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 caclulator 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.