Coronado-Fremont Stormwater Improvements

Project Overview

This project located in the Geneva neighborhood, targets treatment of stormwater flows draining to Lake Whatcom from over 170 acres of residential development and forested area. Water quality was degraded in this part of the watershed from high phosphorus loading and fecal coliform bacteria levels. Localized flooding was also common due to increased stormwater runoff and greater peak flows from increased development. As a result, substantial streambank erosion and deep channel incisions were occurring in Coronado Creek running to Lake Whatcom

The Coronado-Fremont project includes a series of improvements, including:

Installation of bio-infiltration swales with phosphorus adsorbing media along Beecher Avenue between Fremont Street and Whitney Street.
Improvement of an eroded creek channel to a more naturally functioning state to decrease creek velocities, reduce erosion, and thereby reduce phosphorus loading into the lake.
Replacement of undersized and compromised culverts.
Installation of rock weir check dams along Fremont Street.
Installation of hydrodynamic sediment separators.
Installation of cartridge Phosphosorb filter vaults.

This project was completed below budget in mid October 2014. The Coronado-Fremont Stormwater Improvement Project is the third major sub-basin improvement in the Geneva neighborhood. Part of the funding for this project came from a Stormwater Retrofit and Low-Impact Development Grant from the Washington State Department of Ecology.