Whipple Creek Watershed Assessment


As a requirement of the State of Washington NPDES Phase I Municipal Stormwater Permit (2013-2018), Clark County is required to create a watershed-scale stormwater plan. The plan's goal is to identify a stormwater management strategy(ies) that would result in hydrologic and water quality conditions that fully support 'existing uses' and 'designated uses' (per WAC 173-201A-602) throughout the stream system.

Watershed Assessment Plan Report

Clark County Whipple Creek Watershed-Scale Stormwater Plan Report (September 2017)

Clark County Whipple Creek Watershed-Scale Stormwater Plan Appendices (September 2017):

Whipple Creek location

The Whipple Creek watershed is located in western Clark County, draining west from the low hills just east of I-5 (from approximately NE 144th St. to NE 194th St. and NE 29th Ave.) to the Lake River. The 12.1 square mile watershed is part of the West Slope main watershed that makes up NW Clark County. The upper sub-watershed is 8.8 square miles and includes approximately 4.4 square miles inside the Vancouver urban growth boundary. The lower sub-watershed is 3.3 square miles and is mostly rural. Below is the current 2014 map of the watershed:



Whipple Creek history

The Whipple Creek watershed was once dominated by rural and agricultural uses, as well as forested riparian corridors. Clearing has occurred overtime to make way for farming, agricultural uses, housing and commercial development. The image below shows the land holdings in the 1886 Donation Land Claim document for T3NR1W.


The 1955 aerial photograph shows the extent of forest cover as well as the agricultural farm properties throughout the watershed.