Water Quality Improvement Project
Oakland Bay and Hammersley Inlet:
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.
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.
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)
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WRIA: #14 (Kennedy-Goldsborough)
# of TMDLs:
Fecal coliform - 8
Fecal coliform TMDL approved by EPA.
Has implementation plan.
Department of Ecology
P.O. Box 47775
Olympia, WA 98504 -7775
Environmental Assessment Program
Department of Ecology
P.O. Box 47600
Olympia, WA 98504 -7600