Leachate Generation from a Water Balance

Turns precipitation, runoff, and evapotranspiration into leachate per year, per day, and per open acre.

Run the calculator

Example

You enter

Open cell area (acres) 20
Annual precipitation (in) 40
Runoff coefficient 0.15
Evapotranspiration coefficient 0.3
Capped-area infiltration (in/yr) 2
Design storm depth (in) 2

You get

Infiltration 22.0 in/yr over 871200 sq ft
Leachate generated 11947887 gal/yr (32734 gpd)
Leachate (GPD) 32733.9
Per open acre 1636.7
Capped, same area 1086172 gal/yr (2976 gpd) -- 91% less
Capped (GPD) 2975.81
Capping reduction (%) 90.9091
The design storm 597394
Storm days of average 18.25

Details, formula, and sources

Against the same area capped and against a design storm. The worked 20 acre cell makes 1,637 gpd per open acre and 91% less once capped; one storm delivers 18 days of average flow.

infiltration = precipitation x (1 - runoff coefficient - evapotranspiration coefficient); leachate volume = infiltration depth x area, at 7.48 gallons per cubic foot.

A screening water balance. HELP modelling, the site's own leachate records, and the permit's storage and treatment requirements govern.

Public arithmetic; HELP is published by the EPA and is freely available.

Estimate. AHJ and licensed professional govern.

Field names used by the API: open_acres, annual_precip_in, runoff_coefficient, evapotranspiration_coefficient, capped_infiltration_in_per_year, design_storm_in, infiltration_in_per_year, leachate_gal_per_year, leachate_gpd, gpd_per_acre, capped_gal_per_year, capped_gpd, capping_reduction_pct, storm_volume_gal, storm_days_of_average

Coefficients entered; runoff and evapotranspiration are site and cover specificsite records / HELP
Scope infiltration only; it does not model the liner, the collection system, or recirculationspec-v1791 scope