Dedicated to advancing the use of fabricated geomembranes through education, research, and technology transfer.

Factory fabrication reduces field welding, reduces installation time and costs, allows modular construction and provides consistent seam and liner quality.


The FGI Pond Leakage Calculator is an excel spread sheet based on Darcy's Law and produces a comparison between leakage rates for compacted soils and synthetic liners.  The FGI calculator allows the user to input the size of the containment basin (including length, width, depth, side slope angle and freeboard), the anticipated level of permeability using compacted clay/soil, and the relative cost of an acre foot of water.  It will in turn provide the volume of the basin in gallons, a comparison of leakage rates between the compacted soil layer and a synthetic membrane both in gallons and dollars. 

This tool is designed to help consultants, engineers, architects and end users best decide how to line basins for capture and/or protection.  It does not take into account variances in quality of either liner type, construction short falls or operational impact on the long term effectiveness of the chosen liner.  FGI has additional research and publications to help with these other aspects of successful liner implementation.

Pond leakage calculator documents
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The FGI Panel Weight Calculator is a spreadsheet that calculates the surface area of a containment basin and then the number of factory fabricated geomembrane panels that are required to cover or line the bottom of the basin. Afterwards, the spreadsheet calculates the weight of each panel based on the type of geomembrane selected, which can be varied. Using the number of panels required, the number of truck loads and days for field installation are calculated based on user selected allowable shipping weight/truck and number of panels that can be installed/day. The Calculator allows the user to input and vary the size of the containment basin, including length, width, depth, side slope angle, and freeboard. Using this data, the spreadsheet calculates the volume of the basin in gallons or liters and the surface area required to be covered or lined.

Panel Weight calculator documents
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