How to Calculate Geomembrane Quantity for a Pond

Geomembrane is a plastic liner, often called HDPE tarpaulin, commonly used to line aquaculture ponds, water storage ponds, artificial lakes, landfill projects, biogas covers and more. Before you calculate geomembrane quantity, note that it comes in several thicknesses: 0.3 mm, 0.5 mm, 0.75 mm, 1 mm, 1.5 mm and 2 mm. Let’s take a shrimp pond as an example. Shrimp ponds generally use 0.5 mm geomembrane.

In a shrimp pond, geomembrane maintains water quality by keeping it from mixing with soil, mud, grass and similar material from the pond bottom, and prevents erosion on the pond slopes. This is a great help in keeping water quality stable throughout the farming cycle.

Most pond farmers do not yet know how to calculate how much geomembrane their pond needs. Here we explain how to work out the geomembrane quantity for your pond.

• First, find the area of your pond. If your pond measures 50 m x 70 m, its area is 3,500 m². With a depth of 1.5 metres, add 30% to the pond area, giving 4,550 m².

The 30% compensates for the pond walls, because the walls must also be lined with geomembrane.

• Second, find the area of geomembrane per roll by multiplying its length by its width. A 0.5 mm geomembrane roll is 5.8 m wide and 50 m long, so the area of one 0.5 mm roll is 290 m².

To find the number of rolls your pond needs, divide the pond area + 30% by the geomembrane area per roll.

So the geomembrane needed for a 3,500 m² pond (50 m x 70 m) that is 1.5 m deep is 15.68 rolls, rounded up to 16 rolls.