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.

SOLAR PUMPS FOR IRRIGATION

SOLAR PUMPS FOR IRRIGATION

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Solar pumps for irrigation are pumps that use photovoltaic panels to produce power which is used in running pumps for irrigation. Unreliable rainfall in Kenya has led to many farmers seeking alternative ways of ensuring reliable water supply to the farms. Many have opted to drill boreholes and to pump from rivers and streams to their farms. With the rising fuel prices in the world, the use of solar pumps seems like the best way to go. These types of pumps are especially useful in areas with no electricity, where the supply of electricity is not efficient, and in areas where the source of energy being used is not enough e.g., wind energy. These types of pumps have the added advantage of having low maintenance costs.

Types of solar pumps for irrigation

There are major types of solar pumps for irrigation available;

  1. Surface solar pumps.
  2. Submersible water pumps.
  3. DC solar pumps.
  4. AC solar pumps.

Surface solar pumps for irrigation

Surface solar pumps for irrigation are mostly used in shallow wells, ponds, or streams to pump water to farms. They are used when the depth of the well used is less than 15 m and the water can be pumped for a distance of 60 m or more. The impeller in surface solar pumps is mounted directly on the shaft and the motors used are permanent magnetic direct current motors (PMDC). These motors achieve high working efficiencies and are easy to maintain.

Submersible solar pumps for irrigation

These types of solar pumps for irrigation are used in deep wells where the depth is more than 15 m but less than 50 m. Submersible solar pumps can achieve high heads of up to 450 m depending on the size of the pump used. They come equipped with brushless direct current motors (BLDC)or alternating current induction motors. These motors are capable of achieving high torques and efficiencies.

DC solar pumps for irrigation

They are solar pumps that use direct current from the solar panels. The energy generated is capable of pumping water from wells having depths of up to 112 m

AC solar pumps for irrigation

These types of solar pumps make use of alternating current making an inverter necessary in the system. It is best to use solar pumps together with storage tanks. Solar’s are affected by the weather. Water can be stored in the tanks for irrigation use reducing the risk of bad weather.

Components of solar pumps for irrigation

Solar pumps for irrigation in Kenya consist of the following components;

panels, controller,  pump.

Solar panels

The function of solar panels in a solar pump for irrigation is to absorb sunlight and convert it to direct current. This process is achieved by silicon and conductors on the solar panels.

The type of solar panel and number of panels to use varies greatly depending on the following factors;

  1. Volume of water needed to be pumped – if the volume of water needed is a lot, then powerful or more panels or will be needed to generate the required power.
  2. Geographical location where the solar pump is to be used – when solar pumps are used in regions that receive minimal sunlight in the day, it is best to increase the power generated during the few sunlight hours. This can be achieved by using more panels or using more powerful solar panels. In areas like deserts or semi-deserts which receive a lot of sunlight then fewer solar panels can be used.
  3. Ratings on the solar panels – the ratings on the solar panels affect the number and types of solar panels to use. This is because the rating of the panels determines how much power can be generated by each panel.
  4. Head of water needed to be achieved by the solar pumps – for a solar pump to pump water great distances then more power will be needed. This fact determines the number of panels that will be needed and the type of panels.

What factors affect the power generated by solar panels?

The following factors affect the amount of power generated by the solar panels in solar pumps for irrigation.

  • Solar insolation – this refers to the amount of sunlight received within a specific region in a day. It is measured in kilowatt-hours per meter squared per day (KWh/m2/day ). The time of the year and the geographical location affect this factor.
  • Solar power – The panels can be connected either through a series connection or a parallel connection. Panels connected in series have a voltage equal to the sum of all the individual panel voltages while the current of the whole system is equal to the current of one panel. Panels connected in parallel have an overall current equal to the sum of each panel’s current and a voltage equal to the voltage of one panel.
  • Orientation of the solar panel – for maximum power generation, the solar panels should be facing the sun directly. The solar panels can be designed to be able to switch their angle according to the sun’s position maximizing on the available sunlight.
  • Sunshine hours – this is affected by the geographical location and the weather patterns within an area. There will be less power generated in areas that receive cloudy or rainy weather during the day compared to regions with hot and clear weather. In the northern and southern hemispheres where they experience the four seasons, maximum power will be generated during summer and little or no power will be generated during winter.

Controller

The main purpose of the controller is to regulate the current and voltage of the power produced by the solar panels. Since the light offered by the sun greatly fluctuates, the controller is used to take care of these fluctuations. The controller helps in starting the pump when the sunlight is low and also helps in preventing overheating of the motor during high sunlight quantities. The weather can be unpredictable at times and to cater for that, other sources of power can be connected to solar pumps for irrigation. These connections are made on the controller and examples of power sources that can be added are generators, batteries, and wind machines.

Solar pumps

Solar pumps for irrigation can either use direct current (DC) or alternating current (AC).  For solar pumps using direct current, an inverter is not needed. Those that use alternating current need an inverter to change the DC power generated to AC.  Solar pumps are designed to operate at a range of voltages between 24 v and 300 v. This range caters for even when the sunlight is low. The solar pump chosen should be able to overcome the total head to be pumped and the frictional losses in the system.

What is the working principle behind solar pumps for irrigation?

The photovoltaic panels in solar pumps for irrigation are able to convert the sun’s radiant energy to electricity. The electricity produced is direct current (DC) and there is need to be converted to alternating current (AC). Alternating current is the form of electricity that is used to run the pump and an inverter is used to convert the direct current to alternating current. The inverter is also capable of controlling the voltage and frequency of the of the power supply according to the sunlight intensity. The now converted alternating current is then used by the motor to run the pump.

Determination of the number of solar panels needed in solar pumps for irrigation

The number of panels needed to run solar pumps for irrigation depends on the power required by the pump. The power needed by the pump is usually indicated on the pump by the manufacturer. In order to find how much solar power is needed we use the following equation:

Solar energy needed by pump = load of the pump × hours of sunlight received per day × 1.5

The load of the pump refers to the amount of electricity needed to run the pump. Most countries receive an average of 5 hours of sunlight daily, hence we compute using 5 hours. The value 1.5 is used as a factor of the safety of the pump to ensure a constant power supply.

To find the total watts that the solar panels will need we compute using the following formula:

Solar panel wattage needed = total load of the pump/ average hours of direct sunlight

Solar panel output per day

Most solar panels come either having 60 cells or 72 cells. There are even some which come having 96 cells.  In the 60-cell panel, the cells are arranged in a 6 × 10 grid whereas in a 72-cell panel they are arranged in a 6 × 12 grid.  The 60-cell panel measures 1 m by 1.67 m whereas the 72-cell panel measures 1 m by 2 m. A 60-cells solar panel produces 270 – 300 watts per hour and a 72-cells solar panel produces 350 – 400 watts per hour. In order to compute the solar panel output per day we use the following relation:

Solar output per day = solar panel power produced per hour × average hours of sunlight in  day × 75%

The 75% represents the efficiency of the solar panel system.

Size of solar panel battery needed

A battery is required especially if water pumping is also being done during the night. The battery will also help when the weather conditions are not favorable i.e., rainy or cloudy weather. We use the following formula to calculate for the size of battery  needed.

Size  of battery needed = average power used per night + (average power used per night × 30% )

The 30% increase in the computation is to cater for cloudy or rainy days.

Size of inverter required

An inverter is an important device in solar power pumps for irrigation. It helps in changing the DC current from the panels to the AC current required by the pump. In order to find out the size of the inverter needed; the array must be found. The solar array refers to the amount of energy that a 1KW solar panel can produce. The solar array is computed using;

Solar array = Total solar energy produced per day/ Solar panel wattage

The size of the inverter is usually recommended to be of the same size as that of the solar array. That means the solar array found in the size of the inverter that is needed.

Advantages of solar pumps for irrigation

The advantages of using solar pumps for irrigation are:

  • The use of solar pumps is helping in reducing global warming and protecting our natural resources. Solar pumps use the sun’s energy reducing the use of fossil fuels. This has helped in protecting non-renewable resources and reducing harmful emissions.
  • Solar pumps for irrigation are durable and perform efficiently
  • The operating cost of solar pumps is low. Solar pumps don’t need fuel to work and this has helped in reducing costs.
  • Maintenance  done on solar pumps is very minimal
  • Portability of the solar pumps is very easy

 Challenges encountered when using solar pumps for irrigation?

The main challenge  encountered  using solar pumps in irrigation is power supply. The fluctuations in sunlight mean the power generated also is going to fluctuate. However, hybrid system maintains a steady flow of power when the charge is not enough. By using tanks to store the water pumped, it is also possible to counter the problem of sunlight fluctuation. This method of pumping water for irrigation is a little bit costly to initially set up. However, the long-term savings done when using this system compared to diesel powered pumps are a lot.

Drip irrigation system design

DRIP IRRIGATION SYSTEM DESIGN

Description

Drip irrigation system design is a method of irrigation where water is applied slowly and frequently, directly into the vicinity of the root zone of the crop wetting only a very limited fraction of total surface area and depth of the soil. Water is applied close to plants so that only part of the soil in which the roots grow is wetted, unlike other systems of irrigation, which involves wetting the whole soil profile. With drip irrigation water, applications are more frequent than with other methods and this provides a very favorable high moisture level in the soil in which plants can flourish.

Drip Irrigation system is based on two main fundamental concepts of irrigating only the root zone of the crop rather than the entire land surface and also maintaining the water content in the root zone at near optimum levels

Drip irrigation system is accomplished by use of pressures ranging from 15 to 200 kPa (1.5 to 20 m head of water) to drip water one-drop-at-a-time onto the land or into the root zone and also to spraying water as a fine mist over portions of the land surface.

Factors to consider when selecting the drip irrigation system design.

Drip irrigation system is one of the cheapest and easiest ways of irrigation a farmer should prefer. While selecting this type of irrigation system the following factors should be considered.

  1. Types of crops

Drip irrigation system design for the Chive

Drip irrigation system is most suitable for row crops including vegetables, fruits, tree and vine crops where one or more emitters can be provided for each plant. Generally, only high value crops are considered because of the high capital costs of installing a drip system.

  1. Nature of the land.

Drip irrigation system is adaptable to any farmable slope. Normally the crop would be planted along contour lines and the water supply pipes would be laid along the contour also. This is done to minimize changes in emitter discharge as a result of land elevation changes.

  1. Suitable soils

Drip irrigation system is suitable for most soils. On clay soils water must be applied slowly to avoid surface water ponding and runoff. On sandy soils higher emitter discharge rates will be considered to ensure adequate lateral wetting of the soil.

  1. Suitable irrigation water

Drip irrigation system requires water that is clean and free of sediments, algae, fertilizer deposits and undissolved chemical particles. This is because all emitters have very small waterways with diameter ranging from 0.2 to 2mm, which can become blocked if the water in dirty. Dripping water to individual plants also means that the method can be very efficient in water use. For this reason, it is most suitable when water is scarce.

Components of Drip irrigation system design.

Drip irrigation system is comprised of the following basic elements:

Control head (Central Control).

This comprises of valves, discharge, and pressure meters. It provides a means for Control and regulation of discharges, and pressures, including non-return valves and air vents. It also has an automation and control equipment, filters and dissolved fertilizer applicators. Depending on the size of the system, there may be several control heads, each serving an irrigation unit.

The Main pipe

This is generally a rigid pipeline made from HDPE, asbestos cement or concrete. The main pipe is almost always buried and conveys water from the source to the main control points in the field.

The Sub-main pipe

This is a multi-valve pipe distributing irrigation water to the various sub-units within a unit. A sub-unit in this case represents an area which simultaneously receives irrigation water from a single control point and which is being controlled by a valve on the sub-main.

It is made up of rigid black polyethylene pipe which in most cases laid on the ground surface, with a diameter ranging between 32mm to 90mm (1.25” to 3.5”), at a pressure of 4 atm.

When designing the sub main line, it is good to consider several factors which include topography of the land, field geometry, water supply and the uniformity required.

The Auxiliary or Manifold pipe.

This is either a flexible (soft) or rigid pipe of high density polyethylene type, generally 20 to 75 mm diameter, which distributes water between the laterals belonging to a single sub-unit.

The manifold and its lateral are designed and operated as a single unified system which is controlled by a single valve.

 Lateral (or Drip line) pipe.

This is basically a flexible (soft) polyethylene or PVC pipe buried or laid on the ground surface and which carries emitters. Its diameter ranges from 12 to 25 mm (0.5 to 1 in) and the pressure rating about 4 atmospheres. A typical trickle system may have up to or more than 10 km/ha of laterals.

The Emitters.

An emitter is a device or system element which makes the drip irrigation possible by providing irrigation water at low flows and atmospheric pressure. The performance of emitters determines to a large extent the efficiency of the system. Since their number is usually very high (from 2,000 to 20,000 per ha,

In Drip irrigation system, the most suitable emitters used are selected based on the following factors such as low in cost, uniform in structure and operation, simple to manufacture, and install, should be able to maintain low problematic at standard operating pressure (3 to 30 m), and should be able to produce a constant low-rate water supply at varying line pressure change.

The Specification of Emitters used in Drip Irrigation System design.

  • There are numerous designed specifications of an optimum emitter used in drip irrigation system:
  • It should be available in small increments of discharge on the order of 1 L/h.
  • The flow should be controlled within narrow limits as a function of operating pressure to properly balance applied water with crop water use;
  • The emitter should be able to resist degradation due to temperature fluctuations and solar radiation.
  • The operating pressure should be 2 to 5m (for low pressure) and 8 to 15 (for high pressure).
  • The discharge rate of emitters should range between 4 liters per hour (for low rate).4 to 10 liters/hour (for medium discharge), and beyond 15litres per hour for high discharge.
  • Should be able to offer flow regime of laminar flow, turbulent or partially turbulent.

The operating principle of Drip irrigation system design.

A drip irrigation system is usually permanent. When remaining in place during more than one season, a system is considered permanent. Thus it can easily be automated. This is very useful when there is little labour force. However, automation requires specialist skills and so this approach is unsuitable if such skills are not available.

With drip irrigation system, water can be applied frequently or every day if there is possibility. This can provide very favorable conditions for crop growth. However, if crops are used to being watered each day they may only develop shallow roots and if the system breaks down, the crop may begin to suffer very quickly.

The wetting patterns of drip irrigation emitters.

Drip irrigation only wets part of the soil root zone. This may be about, low as 30 – 40% % of the volume of soil wetted by the other methods of irrigation. The wetting patterns which develop from dripping water onto the soil depend on discharge and soil type.

Drip irrigation is not a substitute for other proven methods of irrigation. It is just another way of applying water. It is best suited to areas where water quality is marginal, land is steeply sloping or undulating and of poor quality, where water or labour are expensive, or where high value crops require frequent water applications.

 

Specific problems associated with drip system of irrigation.

As a matter of fact, Drip irrigation system being that it is cheap and easy to install, it is also associated with some of the emerging problems and challenges. These challenges are as mentioned below.

Emitters or drippers clogging effect.

The most serious problem in proper design, operation and maintenance of drip system of irrigation is emitter clogging. The orifices of drip system emitters or drippers are extremely small compared to the once in other systems of irrigation. There is therefore, high potential for emitter clogging by particulate, chemical precipitates, and bacteria. Emitter clogging can have severe impact on crop development because of the careful balance between crop water requirement and emitter discharge built into the design of trickle irrigation systems.

Solutions to problems associated with emitters clogging in drip irrigation system.

Criteria to handle the susceptibility of water supplies to emitter clogging should be developed in order to enable the designer to make decisions about the utility of water supplies that is necessary for drip irrigation. These criteria can help the designer in deciding whether drip irrigation system is the most adaptable system for a particular water supply and what type of filtration and water treatment devices may be required depending on the severity of the potential clogging problem.

 

  1. Use of appropriate filtration system.

Filters should be used to remove undesirable material from the water supply before it enters in the distribution system and creates potential for emitter clogging. Some type of filtration system is required on virtually in any drip system to ensure efficient system operation. Different types of filtration devices are effective in removing different size material from water source. The filter should be sized based on the emitter opening and the type of material to be removed. The most common filtration systems used for trickle irrigation systems Includes media or sand filters, Screen filters and Centrifugal filtration systems.

  1. Bacteria Treatment

Drip irrigation distribution systems can be clogged in a very short time by bacteria slime which blocks the distribution system.

High bacteria concentrations require treatment by bactericides, which contains chlorine or other compounds which must remain in contact with the water source long enough to kill off the bacteria. Normally 10 – 30 minutes of contact in a solution with free residual chlorine concentrations of 1 mg/L is adequate.

  1. Chemical Treatment

Chemical treatment is required to reduce the potential for precipitation of insoluble salts at the orifice and internal parts of emitters which causes clogging.

These precipitates are commonly caused by the reactions of soluble calcium and bicarbonates in the irrigation water, producing calcium carbonate.

The normal procedure to inhibit this reaction is to control the solution pH by addition of various acids recommended for use.

  1. Fertilizer Injection Systems

Drip irrigation system designs are particularly adaptable to fertilizer injection into the distribution system. This is because the water is applied directly to the plant root zone.

This leads to efficiency of fertilizer use, reduced energy and labour costs, and flexibility in field management

However, care must be exercised to prevent the fertilizer from corroding the distribution system components.

It should also be noted that due to water supply, algae growth and bacteria slime problems may occur. These can cause clogging emitters and screen and filter blockage.

  1. Operation Procedures of Injection Equipment

The basic principle of operating fertilizer and chemical equipment injection systems is that the material should not be allowed to set in the lines when the system is not operating.

Advantages of drip irrigation system.

Drip irrigation system has got various benefits to the farmer as follows.

  • Distribution of water is at the optimum level.
  • Minimization of Fertilizer or nutrient loss  during application.
  • Weeds effect are minimized since there is no water available for them
  • Drip irrigation enables the farmer to achieve maximum crop yield.
  • High efficiency of Fertilizers usage.
  • Drip irrigation ensures minimum operating cost
  • Reduction of soil erosion
  • High water infiltration rate into the soil
  • High seed germination rate
  • We can use recycled water safely.
  • We can irrigate water in irregular shaped lands.
  • low energy operation rate

Disadvantages of drip irrigation systems.

  • Initial cost of operation is relatively high especially for poor farmers.
  • Clogging effect is a very disgusting issue in drip systems of irrigation.

Irrigation method for dragon fruit farming in Kenya

Irrigation method for dragon fruit farming in Kenya

Dragon fruit under irrigation system
Dragon fruit under irrigation system

Dragon fruit is a fruit that is increasingly becoming popular among the farmers because of its value and the simple management practices as compared to other known fruit plants thus need for appropriate irrigation method for dragon fruit farming in Kenya. The plant is a native of Mexico and Central America but current it is grown worldwide.

Many people may refer to this fruit as pitaya, pitahaya and strawberry bear but its scientific name is Hylocereus Cactus or Honolulu queen which is believed to be nocturnal plant because it opens its flowers at night but during the day, they remained close.

There are various types of the dragon fruit but the mostly recognized have got bright red skin with green scales that looks like a dragon and the white pulp with black seeds.

The fruit is widely known for its mild flavor sweetness

How to prepare land for drip irrigation for dragon fruit farming in Kenya

Land preparation for drip irrigation for dragon fruit farming in Kenya is a process that involves several activities which may include, plowing and breaking of soil particles or the clods and addition of important soil nutrients. The purpose of these activities is to improve crop/plant growth and development.

dragon fruit
Dragon fruit

Land preparation ensures that there is sufficient water, heat, oxygen, and other important soil nutrients. This process will allow the soil to be more compressible to allow the penetration of the roots. These involves the use of disc harrows, ploughs and drillers.

When preparing land for irrigation for dragon fruit farming in Kenya, there is no use of raised beds since they are less important.  Beds are only recommended when using the drip line or the drip tape because this piping require generally level area in order to discharge water accordingly and to allow ease movement of the farm operators unlike the irrigation method for dragon fruit which levelling off the ground is unnecessary. Moreover, raised beds also play a major role in drainage and aeration


Factors to consider when selecting proper land for irrigation of dragon fruit farming in Kenya

  1. Generally sloping land to minimize clogging in case of heavy rainfall
  1. This includes ease of access to relevant infrastructure which may include electricity, good road network to allow ease of moving farm inputs and produce
  2. Labor and expertise: Expertise and labor are very critical when doing preparation for drip irrigation for dragon fruit farming in Kenya and may include skilled or non-skilled.

Labor and expertise go along with the culture of a specific community in and around the farm.
Labour is a major component of production and its cost determine the success or failure of your enterprise

4. Security.

The farm should be well secured from thieves, stray animals, rodents and other disease-causing organisms. This can be done by erecting fence around the farm or employing the watch guard to care for the farm.

When doing land preparation for drip irrigation in Kenya, the area should be free from rodents because rodents are the major drip tape/ drip line destroyers. To keep these rodents away, the nearby bushes should be cleared and pesticides sprayed.

5. Soil characteristics and crop climatic conditions.

Different crops do well in different soil and climatic conditions. Some crops do well in acidic soil.

While others do well in a basic or alkaline environment. On the same note, high land crops cannot do well in lowland areas unless special conditions are provided and if these conditions have to be reversed proper and special conditions should be provided.

These special conditions may include soil treatments and irrigation or using specialized equipment when installing your drip system e.g. venture injector


The procedure of obtaining a good bed for the drip irrigation for dragon fruit farming system

As stated earlier, dragon fruits are rowed and column fruits however, they can be grown in an irregular form since watering of these plants depends on water pump horse power and the piping systems. Since majority of the pipes are flexible, the arrangement of the plants does not matter.

The plowing should be done along with the land/garden during the first plowing and across during the second plowing.
This will ensure microorganisms and weed seeds are brought above the soil and exposed to the sunlight.
On exposing these it ensures faster growth of weed seeds due to warmth. After germination of the weed seeds due to favorable conditions brought by sunlight, use the recommended herbicides to kill the weed. Get recommendations from a qualified agronomist.
Do final plowing to bury the dead plants into the soil. The weed will later decompose/rot to add nutrients to the soil.

Considering the spacing of the dragon fruits, use the drillers to make holes to specific depths. The holes depend with the number of plants one is willing to plant and the management pattern to be applied.

steps of obtaining the best depth for drip irrigation for dragon fruit farming in Kenya

 

In hole depth preparation, the standard and most recommended bed sizes range from 0.3 meters (0.3m) for short season crops and sometimes to 0.5 meters (0.5) meters

The most convenient path width should be between 4m to 5m. This will ensure major parts of the land are put under cultivation.
After the selection of the convenient bed width and the paths, the holes are made to a spacing between 4m to 5m.
While digging the hoes depths, breakdown soil clods (big soil particles brought about during plowing) into fine particles to allow free movement of air and water through the soil.
Remove weeds and mix manure into the soil to expose microorganisms the soil to the sunlight to be killed.
After all these practices prepare and organize for the drip installation process. Collect drip irrigation equipment like drip tape, drip fittings (takeoffs, end caps and starters) and drip irrigation pipes as the main lines

Benefits of best drip irrigation for dragon fruit system

  1. The drip irrigation system is the most efficient method of irrigation. Through emitters, water is directly delivered to the plant root zone hence economical on water usage.
  2. In the best drip irrigation system, there is a constant benefit of water supply in small quantities to the plants. This creates an ideal moist condition for proper growth of most plants.
  3. The best drip irrigation system minimizes weed growth since water is only supplied to a particular crop root.
  4. The best drip irrigation system helps in the control of fungal diseases which grow very fast under moist conditions.
  5. Timeliness and labor-saving. In the best drip irrigation system, the control valves can be managed by one personnel. One person operates the whole system thus minimizing the labor costs. This minimizes production cost.
  6. Ease in fertilizer application. method of liquid fertilizer application (fertigation) is very easy and fast. Since water emitters are used to directly distribute fertilizers to particular crop/plants.

Basic Materials

The materials needed for the installation are just basic piping equipment. These materials include HDPE pipes, none return valves water filters, ball valves air release valves, elbows, ninety degrees tees forty-five degrees tees, Drip tapes, drip fittings, button drippers and any other relevant types of equipment

 

 

 

ORCHARDS DRIP IRRIGATION

ORCHARDS DRIP IRRIGATION FOR SALE IN KENYA

Orchard drip irrigation system for water melon for sale in Kenya
Orchard drip irrigation system for watermelon

Orchard drip irrigation system is the most efficient way to irrigate orchards since it can save water and nutrients by allowing water to drip slowly to the roots of the fruits plants, either above the soil surface or buried below the surface. Therefore, it is a more so efficient and effective method compared to overhead sprinklers and surface irrigation. Besides water efficiency, drip irrigation also reduces the risk of plant diseases that thrive in wet conditions.

Drip irrigation in Kenya is commonly used in an orchard because it minimizes the cost of production due to the larger spacing between the emitters and laterals. This also has some added advantages to the farmer in that it simplifies the irrigation procedure, thus minimizing distribution and evaporation losses. In addition, the system can be automated with a time clock and moisture sensors, and automated valves, thus maintaining optimal soil moisture with minimum labor.

Special features of the orchards plants that make drip irrigation possible.

Orchard drip irrigation is considered one of the best ways of irrigation an orchard because some of the orchards plants have various characteristics that are delicate when exposed to other irrigation methods.

  • The orchard’s plants are planted with a more considerable spacing difference between the rows and plants. This larger spacing is very easy to accommodate the drip irrigation method since They can efficiently distribute water per the individual plants.
  • Most orchards plants are adapted to any topography, be it flat land, rugged landscape, or even sloping lands; thus, drip irrigation is the best for this kind of plant.
  • All orchard plants require even water distribution at all times. Therefore, drip irrigation now becomes the only remedy for water solutions on such a farm.
  • The majority of these orchard plants have got a high rate of water absorption rate. Therefore, they can only solve this case by applying the drip method of irrigation.
  • These farms contain plants of single varieties that make it possible to be irrigated by a drip system.

Orchard plants can be irrigated using the drip irrigation method.

An orchard is a broad field spectrum that combines so many types and varieties of crops and plants. Some of these crops cannot survive under drip irrigation due to their unique features.

Example of orchard plants that can be watered by applying drip irrigation methods includes:

Vegetables

Cabbage,greenchillies,beetroots,brocoli,capsicum,carrots,cauliflower,cucumber,pumpkin,onion,peas,sweetpotatoe,tomato,etc.

Plantations

Areca nut, cashew nut, cocoa, coconut, oil palm, tea, coffee, mushroom, tomato tree, avocado, etc.

Fruits

Apple, banana, blueberry, chestnut, guava, mangoes, jackfruit, fig, papaya, passion fruit, pineapple, strawberry, water melon, almond tree, sweet oranges.

 

Factors to consider when designing irrigation system for an orchard.

When designing the drip system for avocado trees the following should be considered

  • Sustainability rate

The Ideal system should be capable of delivering water to a limited area under each tree when young to reduce water wastage.

  • Wetted diameter

System should be capable of increasing the wetted area to take into account tree growth and larger canopy area at orchard maturity. Sufficient pressure and pipe delivery must be catered for as the system has to expand.

  • Durability and flexibility

The drip system should not be prone to blockages.

  • High water delivery rate

The system should be capable of delivering more than 40 to 70 liters of water per hour per emitter .It should be designed in such a way that the cycle time between irrigations does not have to exceed one week. On well-drained soils, stress conditions can develop rapidly especially during periods of hot weather.

  • When to irrigate

The most efficient way to water is to apply water when it begins to show signs of stress from lack of water .These signs of water stress includes footprints or tire tracks that remain in the grass long after being made, many leaf blades folded in half, premature fruit drop and flaccid fruits on trees. The system should be designed in such a way that different blocks on different soil types, are capable of being irrigated as separate entities. This is important as water requirements can differ.

 

  • Efficiency of water application

An efficient watering does not saturate the soil, and does not allow water to run off. Therefore it is advisable to avoid extremes in watering frequency and amount. If you apply too much water, it runs off and is wasted. On the other hand, light frequent watering is inefficient and encourages shallow/restricted root systems.

 

Components of orchard drip irrigation system.

Orchards drip irrigation design components comprises of the following sections

Control head or pumping units

This comprises of valves, discharge, and pressure meters. It provides a means for Control and regulation of discharges, and pressures, including non-return valves and air vents. It also has an automation and control equipment, filters and dissolved fertilizer applicators.

The Main pipe

hdpe pipes for sale in Kenya
Eunidrip irrigation HDPE pipe

This is generally a rigid pipeline made from HDPE, asbestos cement or concrete. The main pipe is almost always buried and conveys water from the source to the main control points in the field.

The Sub-main pipe

This is a multi-valve pipe distributing irrigation water to the various sub-units within a unit. It is made up of rigid black polyethylene pipe which in most cases laid on the ground surface, with a diameter ranging between 32mm to 90mm “1.25” t” 3.5″),at a pressure  of 4 atm. When designing the sub main line it is good to consider several factors which include topography of the land, field geometry, water supply and the uniformity required.

The Manifold pipe

This is either a flexible (soft) or rigid pipe of high density polyethylene type, generally 20 to 75 mm diameter, which distributes water between the laterals belonging to a single sub-unit. The manifold and its lateral are designed and operated as a single unified system which is controlled by a single valve.

Lateral or Drip line pipe

This is basically a flexible (soft) polyethylene or PVC pipe buried or laid on the ground surface and which carries emitters or drippers.. Its diameter ranges from to 0.5 to 1- inch and the pressure rating about 4 atmospheres.

The Emitters or drippers

Button drippers for sale in Kenya
Button drippers

An emitter is a device or system element which makes the drip irrigation possible by providing irrigation water at low flows and atmospheric pressure. In Avocado drip irrigation design, the most suitable emitters used  are selected based on the following factors such as  low in cost, uniform in structure and operation ,simple to manufacture, and install, should be able to  maintain low problematic at standard operating pressure of between 3 to 30 m, and should be able to produce a constant low-rate water supply at varying line pressure change.

Other design components of avocado button drip irrigation include:

Water meter, reduced pressure backflow device, main valve, valve, flow meter gauges, air –vacuum relief valves, injecting equipment and filters.

 

Design layout of the orchard drip irrigation system.

To start the installation process, the following should be in place.

  • Tape measure, hose puncher to attach emitters to the pipes goof plugs to plug up any unwanted punch holes, metal stakes and zinc ties to secure the drip lines on their location.
  • Connect the water source to the main line delivery pipe using a water valve. Connect the two with a backflow preventer valve to stop contaminated water from leaking back into the initial water source.
  • Once the water source is connected to the main water distribution line, lay the laterals and delivery lines in accordance with the layout of your farm. Roll the tubing out around the garden beds, laying the line flush.
  • Once the mainline and laterals is in place, use a punch tool to make a hole in the lateral line wherever an emitter goes. Position your emitters so they are close to the root zone of each plant. To punch the holes, use boiling water or a hair dryer to heat the tube, which makes it softer to make holes. Once you have the tubing laid out and your emitter holes punched, secure the tubing into the ground with tubing stakes.
  • Once the system is completely installed, it needs to be tested by allowing water to flow in to the system.

Design layout of the orchards drip irrigation system continuation

  • Before allowing the water in to the system, ensure that all the valves are open. After main, sub mains and laterals are flushed completely close the flushed completely close the flush valve and end caps.
  • After closing of the valves and caps check the pressure at pressure gages and ensure that the pressure at the selected points is as per the design pressure.
  • It is also required to check the working of filters, air release valves and the fertigation unit. Once it is ensured that all the component is in good working conditions, then the operation should start.
  • Test the efficiency of water flow by turn on the water and allow it to run freely for a few minutes to flush out any dirt or debris. Once you see the system runs properly, close the tubing with an end cap.

Maintenance of orchards drip irrigation system.

For the water distribution in an orchard to perform effectively, proper maintenance should be done in various sections of the systems. This will also reduce the cost of production in terms of inputs and labor requirements to a farmer.

  • Emitters used should be able to match with the topographical status of the orchard farm. This should be checked regularly.
  • Orchards drip irrigation requires much spacing thus thinning should be done regularly in order to determine the quality of irrigation.
  • The distribution of the trees and crops should be in uniform state for efficient water use.
  • In an orchards with high drip irrigation demands alternative pipes should be factored.
  • When installing the orchard drip irrigation system, sub main line specifications should be considered.
  • This is to ensure maximum efficiency of drip irrigation systems. It also helps to protect the drip lines and drippers from early degradation by weather and chemicals.

Advantages of orchard drip irrigation system.

Orchards drip irrigation system has got various benefits to the farmer as follows.

  • Water is used and distributed at the optimum level.
  • Improves soil conditions.
  • Enhances food security to the farmer.
  • Allows reuse of waste water.
  • Fertilizer or nutrient loss is minimized during application..
  • Weeds effect are minimized since there is no water available for them
  • Drip irrigation enables the farmer to achieve maximum crop yield.
  • Fertilizers can be used with high efficiency.
  • Drip irrigation ensures minimum operating cost
  • There is no soil erosion as water is applied directly to plant roots.
  • Soil infiltration capacity is increased.
  • Fertilizers and ground water is not mixed.
  • improved seed germination is highly achieved.
  • We can use recycled water safely.
  • We can irrigate water in irregular shaped lands.
  • In this method of irrigation, energy cost is greatly reduced since it is operated in lower pressure.

Disadvantages of orchard drip irrigation system

Being that drip irrigation system is a very important tool to a farmer, it also possesses some few disadvantages.

  • Orchard drip irrigation is very expensive due to high initial cost to poor farmers thus not suitable for struggling farmers.
  • Clogging of drippers and emitter is a common thing in all drip irrigation systems. It may thus discourage most farmers to invest on this drip system of irrigation.

 

 

THE BEST DAM LINER PRICES IN KENYA

THE BEST DAM LINER PRICES IN KENYA.

Dam liner is thin water proof geomembrane that is used for the retention of liquids. It is used specifically in the lining of not only dams, fishponds, water reservoirs, garden ponds but also in hazardous and nonhazardous surface. They often offer simple ways of providing waterproofing and lining of water pans and ponds where the soil is too porous. Dam liners are also mostly applicable in the design of water harvesting structures used  in irrigation, drinking, and fish farming or any domestic purposes.

Characteristics of a good dam liner that a farmer may consider.

Dam liners have various characteristics that make them suitable to be used in various water projects and infrastructures. These characteristics vary depending on the type and dimensions based on the different manufactures. Furthermore, water projects structures including dams and ponds require the very best liner materials to prevent puncturing and leakage from the reservoir to increase their life span.

Dam liners should be able to last longer and have a span of about 25 years. It should be resistant to excess ultra violet radiation and UV treated in order to increase its durability, flexibility, and longevity depending on the thickness .

the liner should also be made from original materials so as to make it long-lasting since the virgin materials have not been affected by the weather elements.

Materials that are used to manufacture dam liners should be of high resistance to abrasion, puncturing, cracking, low temperature, corrosion, and should have a large temperature range.

They should be cheap, affordable, and friendly to the farmer, in terms of type of material, thickness, size of the dam among other features.

 

Types of dam liners sold in Kenya.

Majorly four types of dam liners are sold in the Kenyan market.

1.    Ethylene propylene diene monomer (EPDM) Liners

EPDM is a type of rubber dam liner that is mostly used in small and medium decorated ponds. It is very much flexible and easily bendable and can be bent into different shapes and corners. EPDM is very easy to puncture or tear with heavy, weighty, and difficult to pull abilities and it does not come into wide length. Its life expectancy can be about 20-30 years. This type of liner is thick enough that it can be challenging to fold the liner to fit into the pond’s cavity.

 

  1. Reinforced Polyethylene liners

Reinforced polyethylene liners are lighter in weight as compared to EPDM . They are one of the longest-lasting liners available in the current market, with a life span of up to 40 years, and are highly puncture resistant. They are stronger than other types of liners . They are higher and made with thicker material. The RPE liners are a good choice for large ponds because they are sold as large panels of approximately 60,000 square feet. The materials used to make them are cheap and cost-effective.

  1. Butyl polypropylene Liners (Hdpe liners).

These are box welded polypropylene synthetic rubber liners. The content in the material makes the material easy to fit into irregularly shaped ponds with many nooks and crannies. They are preformed and can be made into different shapes including 3-D shaped liners that are heat welded into rectangular and cylindrical shapes using flexible polypropylene liners. BPL is mainly used in informal ponds applications where clean liners are in demand. There is no need to fold them into different shapes. They have a life expectancy of approximately 25 years.

  1. Polyvinyl Chloride plastic liners(PVC Liners)

The Polyvinyl chloride liners are the most cheaper, durable, and flexible pond liners that are commonly used by most people in Kenya. They are readily available in the market stores in a variety of widths and thicknesses. These types of liners do not have ultraviolet protection therefore any portion of the liner is exposed to the sun.

 

Design specification of dam liners materials.

Most of dam liners are manufactured depending on the volume of water it is holds, thickness, solar intensity, length and the surface type. These factors depend on the various sizes of the gauge of the liners.

  • 300 microns (0.3mm) gauge

These types of liners are mainly used in smooth surfaces where there are no sharp objects. Severally used on small dams, with a specific length of 100meters and a width of up to 15meters. These liners are commonly welded together to fit the size of the dam. These make of liners have got a lifespan of approximately 10 to 20 years . They are ultraviolet treated thus can last longer. They are sold as black in color.

  • 500 microns (0.5mm) gauge

These liners are applied in light surfaces, where there are no sharp objects. Normally applicable in medium dams. Often sold at a length of 200meters and width of 6 or 8 meters. Apparently, it can be also welded together into different shapes and designs. Their lifespan ranges between 10 – 15 years. Are black in color? They are also ultraviolet treated to ensure a longer lifespan thus have chemical and light resistance.

  • 750microns (0.75 mm) gauge

The liners of these gauges are applicable for the medium to large projects. Usually sold in lengths of 150 meters and width 8 meters and are black in color. They can be welded and joined together into different shapes and designs. They are also ultraviolet treated thus longer lifespan of about 15-20 years.

  • 1000 microns (1mm) gauge

These are a type of dam liners of greater thickness. mostly applied in large projects with rough surfaces, rocky or stony. Commonly retailed at a specific length of 120 meters and width of 8 meters. Characterized with a longer life span of between 20 – 30 years. They are ultraviolet treated hence can last longer.

Preparation of the dam site for installation of dam liner.

There are certain preparations that must be done on the site where the dam liner is to be installed, before placing, unfolding, and installing the dam liner. Kindly ensure that:

  • The site is cleared and all roots, stumps logs, boulders, rocks, outcrops, all vegetation, organic matter, loose clods, surface debris, mud, waterlogged ground, and water are removed.
  • The surface is compacted by rollers or vibrators to a finished grade level.
  • The surface is leveled to a uniform texture not exceed that of graded aggregate.
  • The graded surfaces are sand blinded to a particle size not exceeding that of course sand to a thickness of 5 mm.
  • The geotextile  protection underlay should be placed to cushion and protect dam liner from damage by sharp objects as well as elevate puncture, impact, and abrasion resistance
  • Ensure that there is free drainage to all surfaces in contact with liner membrane, and the dam liner should not be installed in areas subject to flooding, tides, springs and thermal activity.

 

Installation procedure guide for dam liner.

 

  • Trench excavation. Dig or excavate a continuous perimeter trench on a stable berm all-round the dam site using a trench digger. The trench should be far enough from the edge of the berm to provide adequate anchorage. Backfill the trench at a height of 500mm over the buried liner.
  • Establishment of protrusions and venting. After establishing the trenches, dam liner penetrations should be subjected to designed requirements for easy operational purposes. The approved foundations, footings, pads, should be installed to allow for better stability at penetration positions. The sealing of the protruded structural or service elements to the liner membrane should be provided by an appropriate means to minimize liner stress.
  • Lay the unpacked liner at position on berm level ground and unroll to its full length at pond perimeter.
  • Then make the lower liner loose edge into the perimeter anchor trench allowing ample material to be secured to the full width and depth.
  • Using temporary sandbags hold the dam liner edge down intermittently along the trench at its anchor position.

Installation procedure guide for dam liner continuation

  • Depending on the stability of the trench wall, the material should be carried across the lining area by two separate installation crews each carrying half the total weight of the liner. Extend the liner from its folded end to the opposite perimeter trench while allowing ample liner to relax into its final position.
  • By pulling or tugging at the liner after it has settled on the pond/dam bed as friction against the ground of a large liner area can be difficult to overcome. This can only be avoided by taking proper precaution before beginning the installation process.
  • Finally, before the end of installation notes that when the liner has been loose laid with evenly distributed surface ripple, place all surplus liner material into the perimeter anchor trench, allowing ample liner on the pond/dam bed to avoid stretching from the ground settlement after filling.

 

Problems associated with the leakage of a dam liner.

Dam liners are faced with various challenges that may make them to crack and begin leaking. Some of these challenges may be environmental caused or human caused .They includes:

  • Poor choice of construction materials.
  • The internal soil erosion or piping
  • The cracking of the liner caused by changes to water levels
  • The presence topsoil and vegetation at the embankment site
  • Presence of an unsuitable soil type in the dam wall
  • The absence of a cut-off trench
  • Presence of uncompact soils techniques.
  • The presence of rock and gravel at the basement of the liner.
  • Presence of sand in the storage basin
  • The damage caused by animals and insects.
  • Presence of slumping cracks along the length of the wall due to a combination of poor compaction, excessive seepage and excessive steepness of bank
  • Poor site location for the dam installation.
  • Failure of dam liner due to longer lifespan.
  • Presence of trees on dam bank thus causing loss of storage volume due to uptake for self-watering.

Advantages of a dam liner to the farmer.

  • Most of dam liners are resistance to chemicals especially High-density polyethylene liners, thus there is no threat for hazardous waste.
  • Dam liners have low-permeability rate hence can retain water for many years.
  • They are safe and secure from water penetrations, and also it resists rainwater to seep into the dam liners.
  • They are ultraviolet-resistant and therefore are not easily damaged by environmental stress.
  • Most dam liners are cost-effective hence can easily be afforded by many poor farmers.
  • Available in a variety of shapes and sizes
  • Very easy to seal.
  • Usually light in weight hence easy to carry.
  • Are easily customized according to the purpose they portray.
  • Easy to clean and maintain.
  • Most of dam liners are highly durable and flexible.
  • Can mostly be designed into any required shape depending on the nature of the dam.
  • relatively  easy and very fast to install.

Disadvantages of a dam liner to the farmer.

Dam liners have got various limitations to the farmers, especially to the poor small scale farmers .This is due to expensive cost of maintenance and installation and the nature of the dam liners.

  • Some of the dam liners are hard to conceal thus becomes deteriorated faster.
  • They are manufactured and sold with limited shapes and sizes so the farmer’s preferences cannot be satisfied.
  • Most of these dam liners are costly in terms of cost, maintenance and transportation and hence most farmers are unable to afford them.
  • They are hard to design especially for marshland and borderline plants.