Pond Liners to Save Water and Ease Maintenance

Preserving Water, Pond Liners for Sustainable Fish Farming.

Pond liners, made of materials like PVC or polyethylene, act as synthetic geomembranes, preserving water, enhancing biosecurity, and simplifying pond maintenance. They are adaptable to various pond sizes and shapes, with plastic liners being robust but slightly harder to install in smaller ponds.

This technology is TAAT1 validated.

8•9

Scaling readiness: idea maturity 8/9; level of use 9/9

Cost: $$$ 500 USD

a 15m x 10m x 1m pond.

ROI: $$$ 50 %

reduction in water-related costs

2 - 3.5 USD/square meter

Sheet plastic

IP

Open source / open access

Problem

Water seepage leads to significant water loss, especially in ponds constructed on porous soils like sands and silts.
Evaporation from ponds, particularly in areas with high temperatures, results in additional water loss, affecting water availability for fish farming.
Algal blooms caused by excessive nutrient levels in ponds can lead to water quality issues, impacting fish health and productivity.
Without pond liners, nutrient cycling between water and sediment may be inefficient, affecting pond ecosystem balance and requiring more intensive maintenance.
Sandy soils and areas with poor access to freshwater are particularly prone to water loss in ponds, exacerbating water scarcity challenges for fish farmers.

Solution

Reduces water losses through seepage by creating an impermeable barrier between the water and the soil.
Decreases water evaporation from ponds, helping to preserve the available water quantity.
Prevents the formation of algal blooms by limiting excessive nutrient input into the water.
Promotes nutrient cycling between water and sediment, thereby improving overall pond health.
Offers a practical and sustainable solution for building ponds in porous soils or regions with limited access to freshwater.

Key points to design your business plan

This technology reduces water seepage and evaporation, conserving resources and lowering costs in aquaculture. It promotes responsible water management, maintains optimal water levels for fish, and prevents contamination. Additionally, it helps mitigate climate change impacts by conserving water and reducing emissions.

Choose the right equipment size, keeping in mind variable investment costs; small-scale soil leveling systems start at 4,700 to 5,500 USD, and water lifting tools range from 30 to 1,000 USD.
Consider delivery costs, import duties, and taxes for locations like Kenya and Nigeria.
Identify context-specific land leveling and water lifting methods.

When selecting equipment, consider varying investment costs:

Cost of sheet plastic: Approximately USD 2 per square meter for a thickness of 0.5 mm, increasing to USD 3.50 for a thickness of 1 mm.
Cost of plastic liner with sealing and installation for a pond: Around USD 500 for a pond measuring 15 m long, 10 m wide, and 1 m deep.
Rubber sheet lining can decrease water loss through seepage and evaporation by up to 50%.
Comparative analysis of 700 fish farmers in south-western Nigeria showed that ponds with plastic liners yield significantly greater net profits compared to unsealed earthen ponds.

Collaborate with aquaculture organizations or stakeholders for effective implementation of these technologies within your country or region.

Adults 18 and over: Positive high

Under 18: Positive high

Women: Positive medium

Climate adaptability: Highly adaptable

Farmer climate change readiness: Significant improvement

Biodiversity: Positive impact on biodiversity

Carbon footprint: A bit less carbon released

Environmental health: Moderately improves environmental health

Soil quality: Does not affect soil health and fertility

Water use: A bit less water used

Countries with a green colour: Tested & adopted
Countries with a bright green colour: Adopted
Countries with a yellow colour: Tested
Countries with a blue colour: Testing ongoing

Countries where the technology is being tested or has been tested and adopted
Country	Testing ongoing	Tested	Adopted
Benin	–No ongoing testing	–Not tested	Adopted
Côte d’Ivoire	–No ongoing testing	–Not tested	Adopted
Democratic Republic of the Congo	–No ongoing testing	–Not tested	Adopted
Ethiopia	–No ongoing testing	–Not tested	Adopted
Ghana	–No ongoing testing	–Not tested	Adopted
Kenya	–No ongoing testing	–Not tested	Adopted
Malawi	–No ongoing testing	–Not tested	Adopted
Mali	–No ongoing testing	–Not tested	Adopted
Niger	–No ongoing testing	–Not tested	Adopted
Nigeria	–No ongoing testing	–Not tested	Adopted
Rwanda	–No ongoing testing	–Not tested	Adopted
Senegal	–No ongoing testing	–Not tested	Adopted
Sierra Leone	–No ongoing testing	–Not tested	Adopted
South Sudan	–No ongoing testing	–Not tested	Adopted
Sudan	–No ongoing testing	–Not tested	Adopted
Tanzania	–No ongoing testing	–Not tested	Adopted
Togo	–No ongoing testing	–Not tested	Adopted
Uganda	–No ongoing testing	–Not tested	Adopted
Zimbabwe	–No ongoing testing	–Not tested	Adopted

This technology can be used in the colored agro-ecological zones. Any zones shown in white are not suitable for this technology.

Agro-ecological zones where this technology can be used
AEZ	Subtropic - warm	Subtropic - cool	Tropic - warm	Tropic - cool
Arid
Semiarid
Subhumid
Humid

Source: HarvestChoice/IFPRI 2009

The United Nations Sustainable Development Goals that are applicable to this technology.

Goal 6: clean water and sanitation

Goal 12: responsible production and consumption

Measure Pond Dimensions:
- Calculate pond volume using the formula: Volume = (d/6) x (At + Ab + 4 Am).
- Where V is volume, d is depth, At is the area on top, Ab is the area at the bottom, and Am is the area at half the depth.
Prepare Liner Installation:
- Clean a 25 cm strip along both edges of the liner with rubbing alcohol.
- Apply primer in a 15 cm strip along the top of one liner piece.
Seaming Two Sheets:
- Glue the two sheets with double-sided tape.
- For polyethylene, heat-seal the sheets.
Ensure Watertight Seals:
- Overlap sheets with an extra 50 cm.
- Remove shoes when stepping on the liner to prevent damage.
- During water filling, pull and tuck the liner into shape for a neat finish.
Adhesive Application:
- Clean strips with rubbing alcohol for proper adhesion.
- Use primer and glue to bond sheets securely.
Calculation for Additional Material:
- Add an extra 50 cm where sheets overlap for watertight seals.