Donald Ave Water Quality Retrofit

Project Overview: EV171

This project will improve water quality in Lake Whatcom by retrofitting an existing stormwater treatment facility on Northshore Drive near Donald Avenue. Work along Northshore Drive and Donald Avenue east of Northshore is expected. This site is located adjacent to a two-lane road without an easy detour. Work will be planned to minimize impacts to roadway users during construction.

Lake Whatcom currently has a Total Maximum Daily Load (TMDL) plan for total phosphorus and bacteria. The primary water quality concern in Lake Whatcom is low dissolved oxygen (DO) due to increased levels of phosphorous and fecal coliform bacteria that enter the lake through stormwater runoff. This project is identified as a priority project in the City’s Lake Whatcom Retrofit Plan in accordance with the Lake Whatcom TMDL Implementation Plan that addresses phosphorus and bacteria pollution.

This project will retrofit an existing City-owned stormwater facility with treatment and infiltration systems designed to maximize phosphorus removal. The project is expected to replace the existing 7,250 square foot sand filter with a City of Bellingham Phosphorus Optimized Stormwater Treatment (POST) System. The POST System was certified in February 2022 by the Washington Department of Ecology’s emerging stormwater treatment technology program (TAPE Program) and approved with General Use Level Designation for Basic (TSS) and Phosphorous Treatment.

This project will treat runoff from 27 acres of residential development which currently adds about 24 pounds of phosphorus to the lake annually. If POST media is used, the system is expected to remove approximately 21 pounds of phosphorus annually and reduce total suspended solids (TSS) and dissolved copper and zinc.


The project was awarded a grant by the Department of Ecology (DOE). The project design and construction phases are funded with State funds (75%) and local funds (25%) through this DOE grant which expires June 30, 2025.

Status – February 2023

Accomplishments: Contract for professional services with Pacific Survey & Engineering executed. Site survey and geotechnical exploration was completed. Site specific inflow data collection is currently ongoing. 30% Design Plans complete.

Next Milestones: Design Report with 60% Plans.

Project Details


Jessica J. Bennett, PE
Phone: (360) 778-7923

Participating Departments

Affected Neighborhoods

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