The Low Erosivity Waiver (LEW) or the Rainfall Erosivity Factor Calculator for Small Construction Sites app is a responsive, map-centric, mobile ready web application that allows end-users (i.e. construction companies, NPDES permitting authorities) to determine if they can waive NPDES permitting requirements for stormwater discharges from small construction sites. The waiver is possible if
- the construction site disturbs less than five acres, and
- the rainfall erosivity factor (“R” in the revised universal soil loss equation, or RUSLE) value is less than five during the period of construction activity.
As such, LEW provides a web application and associated web service that allows an end-user to provide information about their construction activities to retrieve an “R” factor ranking to determine if a waiver is appropriate.
- Local Development Environment Setup, instructions for getting the application running on your device to support coding.
- How to contribute to the project, learn how to help improve the application.
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