Client: Clark County Public Works, Vancouver, WA
Clark County contracted with Otak to update the County's stormwater ordinance. Clear Creek Solutions was hired to produce HSPF calibrations of two watersheds in the county.
The calibrated HSPF parameter values were then used to update the Western Washington Hydrology Model (WWHM) for Clark County.
In order to use HSPF as the hydrologic stormwater engine for WWHM, it must be calibrated to watersheds that reflect the range of climatic, topographic, soil, and land use conditions within Clark County.
Process and Solution
In this study, model simulations were performed for the Mill Creek and Gee Creek watersheds.
Topographic, soils, and land use/cover information was used to develop the model segmentation and parameter inputs for the watershed models.
Both quantitative and qualitative comparisons were performed to support the model performance evaluation effort.