Water Quality Improvement Project
Oakland Bay and Hammersley Inlet:
Fecal Coliform


Oakland Bay and Hammersley Inlet are located in Mason County, Washington. Together they form a long, backwards hook that extends westward from Puget Sound. The city of Shelton is located at the elbow of the hook.

Oakland Bay and Hammersley Inlet are typical of the narrow, shallow embayments characterizing South Puget Sound. While they are highly productive areas for shellfish and salmonids, low flushing rates also make these areas very sensitive to human impacts. For over 100 years Oakland Bay’s protected waters have made it an ideal port for the city of Shelton, whose economy is based upon the lumber and pulp mills dominating the waterfront. Shelton operates a domestic wastewater treatment plant that discharges treated sewage into Oakland Bay near Eagle Point.

Oakland Bay is one of the most important commercial shellfish areas in the country, producing over three million pounds of manila clams a year. Other shellfish produced in this area include Kumamoto and Pacific oysters, and mussels. The shellfish industry is a critical economic factor to the local economy. Oakland Bay has numerous commercial shellfish growers registered with the Washington State Department of Health. There are hundreds of recreational harvesting areas on state-owned tidelands and it is an important harvest area for the Squaxin Island Tribe.

Land use is primarily commercial forest, with a much smaller percentage dedicated to residential development and agriculture. Shorelines of both the marine area and the lakes in the watershed are heavily developed. Agricultural lands are dominated by small hobby farms.

Water quality issues

Areas of Oakland Bay and Hammersley Inlet fail to meet state water quality standards for fecal coliform bacteria. In many marine waters, water quality standards for bacteria are set to protect shellfish harvest. Protecting the significant commercial and tribal shellfish harvest in Oakland Bay was an important consideration in beginning this water cleanup process.

Several tributaries to Oakland Bay and Hammersley Inlet also have bacteria problems. In freshwater, too much bacteria can pose a health risk to people swimming, fishing, or playing in the water. Bacteria can get into our waters from untreated or partially treated discharges from wastewater treatment plants, from improperly functioning septic systems, and from livestock, pets and wildlife. Contaminated tributaries also contribute to bacteria concentrations in Oakland Bay and Hammersley Inlet. Reductions in bacteria concentrations are needed in Campbell, Cranberry, Deer, Uncle John, Malaney, Shelton, Johns, Mill, and Goldsborough Creeks.

Oakland Bay near the port, Washington State.  Photo courtesy of Anise Ahmed, WA Dept. of Ecology.

The Status

Protecting the significant commercial and tribal shellfish harvest in Oakland Bay was an important consideration in beginning this water cleanup process. To protect shellfish harvest, salmon, and recreational use of area water bodies, Ecology and local partners began a cleanup process in the spring of 2003.

The first step of the process was a water quality study. Starting with an evaluation of existing water quality data, Ecology and the technical advisory group designed a study plan to fill information gaps. After completion of the plan for the bacteria study, called the Quality Assurance Project Plan (QAPP), field work for the study began in fall 2004. The Squaxin Island Tribe conducted most of the field work for the temperature study. Field work for the studies was conducted throughout 2005. During 2006-07 the data was compiled, analyzed, and modeled.

The bacteria study evaluated source areas for bacteria. It calculated how much bacteria the water bodies can assimilate and remain healthy, and how much sources need to be reduced. Ecology calculated target concentration levels to protect marine waters, because marine standards for bacteria are more stringent than freshwater standards. The study findings provided the basis for developing cleanup recommendations.

Ecology released and made available the bacteria study report and summary cleanup plan (more commonly referred to as the total maximum daily load, or TMDL) for public review and comment May 9 - June 8, 2011. After addressing comments, Ecology submitted the report to the federal Environmental Protection Agency (EPA) for consideration on June 30, 2011. The EPA approved the TMDL on August 18, 2011. Included in the TMDL were implementation plan specifics. The EPA does not approve those sections of the TMDL.

Now that EPA has approved the bacteria report, Mason County's Action Plan provides the foundation for the cleanup plan. Cleanup work includes continued monitoring, evaluation, and adjustment of cleanup strategies to achieve bacteria reduction targets.

Technical information

Progress Reports:

Quality Assurance Project Plan - Fecal Coliform (final) (Ecology Publication)

Oakland Bay, Hammersley Inlet, and Selected Tributaries Fecal Coliform Bacteria Total Maximum Daily Load: WQIR-IP (Ecology Publication)

Oakland Bay Sediment Investigation (Ecology's Toxics Cleanup Program website)

Partner websites


Back to top of page

Last updated May 2013
  Map of Kennedy-Goldsborough watershed, WRIA 14, Washington State.


WRIA: #14 (Kennedy-Goldsborough)
County: Mason

Water-body Names:
Oakland Bay
Hammersley Inlet

Fecal coliform

# of TMDLs:
Fecal coliform - 8

Fecal coliform TMDL approved by EPA.
Has implementation plan.

Contact Info:
Andrew Kolosseus
Phone: 360-407-7543
Email: Andrew.Kolosseus@ecy.wa.gov

Southwest Region
Department of Ecology
Water Quality Program
P.O. Box 47775
Olympia, WA 98504 -7775

Anise Ahmed
Phone: 360-407-6767
Email: Anise.Ahmed@ecy.wa.gov

Environmental Assessment Program
Department of Ecology
P.O. Box 47600
Olympia, WA 98504 -7600