Western Washington Hydrology Model (WWHM)

This dataset includes versions of the WWHM as they are released, including installation files and descriptions of changes along with dates and version numbers. WWHM2012 is still the official program to be used by permittees for compliance with MS4 Permits. WWHM2025 is a test/Beta version.
Organization: State of Washington
Organization URL: https://catalog.data.gov/organization/washington
Last updated: 2026-05-05
Tags: ecology, hydrology, model, ms4, western washington hydrology model, wwhm