; the plant cycles, soil data, nutrient intake data and climate control report. This information will help the farmer know the best growing conditions and how to achieve that. 
  6. Improved plant health and quality – sensors inside the greenhouse help detect pests and diseases early on. The farmer can control the disease by ensuring high quality and quantity yields.

Project management during greenhouse construction 

Project management involves starting up, planning, executing and closing a task, meeting the client’s demands at the right time. The steps involved in greenhouse construction project management are:

  • Designing and feasibility studies
  • Solution planning and detailed designing 
  • Building and execution 
  • Training and after-sale report

Designing and feasibility studies 

This is the first step in any greenhouse construction project. At this stage, the client comes to us to build a greenhouse. The steps involved in this stage are; 

  1. Greenhouse feasibility study – this is done to check whether the location of the greenhouse will be suitable.
  2. Crop and climate assessment – climate and crop assessment will determine the design of the greenhouse.  
  3. Financial requirements planning – done to determine the overall costs of the project  
  4. Initial greenhouse technical design. The factors to be considered during the designing phase are:
  • The climate of the area – the area climate determines the type of equipment to be prioritised in the greenhouse.
  • Greenhouse size to be constructed – whether is for a small scale farmer or commercial farmer 
  • Crops grown in the greenhouse
  • Greenhouse materials availability
  • The topography of the land
  • Government policies 
  • Maximum light transmission required
  • The expected lifetime of the greenhouse 

Detailed design and solution planning

This stage comes next after the client has paid the full cost of a one-hectare greenhouse. This stage involves engineering works and planning, designing the structure, heating and cooling system design, irrigation control, and greenhouse construction schedule.

Execution and building 

The execution phase involves the construction of the greenhouse on the site. It should be done according to the schedule to be completed at the right time. The stages involved are;

  1. Project scheduling – involves planning the work to be done on the available days.
  2. Logistics – transportation of the required materials to the site.
  3. Subcontractors management  
  4. Supervision of the whole project. 

Training and after-sales report.

This stage comes after the project is completed. The project is handed over back to the client, and training is done. If any technical or operational support is required, it is done during this stage. Training done at this stage can be how to start and stop the equipment, how to operate the systems in the greenhouse and maintenance practices. Technical support and operational support offered are repair and maintenance services etc. 

Availability of materials for greenhouse construction.

The type of greenhouse to be constructed determines the kind of materials to be used. At Eunidrip irrigation systems, we have a variety of materials that you will need for your greenhouse. These materials are reasonably priced and can be purchased through our online shop. We can deliver the materials to any place in Kenya from Nakuru. Common materials used for greenhouse construction are;

  1. Wood – used mainly in wooden greenhouses for the pillars, supports and reinforcements.
  2. Galvanised steel – these are used in metallic greenhouses as pillars, supports, reinforcements, arches, beams and straps, canals and crop wires
  3. Aluminum – aluminum is used for pillars, supports, reinforcements, arches, beams and straps, canals and crop wires.
  4. Iron – iron is used to make the support structure of the greenhouse. It is used in beams, pillars and straps.
  5. Concrete – for making foundation supports
  6. Nails – used to hold the polythene in place in wooden greenhouses
  7. Tapping screws – they make use of a drill to secure the profiles in place 
  8. Profiles and wires – these two are used together in metallic greenhouses to hold the greenhouse polythene
  9. Insect nets – usually are placed on the sides of the greenhouse to allow air inside while still protecting against insects.
  10. Covering materials – greenhouse cover materials can be plastic films, glass or rigid plastics. These materials protect the greenhouse against external factors while allowing light to pass through. Examples of plastic films are polyethylene copolímeto ethylene vinyl acetate, polyvinyl chloride plastics, and multilayer. Rigid plastics used include methyl polymethacrylate, polycarbonate and polyester

 

COST OF ONE-HECTARE GREENHOUSES

Factors to consider when setting up a Greenhouse 

Before setting up the greenhouse, there are several factors to consider. Considerations during site selection are essential. The following factors affect the location of the greenhouse site.

  1. The water and electricity supply – greenhouses use drip irrigation systems to supply water to the crops, and automated greenhouses require electricity to operate. It is crucial to ensure the greenhouse is located where these two things are to ensure an efficient system.
  2. The micro-climate conditions – micro-climate conditions refer to weather conditions that are present only in a specific location, e.g., fogging during certain times of the day. 
  3. Road network – if the greenhouses are going to be used for commercial farming, it is essential to have a good road network. A good road network will ensure the product gets to the market at the right time
  4. The orientation of the greenhouse – the greenhouse should be oriented in a direction that ensures maximum light penetration during the day
  5. Presence of trees – trees near greenhouses will form shades reducing light penetration into the greenhouse.
  6. Soil at the site – the soil should provide adequate drainage to avoid cases of water accumulation in the greenhouse.
  7. Topography – a slope of about 1% is desired so that water can drain away from the greenhouse site.
  8. Wind velocities – if the wind velocities are high, it is easy for the greenhouse to be damaged. The planting of windbreakers can assist with this problem.
  9. Labour availability – large greenhouse projects will require more labour than small projects. 

Greenhouse foundation 

A greenhouse foundation should be solid and stable enough to support the whole structure. The first step in foundation construction is deciding on the depth and width to dig. The depth to be dug depends on the soil’s bearing capacity, the depth of shrinkage and swelling for clay soils, minimum practical foundation depth, and the groundwater table. Level ground is vital in the stability of a foundation. Levelling of the floor is usually done in areas with very steep slopes. A level ground ensures;

  • Greenhouse stability during storms
  • Durability of the greenhouse materials
  • Repair and maintenance cost savings 
  • Neatness because there are no puddles of water in the greenhouse. 

The foundation of a greenhouse should meet the following requirements 

  1. Able to safely contain and distribute the weight of the greenhouse.
  2. The foundation footing should rest on undisturbed soil and at a 50 -60 cm depth.  

One hectare greenhouse construction for roses

Roses are high-value crops that are primarily grown in greenhouses to ensure maximum yield. One-hectare greenhouses for roses come in dimensions of 120 m by 80 m. They are built using galvanised steel or aluminum to provide adequate support for the whole structure. The cost of one-hectare greenhouses is above KES 23 million. The metalwork done on one of these greenhouses costs about KES 12 million.

One hectare greenhouse construction procedure 

  1. The first step in any greenhouse construction is to mark out the support points on the ground. 
  2. Foundation digging for the supports is done next.
  3. Metal painting to avoid rust 
  4. After digging, metals for support are placed in the ground, and the base is reinforced with concrete.
  5. Arch making and mounting on the greenhouses
  6. Front porch construction
  7. Insect net placement on the sides
  8. Greenhouse polythene mounting 
  9. Drip irrigation set up in the greenhouse – main lines (160 mm), submain lines (90 mm) and laterals (40 mm) are used in the drip system. 

Effects of climate on large greenhouse projects

To build large greenhouses, a farmer must clear vast areas of land. The reduction in trees in an area directly impacts the rainfall received in an area. Trees act as windbreakers resulting in rainfall formation and soil erosion control. Large greenhouses construction will increase soil erosion and dry conditions in an area. 

In most greenhouses, pesticides and fungicides are used to control pests. The pesticides and fungicides used, end up contaminating the air. This is especially true in large greenhouses, which make use of a lot of pesticides. This problem can be controlled by encouraging farmers to use natural ways to control the pests, e.g., using ladybugs to feed on the pests.  

The construction of large greenhouses will require heavy machinery. These types of machinery use fossil fuels that, when burnt, release emissions toxic to the environment. Large greenhouses projects produce many products that need vehicles to move the produce to the market. These vehicles also use up fossil fuels, releasing emissions toxic to the environment. We can solve this problem using electric cars.

Large greenhouse projects require large volumes of water. This is why most of them are located near sources of water. This can negatively impact the environment, especially during the dry seasons when the water level goes down. The fish will be affected, leading to the migration of the fish in the area. 

Returns on investment cost of one-hectare greenhouses 

As much as the cost of one-hectare greenhouses is high, the returns on the investments are worth it. Large greenhouses mean more produce can be grown in ideal conditions, maximising profits. Most of the systems in the greenhouses are automated, ensuring production efficiency. Automation helps in reducing labour costs, energy use and water use. This, in turn, saves on production costs. Kenya being a country dependent on agriculture for its economy, an ample supply of agricultural produce can assure a farmer of high returns.

Button dripper irrigation for avocados in Kenya.

Button dripper irrigation for avocados in Kenya.

 

Button dripper irrigation for avocados in Kenya.

Avocado farming for export has expanded recently in Kenya. By using button dripper irrigation for avocados in Kenya, farmers are assured of a 30% increase in the yield. A variety of avocado trees are grown in Kenya, including

  • Hass.
  • Fuerte.
  • Nabal.
  • Hayes.
  • Tonnage.
  • Ethinger.
  • Keitt.
  • Reed.
  • Puebla avocados.

Water used in Avocado trees in Kenya

 Avocados are water-sensitive plants that require the right amount of water to develop properly. When supplied with too much water, avocados tend to develop root rots, and when given too little water, there is reduced yield or even death. Root rots cause the roots to decay and die, eventually causing the whole tree to die off. 25 mm to 30 mm of water per week is recommended for the best yield on an avocado farm. However, these figures vary greatly depending on:

  1. The farm’s soil type – sandy soils will require more water for irrigation than clay or loamy soils. 
  2. Size of the trees – large trees need more water than small trees.
  3. Growth stage – flowering avocado trees will need more water than those that are not.
  4. Slope of an area – water application should be done more carefully to avoid erosion if the slope is steep.
  5. The climate of an area – area with hot climates will need more water for avocados compared to areas with cool climates.  

Many benefits arise when irrigating avocado trees; some of these benefits are:

  1. There is an increased yield
  2. The avocado trees mature faster, and fruit production is consistent
  3. There is reduced water stress on the trees 
  4. The rate of flower and fruits dropping is reduced.

Using button dripper irrigation for avocados in Kenya.

Avocado trees’ roots tend to grow more horizontally than vertically. The root ends usually are located at the edge of the canopy.  For an efficient irrigation system for avocados, the system must be able to properly distribute water at the right location and in the right amounts. There are a variety of irrigation methods used in avocado farms. These irrigation methods include button dripper irrigation systems, pressure compensated driplines, and micro-sprinklers.

Button dripper irrigation for avocados in Kenya.

The use of button dripper irrigation for avocados in Kenya has proven to be an effective way of supplying water, especially in the first year of the avocados. In the first year, the avocados do not have a widespread root system, and that ensures the effective use of button drippers. Drip tapes can not be used to supply water to avocado trees due to their low flow rates. Drip tapes have flow rates of about 2 liters per hour, whereas button drippers have flow rates of between 1 liter per hour to 60 liters per hour. 

The operating pressures of button drippers range from 15 to 25 PSI depending on the flow rate. Button drippers come in thicknesses ranging from 1mm to 1.3 mm. Thick button drippers are used in more permanent sub-surface irrigation systems, whereas 1 mm button drippers are used in temporary systems.  Button drippers come in two types; these are:

  • Adjustable button drippers – these types of button drippers come with a threaded crown that adjusts the amount of water flowing. 
  • Non-adjustable button drippers – non-adjustable button drippers lack threads hence only supply water at a fixed rate.

Button drippers make use of a swirling flow path which causes turbulent flow. The main advantage of this type of flow is reduced clogging of the button drippers.  When it comes to laying down button dripper irrigation for avocados in Kenya, the number of trees determines the number of button drippers needed. The farmer determines button dripper systems spacing, unlike drip lines with fixed emitter spacing. 

Advantages of button dripper irrigation for avocados in Kenya

The benefits of using button dripper irrigation for avocados in Kenya are:

  1. Irrigation system is applicable in all landscapes.
  2. Water distributed at the root zone reduces water losses. 
  3. High efficiency in fertilizer application due to fertigation.
  4. This system uses low energy since the water flow is by gravity.
  5. Reduce clogging of the button emitters due to turbulent flow.
  6. It reduced growth of weeds.
  7. The button drippers are resistant to ultraviolet rays, chemicals, and fertilizer. 

Pressure compensated driplines 

Pressure compensated driplines are driplines equipped with a regulating mechanism that controls the flow out of the drip emitters. This means that even if the pressure in the drip system increases, water flow does not change. It is a suitable method to ensure equal water distribution throughout the farm, ensuring equal growth. These drip lines are also useful for irrigation on steep slopes since the water flow is constant. In irrigating avocado trees in Kenya, this system is beneficial when the trees have more than one year and large canopies.

In avocados, the root tips are located at the edge of the canopy. The use of pressure compensated driplines ensures an equal supply of water to the roots zone of the avocado trees. The pressure-compensated dripline is rolled around the tree with a circumference equal to the canopy. The number of rolls depends on the plant’s water requirements, soil type, topography, and climate of the area.  By doing so, equal volumes of water are distributed to the avocado root zones.

splinkler

Micro-sprinklers serves as water and fertilizer supplier in avocados. Due to ease in repair and maintenance, laterals on the surface are more preferred than buried laterals. Micro-sprinklers apply water to the plants’ root zone, helping inefficient water use. Where sprinklers are arranged at equal distances between the avocado trees. Such that each sprinkler distributes water to one side of two trees. Micro-sprinklers distribute water at a range of 15 liters per hour to 75 liters per hour. Most farmers start with small sprinklers when the trees are young and are switched out for larger sprinklers when the trees are large. The choice of micro-sprinkler chosen depends on the desired water pattern, water flow, water pressures, and the spacing between trees. 

The types of micro-sprinklers available are:

  1. Short radius micro-sprinklers –  Come in ten sizes, with flows ranging from 26 liters per hour to 300 liters per hour.
  2. Long radius micro-sprinklers – these types of micro-sprinklers are used to irrigate trees that have extensive root volumes. They also come in ten sizes, with flows ranging from 26 liters per hour to 300 liters per hour.
  3. Jet micro-sprinklers – They come in five sizes, with flows ranging from 37 liters per hour to 113 liters per hour.
  4. Pressure compensated micro-sprinklers – these micro-sprinklers have a mechanism that helps them regulate water flow out of the nozzle. This ensures equal distribution of water to the trees.
  5. Non-pressure compensated sprinklers – these micro-sprinklers lack a pressure regulating system and can distribute water over a large diameter. They have a high-water distribution uniformity. 

Avocado farming methods and practices 

Avocados grow in various soils, be it acidic or alkaline soils. They do well in the warm region and can withstand low temperatures of up to – 60 C. Avocado farming methods and practices help ensure high yields and proper care for the avocado trees. Button dripper irrigation for avocados in Kenya has helped in most of these practices, making it more appropriate. Some of these farming methods and practices are:

Management of button dripper irrigation for avocados in Kenya

It is vital to ensure efficient management of water released to the avocado farms. Avocadoes are sensitive to the amount of water they receive; hence, there is a need to manage irrigation water.

Management practices for button dripper irrigation:-

  1. Carrying out avocado cultural management practices like pruning to avoid water wastage.
  2. Removal of weeds which tend to compete with the avocadoes for water.
  3. Application of mulch, which helps preserve soil moisture.
  4. By reducing the amount of water used when irrigating on slopes. This reduces the amount of water wasted as runoff
  5. Cutting supply of water to sick or damaged trees. This ensures there is no wastage of water by providing to unnecessary plants.
  6. By stumping canopied trees. Water loss in plants is mainly through transpiration. Transpiration is the movement of water from the roots through the trees and to the atmosphere. By stumping out canopied trees, we reduce water loss on the farm 
  7. Thinning out crowded groves. Crowded groves mean more water needed and also lost through evapotranspiration. 
  8. By keeping low skirts on avocado trees. By keeping low skirts on avocado trees, there will be ample shade provided on the root base reducing the rate of water loss by evaporation.

Salinity control using button dripper irrigation for avocados in Kenya

Avocados are  highly sensitive to salinity. High salinity hinders water absorption through the roots resulting in improper photosynthesis and root growth. Button dripper irrigation for avocados in Kenya help reduce salinity by providing enough water to leach out excess salt.

Fruit drop control in button dripper irrigation for avocados in Kenya

Fruit drop in avocados is when avocado trees drop their fruits to eliminate defective or weak seeds. As much as the plants control this process, reducing the number of fruits dropped is possible. Button dripper irrigation for avocados in Kenya helps control fruit drops. Button drippers ensure an adequate water supply to the trees, reducing water stress on the plants. This decreases fruit drops. 

Fertilizer application using button dripper irrigation for avocados in Kenya

Avocados need a constant supply of nutrients throughout their growing period. The nutrients that avocados need mostly are nitrogen, zinc, potassium, and phosphorus. These nutrients are water-soluble. Thus, delivered using irrigation system. Button drippers for irrigation for avocados in Kenya are suitable for an effective supply of water and nutrients to the trees. PH measurements obtained from the soil determines when to apply fertilizer. Another way is by carrying out nutrient analysis on the avocado leaves. 

Pruning 

Is a process of cutting dead or living branches of a tree/crop to promote growth. Followed by these principles 

For example, the avocado plant should:-

  • Not undergo over-pruning or under pruning.
  • Keep pruning tools clean.
  • Prune healthy and sick plats separately.

Pruning principles:-

  • Remove deadwood from the trees during pruning.
  • Cut cleanly and in line with the trunk contours.
  • Design a conical shape to improve on unproductive bare areas and good light interception.
  • Removed All V-type crotches.
  • Prune trees growing on slopes to a lesser height than those on flat areas. 
  • Prune horizontal branches growing low to the ground.  

Freeze protection 

Avocados tend not to do well in low temperatures; hence it is vital to carry out various practices during cold conditions to protect them. Where there are mature groves, it is best to provide either orchard heaters or wind machines to prevent frost damage. If avocado trees lose their leaves due to cold conditions, it is best to apply whitewash to those areas to prevent sunburns. A blanket placed over young trees protects the young trees against cold conditions. Additionally,  molding the soil protect Mature trees on the tree trunk.  

Grafting 

Done by connecting avocado branch onto another rootstock of a different trees. As the two grow, they fuse to form one tree. This method ensures high quantity and quality yields. And, Speed up bearing of fruits. For a high grafting success rate, the two parts should be closely related. The common grafting method used on avocadoes is the cleft grafting method. Cleft graft is used for joining scions to larger pieces of root stalks. Tools used are a knife, mallet, and sealing wax.

The first step is to drive the cleaving tool six inches deep into the rootstock using a mallet. Next, you make a long wedge about six inches at the base of the scion. Insert the scion up to the base of the wedge on the rootstock. Seal the point of union using the wax and then follow up with care.  

Market regulations around avocado export.

Kenya is amongst the top avocado producers globally, with an average of 115,000 tons of avocado produced per year. The local varieties dominate the total avocado produced in the country with a 70% share. The Hass and Fuerte varieties dominate about 10% and 20% of the quantities produced in the country. Kenya is the sixth-largest exporter of avocados to Europe, with Peru being the major competitor. About 70% of the total export is from small-scale farmers who export through intermediaries. 

Uses of avocadoes 

Avocados are rich in proteins, fats, carbohydrates, magnesium, potassium, and vitamins E, C, and K. Aside from consumption purposes, avocados have other important uses. Some of these uses are:

Manufacturing:-

  • Hair products
  • Fabric dyes
  • Face masks
  • Anti-wrinkle eye treatments
  • Making soap
  • Treating sunburns.

Dam liners for sale in Kenya

dam liner for irrigation

Dam liners for sale in Kenya

Why choose to purchase a dam liner for sale in Kenya? In the recent years there has been rapid changes in climate especially in Africa. In the past African farmers would plan when to plant and to harvest and everything would turn out okay because the weather patterns were predictable. But, with the rapid change of environment, farmers tend to seek alternative ways of ensuring the crops can survive during the whole growing period. One of these methods is by use of dam liners and it’s what we will be showing you how?

Dam liners offer waterproofing of dams, ponds, canals, tanks and ditches preventing loss of water to the environment. Dam liners for sale in Kenya come in various thicknesses i.e., 0.3 mm, 0.5 mm, 0.75 mm and 1 mm.

The main factors to consider when choosing the type of dam liner to use are;

  • The nature of the dam base – a dam base having stony surface will require a thicker dam liner. Whereas a thinner dam liner i.e., 0.3 mm can be used on a base having fine soils
  • The expected volume of water to be held – a big reservoir will hold a lot of water. In order to support the weight of the water without tearing, a thicker dam liner will be required. A thin dam liner can be used comfortably in small ponds and tanks.
  • The expected life time of the dam liner – if a farmer desires a dam liner that will last for a long time then a thick dam liner is recommended. Thin dam liners have short life expectations compared to thick dam liners 
  • The available budget – thick dam liners tend to be more costly than thin dam liners due to their high resistance to shear forces. The budget of the client should be a consideration. 

Advantages of dam liners for sale in Kenya 

Dam liners for sale in Kenya have a number of advantages that place them amongst the top products on the market. These advantages include;

  1. Dam liners are very resistant to shear forces and the strength of each type depends on the thickness of the liner.
  2. HDPE dam liners have a high resistance to ultra-violet rays. 
  3. Dam liners are very easy to clean and maintain. In case of damage, they can be easily repaired using a liner patch.
  4. Compared to other methods of lining dams and ponds, using a dam liner is much cheaper
  5. Dam liners are made to be chemical resistant preventing corrosion.
  6. Dam liners are built strong enough to resist plants’ roots from tearing into them.

Use of dam liners in fish farming.

Fish farming is an up coming enterprise which involves raising of fish in tanks or enclosures for human consumption. The growth of aquaculture  has resulted in an increase in dam liners for sale in Kenya.  Fish production occurs mainly on the top layers of water as a result of that, when it comes to making a fish pond a depth of less than 2 meters is preferred. 

 

•dam liners in Kenya

Water harvesting for irrigation using dam liners for sale in Kenya

 

With the increased unreliability of rain water, most farmers have sought other options to get past this hurdle. Irrigation is an efficient way to ensure that the crops are able to receive the right amounts of water in order to grow. For those located where rivers flow only in specific periods or where there are no rivers at all, they have to find other ways of ensuring water supply throughout the whole crop growing season. There are different types of dam liners for sale in Kenya which help in this problem. By building a reservoir and lining it with a dam liner, a farmer can be able to store all the water that he/ she will need for the entire growing period of the crop. 

How to size a water pan in relation to irrigation requirements

In order to choose the right dam liner for sale in Kenya it is important to determine the right size of liner that will be needed. The size of the dam liner is promotional to the size of the reservoir to be dug. The size of reservoir should be able to hold enough water to carry the crops through a prolonged drought period without any problems.

Size of the reservoir should also be able to accommodate both the water and sediments. This is because the reservoir built is usually open at the top. 

Things considered when designing  reservoir

  1. The current and future water requirements of the crops
  2. Water losses through evaporation and seepage
  3. The depth of the ground water – The base of the reservoir should be at least 1 m above the ground water 
  4. The volume of irrigation return water after an irrigation event. Irrigation return water refers to water that leaves the field back to the reservoir after water application. This volume varies greatly depending on the irrigation method used.
  5. The hydraulic retention time – It is the time taken for water to stay in a reservoir before it is used for irrigation. A longer hydraulic retention time helps in contaminant removal. 
  6. A slope ratio of 3:1 or 4:1 has been recommended for reducing the rate of bank erosion.

Eunidrip irrigation systems as a preferred dam liner supplier.

Why should you choose Eunidrip irrigation systems as your supplier of dam liners for sale in Kenya? At Eunidrip irrigation systems we care for our customers’ needs when it comes to selecting the best dam liners. The available dam liners come in thickness of 0.3 mm, 0.5mm and 1 mm. The standard dam liner we have comes with either a width of 6 m or 8 m and length of up to 100m. When your dam or pond has a width of more than 8 m it will mean two liners must joined together to reach the required width.

Dam liners for sale in Kenya advantages

There are various types of dam liners available in the market. These types include EPDM dam liners, PVC dam liners, HDPE dam liners and LLDPE dam liners. Here at Eunidrip irrigation systems we deal with HDPE dam liners which are more stable, chemical resistant, ultra violet resistant and weather resistant. Amongst the dam liners for sale in Kenya there are those that are made with recycled resin and those made from pure raw materials. Dam liners made from recycled resin get their raw materials from recycled water bottles, medical waste, plastic bags, greenhouse waste polythene etc. 

Disadvantages

As much this is helping in controlling pollution by plastic wastes, the dam liners produced have many challenges. Some of these challenges are; they are not stable and they can cause harm to fish when used in fish ponds. Since they easily breakdown, they will release toxic substances to the fish pond. At Eunidrip we deal with HDPE dam liners made from pure raw materials ensuring the customers gets the best out of their money. There are a few ways to check on the quality of dam liners for sale in Kenya.  These are:

  • Smelling the dam liner – liners made from recycled resin have a pungent smell
  • Checking whether the liner will float or sink when placed on water – a good quality dam liner will float in water where as a poor-quality liner will sink 
  • Visual check – a good quality liner will have a smooth surface. 

 

Environmental impact of collecting water using dam liners for sale in Kenya.

The use of dam liners in water storage has helped my people be able to overcome the problems associated with insufficient rainfall within the country. By using reservoirs lined with dam liners for sale in Kenya,  there can be sustainable water use in the country. This is especially useful in areas where rain falls for a short period of time and in large quantities. Dam liner stores reservoirs water which is later for irrigating the farm

By using dam liners for sale in Kenya it has now become possible to practice inland fishing. This has helped remove the previous obstacles associated with inland fish farming. The increase in inland fish farming has resulted in an increase in food in the country. In the case of very large dams lined with liners, the water stored can act as a heat sink helping in controlling the temperature. Dam liners are useful when treating water in sedimentation tanks and oxidation tanks. Dam liners used for wastewater treatment should always be in the perfect condition to avoid leakages. 

 

Water harvesting Dam liners

Water harvesting for irrigation using dam liners for sale in Kenya

With the increased unreliability of rain water, most farmers have sought other options to get past this hurdle. Irrigation is an efficient way to ensure that the crops are able to receive the right amounts of water in order to grow. For the farmers located near permanent water sources, they have a big advantage since they can always be assured of a constant supply of water. For those located where rivers flow only in specific periods or where there are no rivers at all, they have to find other ways of ensuring water supply throughout the whole crop growing season. There are different types of dam liners for sale in Kenya which help in this problem. By building a reservoir and lining it with a dam liner, a farmer can be able to store all the water that he/ she will need for the entire growing period of the crop.

How to size a water pan in relation to irrigation requirements

In order to choose the right dam liner for sale in Kenya it is important to determine the right size of liner that will be needed. The size of the dam liner will be determined by the size of the reservoir to be dug. The size of reservoir should be able to hold enough water to carry the crops through a prolonged drought period without any problems. The size of the reservoir should also be able to accommodate both the water and sediments. This is because the reservoir built is usually open at the top. Wind carrying dirt particles will deposit these particles in the water and also particles due to bank erosion will also be deposited in the reservoir. The consideration that should be taken into account when designing a reservoir are;

  1. The current and future water requirements of the crops
  2. Water losses through evaporation and seepage
  3. The depth of the ground water – normally a depth of more than 3 meters is recommended but that depends on the level of ground water. The base of the reservoir should be at least 1 m above the ground water
  4. The volume of irrigation return water after an irrigation event. Irrigation return water refers to water that leaves the field back to the reservoir after water application. This volume varies greatly depending on the irrigation method used.
  5. The hydraulic retention time – this refers to the time it takes water to stay in a reservoir before being used for irrigation. A longer hydraulic retention time helps in contaminant removal.
  6. A slope of ratio 3:1 or 4:1 is recommended to reduce the rate of bank erosion.

QUALITY IRRIGATION PIPES FOR CROP FARMING.

Quality irrigation Pipes for farming

Quality irrigation pipes for crop farming is a network of pipes used to convey water into the crops from a certain water source. Irrigation pipes are used as part of the conveyance system and distribution system of an irrigation scheme. The conveyance system provides water from the water source to the pump. The distribution system delivers water from the pump to the crops.

There are various types of irrigation pipes in the Kenyan market today.

  • Polyethylene (PE) pipes.
  • High-density polyethylene (HDPE) pipes.
  • Galvanized iron pipes.
  • Poly-vinyl chloride (PVC) pipes.
  • Low-density polyethylene (LDPE) pipes
  • PVC Lay flat hose

Popular Irrigation Pipes in Kenya

Quality irrigation Pipes for farming
Quality irrigation Pipes for farming
Poly-vinyl-chloride-PVC-pipes
Quality irrigation Pipes for farming

Polyethylene (PE) pipes

Polyethylene quality irrigation pipes for crop farming are made using thermoplastic material through extrusion.

Characteristics

  • Different sizes of pipes can be made.
  • PE pipes come in various colors, with standard black and blue colors
  • They are flexible and not easy to break, even in icy conditions.
  • Their toughness makes them be used on almost any surface.   

Polyethylene (P.E) pipes have different rating as follows:-   

  1. PN 2.5    
  2. PN 16
  3. PE  PN 4 
  4. PN 6

Details 

   Polyethylene pipes come in diameters ranging from 12 mm to 1200 mm and are rated in different classes depending on the pressures they can withstand. . The minor PN rating in PE pipes is PN 2.5, while the highest rating is PN 16. This means that a PN 2.5 PE pipe is most suitable for use with less than 2.5 bars of water pressure. A PN 16 PE pipe can be used for water pressures below 16 bars. The available PN classes in PE pipes are; PN 2.5, PN 4, PN 6, PN 10, and PN 16. Small PE pipes come in coils, whereas large PE pipes come in straight lengths.

 

 

 

Galvanized iron pipes

Galvanized iron pipes for irrigation are metallic pipes coated with zinc to avoid rusting and increase the longevity of the pipes. Galvanized pipes can be covered using two processes, i.e., hot dipping galvanizing or electro galvanizing. Pipes coated through the hot dipping process have a thick and uniform layer of zinc. The coat adheres firmly to the pipes, and longevity is assured. Galvanized pipes painted using electro galvanization process lack a smooth layer and have poor corrosion resistance. Although the electro galvanization process is a cheap method, the durability of the pipes is not assured. Nowadays, galvanized pipes in irrigation systems are being done away with. Studies have shown that when the pipes are used for a long time, they begin to rust and corrode on the inside. It is advisable to change the use of galvanized pipes to better quality irrigation pipes for crop farming.  Some of the problems associated with rust and corrosion build up in the galvanized pipes are;

cons

  1. Low water pressure – Due to the build-up of rust in the pipes, the frictional head loss will be significantly increased in the pipes. This will cause most systems to fail or work poorly.
  2. Uneven distribution of water – corrosion in the galvanized pipes will build up differently in various parts of the pipes. This uneven build-up will result in uneven distribution of water due to different resistances in the system.
  3. Blockage of sprinkler nozzles and drip emitters – Drip emitters and sprinkler nozzles are very sensitive to particles in the water. Although the filter will filter out soil particles and other materials, the rust inside the pipes will be carried by the water to the drip emitters or sprinkler nozzles.
  4. Leaks – continued corrosion in the galvanized pipes will result in leakages. Leakages reduce the water pressure in the irrigation system, reducing efficiency.

PROS

  • Durable.
  • Can be used in large project to convey water.
  • High pressure resistance.

Polyvinyl chloride pipes (PVC)

PVC pipes are quality irrigation pipes for crop farming made out of polyvinyl chloride. They are light and resistant to corrosion. Most PVC pipes come in either black, white, or grey color and lengths of 6 m. PVC pipes come in various diameters, ranging from 16 mm to 110 mm. They are also grouped according to their pressure classes, like in the PE pipes. The lowest pressure class in PVC pipes is PN 4, and the highest-pressure class available at Eunidrip irrigation systems is PN 20. PVC pipes are not suitable to be used above the surface. This is because PVC pipes are affected by sunlight and become brittle. The best way to counter this problem is by burying the pipes or if they are needed above the surface, then using foam pipe insulation or latex paint is recommended. 3 to 4 coats of latex paint are recommended to protect the PVC pipes against sunlight. Another reason to bury the PVC pipes is to protect them against mechanical damage on the surface.

What are the advantages of using PVC quality irrigation pipes for crop farming?

  1. They are light, making them easy to transport and install
  2. They have corrosion resistance
  3. The inside of PVC pipes is made to be smooth, reducing pressure losses in the system
  4. PVC pipes can be recycled, helping in protecting the environment
  5. There are no leakages in the pipes when sealed properly
  6. They are tougher than PE pipes when it comes to the stress by flowing water.

Various fittings are bought with PVC pipes to assist in laying the irrigation pipes on the farm. These fittings include; PVC elbows, PVC tees, PVC sockets, PVC end caps, PVC bushes, PVC reducing sockets and reducing sockets and bushes, etc.

Low-density polyethylene pipes

LDPE pipes are transparent, flexible, non-toxic, quality irrigation pipes for crop farming. They are corrosion, heat, and chemical resistant. Compared to PVC pipes, they don’t have excellent resistance to chemicals, e.g., chlorides and solvents. However, LDPE pipes are much cheaper than PVC pipes. The temperature ranges that LDPE pipes work efficiently range from – 500 C and 800 C. The melting temperature of LDPE pipes is 120 0 C. LDPE pipes have high compressive strength, flexibility, and high expansion properties than high-density polyethylene (HDPE) pipes.

High-density polyethylene pipes

High-density polyethylene pipes are the most preferred types of pipes to be used for irrigation presently. They are high-quality irrigation pipes for crop farming that operate over a wide range of temperatures. They are black due to carbon black added during manufacturing. The main purpose of carbon black is to help in protecting the pipe against ultraviolet rays. HDPE pipes are made through the extrusion process and come in diameters ranging from 16 mm to 1600 mm. New HDPE pipes come in standard lengths of 6 m to 100 m. HDPE pipes are classified according to their pressure ratings, and the following classes are available; PN 2.5, PN 4, PN 6, PN 10, PN 16, PN 20, and PN 25. Joining one HDPE pipe to another can be achieved by either welding or using HDPE fittings. These HDPE fittings include; tees, elbows, couplings, reducing couplings, male and female adapters, and end caps.

Advantages of HDPE pipes as quality irrigation pipes for crop farming are;

  1. HDPE pipes have high flow rates due to the smooth nature of the inner walls of the pipe
  2. HDPE pipes operate over a wide range of temperatures, i.e., between -2200 C and 1800
  3. These high-quality irrigation pipes for crop farming are light and easy to transport.
  4. Simple methods of joining HDPE pipes are available
  5. Unlike in LDPE pipes, there is no leaching in HDPE pipes
  6. HDPE pipes can be laid above the soil surface since they have resistance to ultraviolet rays
  7. HDPE pipes are resistant to chemicals

The only limitations that HDPE pipes have are that they have a high thermal expansion, they are highly flammable, and they are susceptible to stress cracking.

PVC lay flat hose

These water conveyance pipes are woven continuously using a high tensile strength polyester for reinforcement purposes. These high-quality irrigation pipes for crop farming operate within a temperature range of -100 C and 600 C. They come in lengths of up to 100 m, and the working pressures range from 8 to 40 bars. PVC lay flat can be classified according to the following ways.

  1. According to working pressures – lay flats hoses can be grouped either as type 8, 10, 13, 16, 20, 25,30, or 40. The number represents the maximum pressure the lay flat can withstand.
  2. According to inner diameter – groupings according to the inner diameter are 25-1″, 40-1.5″, 50-2″, 65-2.5″, 80-3″, 100-4″, 125-5″, 150-6″, and 200-8“.
  3. According to the number of layers of strips – PVC lay flats hoses grouped according to number of layer strips are single stripped PVC lay flats and double Stripped PVC lay flats
  4. According to the lay flat hose material – lay flats grouped according to hose materials are naturals rubber, polyvinyl chloride, polyurethane (PU), ethylene polymer terpolymer (EPDM), and the double-sided adhesive. The lay flat hoses made from EPDM are oxidation, ozone, and corrosion-resistant. Lay flat hoses made from PU materials are much softer.
  5. According to the use – PVC lay flat hoses are used in various places. These areas are fire protection, irrigation, mine rescue, road engineering, and river dredging.

The advantages of using a PVC lay flat are:

  1. They are light and flexible
  2. They are durable and strong
  3. They are ultraviolet protected
  4. They are made to be tough, resisting abrasions.
  5. They have a burst pressure three times stronger than the working pressures.
  6. They don’t age
  7. They come in a variety of colors.

Suction pipes

Suction pipes are quality irrigation pipes for crop farming mainly used on pumps to deliver water from the water source. Short suctions pipes are mostly preferred because of energy efficiency and to avoid cavitation. A short suction pipe will ensure the pump uses less energy during suction. Cavitation occurs when air pockets are created due to changes in pressure. When the bubbles explode, they send shockwaves to the surrounding components causing damage.

Factors to consider when choosing quality irrigation pipes for crop farming.

There are several factors to be checked to choose the right material for quality irrigation pipes for crop farming. These factors include;

  1. The water pressure – different irrigation methods require different water pressures to work effectively. Drip irrigation system requires less water pressure than sprinkler irrigation systems. If high water pressures are expected, it’s best to use irrigation pipes with high-pressure ratings.
  2. The nature of water being transported – fertilizer is usually added to the water in most irrigation systems to ensure even distribution of nutrients to the plants. If this method is going to be applied, then it is best to use irrigation pipes with high chemical and corrosion resistance. Also, when using water with high chlorine contents, it is best to use pipes with high chemical and corrosion resistance.
  3. Ease of installation and maintenance – a system with the least challenges should be used.
  4. Pipe placement – if the irrigation pipes are going to be placed above the soil surface, it’s best to go for ultraviolet resistant pipes, e.g., HDPE pipes. Pipes that are going to be buried should be buried at the appropriate depth to avoid damage to the pipes.
  5. The water flow temperature in the system – each quality irrigation pipe for crop farming has a temperature range where the pipe has optimum performance. The temperature of the water being used in the irrigation scheme should be checked. The minimum and maximum temperatures of irrigation water determine the type of pipe to be used.
  6. The expected life of the irrigation pipes – high-quality irrigation pipes have a high expected lifetime compared to low-quality irrigation pipes.
  7. Cost of the irrigation pipes – high-quality pipes are more expensive than low-quality irrigation pipes. The amount of money a farmer has, determines the type of pipe to be purchased.  
  8. Availability of valves and fittings – some irrigation pipes have fewer fittings and valves to choose from, whereas others have many.

Price of quality irrigation pipes for crop farming in Kenya:

There are a variety of quality irrigation pipes for crop farming available for sale. At Eunidrip, we deal with the country’s best quality PVC and HDPE pipes. The prices vary depending on the size of the pipe. The following is a list of the available HDPE pipes and their prices at Eunidrip irrigation systems.

Pipe diameter

Length per roll(meters)

Price per roll

16mm

100

1700

20mm

100

3300

25mm

100

3900

32mm

100

5500

40mm

100

9000

50mm

100

12500

63mm

100

18000

PVC pipes available for sale at are:

Pipe in millimeters

Pipe size in inches

Running length in meters

Price

20

1/2

6

110

25

3/4

6

190

32

1

6

300

40

1 ¼

6

400

50

1 ½

6

510

63

2

6

650

75

2 ½

6

950

90

3

6

1,050

How to repair quality irrigation pipes for crop farming

For optimum pressures to be attained in an irrigation system, the irrigation pipes must not have any leakage. Leakages result in pressure losses in the pipes. It is important to know how to repair various irrigation pipes to save on the costs of buying new pipes. The following are ways to repair different quality irrigation pipes for crop farming.

PVC pipes

 PVC pipes are quality irrigation pipes for crop farming that are very easily damaged. Minor leaks can easily be repaired. However, if the damage is too much, the whole pipe needs to be replaced. Common reasons as to why PVC pipes leak are:

  1. During installation, the PVC pipes were not sealed properly.
  2. The use of wrong PVC cement – PVC cement refers to the adhesive glue used to join two PVC pipes.
  3. Damage due to freezing of the PVC pipes – PVC pipes can become brittle with exposure to freezing temperatures. At this time, it is very easy to damage the PVC pipes.

PVC pipes can be repaired in a variety of ways. Examples of these ways are;

  1. By use of fiberglass resin tape or cloth – Fiberglass resin is water-activated, and it hardens when placed where the leak is. Before applying the resin, the damaged part is cleaned, and the tape is wrapped around the damaged area while it is still wet. The resin takes about 15 minutes to harden, sealing off the damaged part. Fiber resin cloth is used to make more permanent repairs on the pipe. The damaged part is cleaned first and made to be rough to create an adhesive surface. The resin cloth is placed over the damaged part, and ultraviolet light is used to cure the resin.
  2. The second method of repairing PVC quality irrigation pipes for crop farming involves epoxy- Epoxy is a viscous fluid used to repair PVC pipes. To start the repairing process, clean and dry the damaged part first. Afterward, mix the epoxy according to the instructions and apply it to the damaged part. Let it cure for about ten minutes and confirm if there are any leaks.
  3. Using rubber and silicone repair tape – this tape seals a leak by using compression. The tape is wrapped tightly around the damaged part, adhering to itself as it’s rolled around the damaged part.
  4. By using rubber tape and hose clamps – in this method, rubber is used to wrap around the damaged part, then the hose clamps are separated, placing them on the damaged area. This method is used to repair small leaks, and it is used for temporary fixes. As time goes by, the hose clamps lose their effectiveness, and leaking will resume.
  5. Replacement – the PVC pipe should be replaced when the damage is too much. The first thing to be done is to cut off the damaged part. The part is cut one inch more to the left and the right. The part to be repaired is cleaned and dried. Dry fit the replacement pipe to ensure that the pipe is properly secured. A PVC prime solvent is then applied to the inside of the replacement pipe and outside the existing pipe. Apply glue to the exposed PVC pipe inside the replacement pipe and insert the existing pipe into the replacement pipe. Hold the pipe for about 15 seconds to ensure the bond is strong.

HDPE pipes

HDPE pipes are quality irrigation pipes that are pretty easy to repair for crop farming. Like PVC pipes, the extent of the damage determines the action to be taken. If the damage to the pipes is too much, then the pipe must be replaced. If the damage is minor, repairs can be done. The first step of any repair is to locate the damaged part. If the HDPE pipes are above the soil, it will be easy to locate the leak. If the HDPE pipes are buried, then areas with a lot of water can indicate where the leak is. The reasons that can result in leakage of HDPE pipes are worn-out rubber seals on the couplings and mechanical damage to the pipes. To fix a leak in HDPE pipes, the following procedure is to be followed:

  1. Turn off the water to avoid water wastage while you dig out the pipe.
  2. Digging – this is done for HDPE pipes that are installed under the soil. Dig carefully where you suspect the leak is to avoid more damage to the pipe.
  3. Check to confirm that you have found the leak and plan on how to cut the pipe.
  4. Use a pipe cutter to cut the pipe and install the necessary fittings. We use a clamp or a coupling to join the two cut parts
  5. Tighten the clamps to ensure there is no more leakage.

PVC lay flat hoses

PVC lay flats can be damaged due to poor storage or improper operation. These quality irrigation pipes for crop farming can be repaired easily if the hole is small. The first thing to do is find an old lay flat hose and cut part of it. The cut part should be larger than the hole to be repaired. Electric soldering is done on the cut part, joining it to where the hole was. A PVC lay flat hose can also be repaired using high-quality glue. If the part to be repaired is on a joint, it is necessary to cut off the joint and retie it.

Quality irrigation pipes for crop farming layout

In irrigation schemes, pipes of different sizes and types are arranged to achieve efficient water distribution. Pipes of the same size are used to maintain water pressure in irrigation pipes. Irrigation pipes can also be arranged with decreasing diameters from the pump to the farm. By doing this, the pressure in the irrigation pipes increases. It is unconventional to increase the size of irrigation pipes from a small diameter to a larger diameter since there will be a lot of pressure loss. Various factors affect the layout design used in quality irrigation pipes for crop farming. These factors are topography, the plants to be grown, the irrigation system used, and the size of the farm.

Topography

The topography of an area greatly affects the layout design. When designing an irrigation scheme, the highest and lowest points on the farm are first determined. To reduce the resistance of flow by water, the tank is placed at the highest point so that water can flow by gravity. The main lines are arranged along the slope, whereas the laterals are across the slope. By placing the mainline along the slope, gravity assists in delivering the water. Laterals are placed across the slope to avoid water accumulating on one end.

The plants to be grown

Various plants have different characteristics that determine the irrigation method to be used. Tree crops like avocados, mangoes, and pawpaws use a button dripper irrigation design, whereas tomatoes, lettuce, and beans perform best with a drip irrigation system.

Size and shape of the farm

In a large farm, bigger and a lot of pipes will be used compared to a small farm. In a big farm, the flow rates required are high. To achieve this, pipes of large diameters are needed. The shape of the farm determines how the pipes will be laid. A good design will ensure water is available at every corner of the farm, no matter the shape.

Irrigation system being used

The piping network done on each irrigation method vary greatly.

Source of water

The source of water affects the design of quality irrigation pipes for crop farming to be used. Most irrigation designs start from the source of water, which will determine how the pipes will be laid.