Project Snapshot

In a district where a single dry monsoon can decide the fate of a farming season, water saved is a livelihood protected. When a water storage structure at Amreli, Gujarat, needed to hold its stored volume reliably through a hot, water-scarce climate without losing it to the ground below, the design team chose an engineered geomembrane over a traditional earthen or masonry lining. Ocean Non Wovens supplied 3,600 square metres of Ocean HDPE Liner for the containment works. This case study explains why that was the right technical choice, how it performed, and what the wider industry can take from it.

Why Geosynthetics Now Anchor Water Storage

Saurashtra is a region defined by its relationship with water. Rainfall is erratic, groundwater is over-drawn, and the difference between a full storage pond and an empty one is often the difference between a good farming year and a ruined one. For generations the answer to holding that water was compacted earth or masonry, but both share a fatal flaw: they leak. An earth-lined pond can lose a large share of its stored water to seepage, quietly draining away the very resource it was built to protect.

Geosynthetics changed that equation. A polymeric geomembrane presents a continuous, effectively impermeable barrier engineered to a known performance and installed quickly over almost any prepared surface. The International Geosynthetics Society (IGS) has long documented how geomembranes outperform mineral liners in seepage control and constructability, and bodies such as the Bureau of Indian Standards (BIS) and the Central Board of Irrigation and Power (CBIP) now publish detailed guidance for their use in water works. For a water-stressed district like Amreli, that reliability is the whole point.

What Ocean HDPE Liner Is and How It Works

An HDPE liner, or geomembrane, is a continuous sheet of high-density polyethylene manufactured to a controlled thickness and used as an impermeable barrier. Its purpose is not to carry load or confine soil, but simply to stop water passing through. The tightly packed polymer chains give the sheet a permeability so low that water cannot move through an intact panel. On site, panels are fused together with heat, usually by hot-wedge welding, so every seam is as watertight as the parent sheet, turning many separate rolls into a single, monolithic membrane lining the structure.

The governing principle is impermeable containment. Where an earthen bund relies on the slow, imperfect resistance of compacted soil, the geomembrane presents a positive physical barrier that holds the water where it belongs. Material properties and test methods for these sheets are governed internationally by GRI-GM13 from the Geosynthetic Institute (GSI) and in India by IS 16352:2020 from BIS, the standard written specifically for HDPE lining geomembranes.

Why the HDPE Liner Was Chosen Over Conventional Methods

The traditional alternatives each carried a penalty that did not suit the Amreli site. A compacted earthen lining would have needed large quantities of low-permeability soil, not always available locally, and even when well built it continues to seep. A concrete or masonry lining is durable but brittle; under the ground movement and thermal swings of a semi-arid climate it cracks at joints, and every crack becomes a leak that is hard to trace and costly to repair.

The geomembrane offered a cleaner answer. A thin, flexible, genuinely impermeable sheet eliminated the seepage problem outright while adding almost no dead weight to the ground. It installed far faster than a poured lining, flexed with minor settlement instead of cracking, and required only a fraction of the imported material. This shift, where an engineered membrane replaces bulk mineral construction while improving performance, is exactly what modern CBIP and BIS guidance now encourages.

The Engineering Challenges at Amreli

A water storage structure in this setting concentrates several difficult problems. The subgrade needed careful handling, since any stone or sharp fill left in the formation could puncture the sheet once the water load pressed down. Seepage and water loss were the central threat the project existed to defeat, because in a water-scarce district every litre lost to the ground is a litre that will not reach a field. High summer temperatures and strong sunlight demanded a liner that would not degrade on exposure, and because groundwater and trapped gas can push upward when a pond is drawn down, uplift had to be accommodated. The side slopes were exposed to erosion and wave action, the basin needed anchoring and gas venting beneath the liner, and, as with most rural water works timed around the monsoon, the job had to be finished to a tight programme without compromising watertightness.

How Ocean HDPE Liner Performed

The liner delivered exactly the behaviour the site needed. Its defining contribution was seepage control: by presenting a continuous impermeable barrier, it stopped the downward loss of stored water almost entirely, turning what could have been a leaky basin into a dependable store of irrigation water.

On the embankments it provided slope protection and erosion control, holding the face against wave action and scour where an unlined slope would wash away. Being flexible, it accommodated settlement by stretching rather than cracking, and its inherent chemical resistance let it tolerate the stored water chemistry and dissolved salts without degrading. The net effect was reliable water conservation, the true deliverable of any storage project in Saurashtra.

The Technical Picture

Three mechanisms explain the performance. The first is impermeability: the density and crystallinity of HDPE give a hydraulic conductivity so low that seepage through an intact sheet is negligible. The second is hydrostatic containment, where the correctly anchored membrane resists the pressure of the stored water column without displacement. The third is strain accommodation: because the sheet elongates significantly before failure, it absorbs settlement and thermal movement by stretching rather than tearing. Correct thickness selection balances puncture resistance against flexibility, and tested welds turn many panels into one continuous barrier.

The Site Realities Few Companies Discuss Openly

A geomembrane is only as good as its installation, and this is where projects quietly succeed or fail. Proper subgrade preparation, meaning a smooth, compacted, stone-free surface, is non-negotiable, because one sharp protrusion can puncture the sheet under load. A well-formed anchor trench around the perimeter locks the liner in place and stops it slipping or lifting. Panel deployment and seaming must be disciplined, with sheets positioned to minimise field joints and welded under controlled temperature. Wind is a real enemy on open water works, so ballast matters until the liner is secured, and thermal expansion in the Gujarat heat leaves deliberate slack that must be managed so the sheet does not go into tension when it cools. Attention to gas venting, correct sequencing, and rigorous inspection of every weld separate a watertight pond from a leaky one. Seams are proven with air-pressure and vacuum-box testing, in line with GRI and IS practice. The most common industry mistakes, namely poor subgrade preparation, weak weld control, and skipped seam testing, were specifically guarded against here.

Long-Term Performance and Lifecycle Value

Water storage assets are judged over decades, so durability is central. Ocean’s HDPE resin is stabilised with carbon black for strong UV resistance, which matters greatly under the intense Saurashtra sun. It is engineered for high environmental stress-crack resistance, verified through notched constant-tensile-load testing to ASTM D5397, so the sheet resists the slow crack growth that ends the life of lesser polyethylenes. Its chemical resistance shrugs off the salts and soil chemistry a water body is exposed to, while its tensile behaviour to ASTM D6693 confirms performance under the cyclic wet-dry and thermal loading a pond sees year-round. Maintenance stays low, and the combination of thin section, fast installation and long service life delivers substantial lifecycle cost savings.

Sustainability Built Into the Design

The environmental case reinforces the engineering one. By preventing seepage, the liner directly conserves water, which in a district like Amreli is the single most valuable outcome of the project. Replacing bulk clay or concrete with a thin membrane sharply cut the material required, lowering both the carbon footprint and the transportation needed to haul heavy mineral construction to a rural site. Faster placement shortened the construction window, and the long service life means fewer rehabilitation cycles. This alignment of water saving, durability and resource efficiency is exactly what BIS and CBIP guidance increasingly encourage for agricultural water infrastructure.

Beyond Water Storage: Where HDPE Liners Deliver

The same containment technology that sealed Amreli is proven across a wide span of works. HDPE geomembranes line reservoirs and farm ponds, seal canals against seepage, form the barrier layers of landfills and tailings ponds, hold water in aquaculture and rainwater harvesting systems, contain flows in sewage and effluent treatment plants and biogas digesters, and waterproof decorative lakes and check dams. Wherever liquid must be kept in, or contamination kept out, an engineered geomembrane beats mineral lining on speed, weight and reliability.

Partner With Ocean Non Wovens

The Amreli Water Storage Project reflects what Ocean Non Wovens does best: engineering-grade geosynthetics, manufactured to international and Indian specification and delivered on the timelines that real projects demand. As a leading Indian manufacturer and supplier of HDPE liners, geomembranes, geocells, geotextiles and allied geosynthetics, Ocean Non Wovens supports water resources and environmental engineering, agriculture, defence infrastructure, highways, railways and large-scale industrial developments across the country. If your project involves seepage control, water storage, weak ground or a tight programme, our technical team can help you specify and supply the right solution at scale. Talk to Ocean Non Wovens: geosynthetics engineered to hold India’s most precious resource.