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Since the Drayton Harbor Shellfish Advisory
Committee was first formed in 1995, there have been numerous attempts
to determine the possible sources of fecal coliform within the
watershed. Because no “smoking gun” has been found
as the main source of the pollution, comprehensive studies that look at
how the entire system works may help to target several specific problem
areas. Looking at the circulation patterns within and around Drayton
Harbor is one way to track how fecal coliform bacteria move throughout
the system. Having a better handle on bacterial transport can assist
groups in developing more targeted studies focused on a particular
area/source.
Semiahmoo
Bay
Shared
Waters Circulation Study 2002/2003- In 2002, the Shared
Waters Roundtable Group, a trans-boundary organization of Canadian and
United States citizens and agencies, contracted with Hay and Company
Consultants, Inc. to create a circulation model for Semiahmoo Bay,
incorporating data from both Canada and the United States. The
following is a list of the project contributors that funded this work:
Environment Canada, Georgia Basin Ecosystem Initiative, the Greater
Vancouver Regional District, the City of Surrey, the Nooksack Tribe and
the Puget Sound Action Team.
The circulation model looked at impacts and
loading from several Canadian sources (Nickomekl, Serpentine and Little
Campbell Rivers) and from several U.S. sources (Dakota and California
Creeks and the sewage treatment plant outfall for the City of Blaine).
A report was produced as part of this project; it documents the
methodologies used as well as the results obtained from the modeling.
Semiahmoo
Bay Circulation Study and Figures
(This file is 3.98MB, if you can't download it a copy is available for
review at Water Resources). Please note: there are several
additional appendices associated with this report that provide
additional details on the data from the project. Copies of these
appendices, along with the report and figures, are available for review
at the Water Resources Library (322 N. Commercial St., Suite 110,
Bellingham, WA).
Blaine Marina/Drayton Harbor Circulation Studies
In 2002, the Drayton Harbor
Shellfish Advisory Committee asked the Department of Health (DOH) to
provide direction on what criteria DOH would need in order to consider
a re-classification of portions of the harbor. One of DOH’s
recommendations was that circulation work occur in and around the
Blaine Marina to determine whether waters in this area (which have high
fecal coliform counts) have the ability to impact other areas of the
harbor, in particular Sites #4 and #6, which are closer to the marina
than Sites #3, #5, and #12, are which represent the Community Oyster
Farms shellfish beds.
In response to this recommendation, several preliminary circulation
studies were conducted in August and September 2002.
August
19, 2002 Circulation Study Report
September
9, 2002 Circulation Study Report
September
10, 2002 Circulation Study Report
This
preliminary work indicated that there was little surface movement of
water within the Blaine Marina- surface water within the marina did not
leave the marina. These preliminary studies made it evident that
additional work would need to be done, incorporating deep-water drogues
(floats) to better understand the water circulation patterns in and
around the marina area.
After sharing these initial studies with DOH and
receiving input and feedback from DOH staff on how additional work
should be accomplished (appropriate depths for deep-water drogues,
deployment times, deployment locations, etc.), an initial field
assessment was conducted on January 27, 2003
to determine if the drogues would work correctly, etc. After the
initial trial, circulation studies were conducted on four dates in
March and April of 2003: March 20, 2003, March 21, 2003, March 22, 2003
and April 17, 2003.
Results
from these studies indicate that it is the deeper water that is leaving
the Blaine Marina and it leaves the marina and then returns to the
marina, indicating it has no impact to the shellfish growing areas.
Drogues placed in the harbor on a returning tide generally tended to
track straight in and to the southeast slightly, indicating that waters
from Sites #15 and #8 probably aren’t affecting the shellfish
beds at Sites #4 and #6. Follow-up work will probably occur after
additional discussions with DOH staff. Dye studies at Sites #8 and #15
will hopefully be conducted with DOH staff in July of 2003 to further
define the level of impact water quality at these sites might have on
the shellfish beds. As a result of this circulation work, it is hoped
that stratified fecal coliform monitoring can occur to give a better
picture of fecal coliform impacts at various depths.
Blaine
Harbor Circulation Studies Report 2003
Photos courtesy of Geoff Menzies
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