HDPE Liner for Township Infrastructure

Khopoli, Maharashtra

Project overview

Project Name: TATA Township Project

Client: Shivraj Construction

Location: Khopoli, Maharashtra

Products Used: Ocean HDPE Liner, 1 MM (1000 micron); Ocean HDPE Geocell 330 x 100 mm; Ocean Non Wovens Geotextile 1.8 mm

Quantity: 9,400 SQM of HDPE liner; 7,250 sq m of geocell; 9,400 sq m of geotextile

Ocean Non Wovens supplied 9,400 SQM of Ocean HDPE Liner (1 MM) to the TATA Township Project at Khopoli. The liner was used as a geomembrane barrier for water containment, drainage control and subgrade protection, keeping water in the structures meant to hold it and out of the ground and services around them. The same order included 7,250 sq m of Ocean HDPE Geocell 330 x 100 mm and 9,400 sq m of Ocean Non Wovens Geotextile 1.8 mm.

Khopoli sits at the foot of the Western Ghats in Raigad district and gets heavy south-west monsoon rain. On a township site that means large volumes of stormwater to collect, store and route, on ground that stays wet for months.

Where HDPE liners are used in a township

An HDPE geomembrane is a continuous, very low-permeability sheet with good tensile strength and chemical resistance. In township infrastructure it typically serves as a containment or protection layer in:

• Water reservoir lining: stops seepage losses from stored water.
• Stormwater drainage channels: keeps flow in the channel and stops it eroding or saturating the soil around it.
• Utility corridors: keeps moisture and contaminated water away from underground services.
• Artificial ponds and landscape water features: holds water so ponds keep their level without constant top-up.

Other geosynthetics usually work alongside the liner on a township: geotextiles and geogrids to stabilise weak subgrade under internal roads, geocomposites for subsurface drainage behind walls and under landscaped areas, and cushion geotextiles under the liner itself.

Geocell and geotextile on the same project

Ocean Non Wovens Geotextile 1.8 mm (9,400 sq m): the geotextile quantity matches the liner area. A needle-punched non woven of this thickness is the usual cushion layer for an HDPE liner: placed beneath the sheet, it spreads point loads from stones in the subgrade, and placed above it, it protects the liner from cover soil and construction traffic. It also lets water or air beneath the liner move to a vent or drain instead of pushing the sheet up.

Ocean HDPE Geocell 330 x 100 mm (7,250 sq m): geocell is a honeycomb of welded HDPE strips (330 mm weld spacing, 100 mm cell depth) that is stretched open on site and filled with soil, aggregate or concrete. On a township in heavy monsoon country it is typically used in two ways. On embankment and channel slopes, the cells hold topsoil or stone against runoff while vegetation establishes, and a lined slope can be covered this way so the cover does not slide off the geomembrane. Under internal roads, parking and paths, the confined infill forms a stiff layer that spreads wheel loads over a soft subgrade. The infill and anchoring are chosen to suit the slope and the use.

Site challenges

• Construction constraints: limited working space, several utilities going in at once, and civil, mechanical and electrical works to coordinate. Liner work has to be sequenced so other trades do not damage it.
• Water management: stormwater has to be collected and routed without waterlogging, which otherwise damages structures and makes areas unusable.
• Variable subgrade: mixed soil profiles, compacted and uncompacted layers and the risk of differential settlement. A flexible HDPE sheet can follow modest settlement where a rigid lining would crack.

Installation and quality control

An HDPE liner performs only as well as it is installed. The usual sequence:

1. Subgrade preparation: remove sharp objects and debris, compact to a smooth surface and form the slopes needed for drainage.
2. Protection layer: lay a cushioning geotextile where the subgrade is stony or the cover material is coarse.
3. Liner deployment: unroll panels along the design contours, avoid dragging, and leave slack for thermal expansion and contraction.
4. Seaming: join panels by hot-wedge welding, with extrusion welding at patches and details, then test seams non-destructively (air pressure on double-wedge seams, vacuum box on extrusion welds).
5. Anchoring and cover: fix the edges in an anchor trench and place any cover or overlay material carefully so equipment never runs directly on the sheet.

A single bad weld or puncture can undo the whole barrier, so continuous inspection during installation matters more than any property on the datasheet.

Long-term performance

• Low permeability: prevents water loss and keeps contaminated runoff out of the soil.
• Tensile strength: takes stresses from overlying loads and minor settlement.
• Chemical resistance: suitable for wastewater and urban runoff.
• UV and thermal stability: carbon-black stabilised HDPE tolerates sun exposure and temperature swings, though covered liners last longest.

With less seepage damage to repair, a lined system generally needs less maintenance over its life than an unlined or rigid one.

About Ocean Non Wovens

Ocean Non Wovens supplies geosynthetics to infrastructure projects across India, from highways in difficult terrain to industrial facilities and township developments such as this one at Khopoli. For liner selection on your project, see our pond liners or geosynthetics pages, or contact the Ocean team.