1. Net Gain of Ecological Function Observed on
Bainbridge Island Shorelines from 1997 to 2010
Compiled from Hydraulic Project Approvals (HPAs) issued by the
Washington Department of Fish & Wildlife.
by Albert Greiner for Bainbridge Shoreline Homeowners
with editorial assistance by Ken Sethney
Summary
New construction, damage repair, and restoration projects undertaken since our city’s Shoreline
Management Master Program was enacted, have resulted in a significant gain of shoreline
ecological function. When combining the data from overwater structures, shoreline modifications
and restoration projects, we have seen the following gains over the last thirteen years:
• 750 linear feet reduction of hard shoreline armoring
• 1,536 square feet reduction of opaque overwater structures
• 523 feet of creosote treated wood bulkhead have been replaced
• 583 creosote treated pilings have been or will be removed
• 4,036 cubic yards of sand & gravel will nourish beaches
• 28,518 square feet of native vegetation have been planted
• 125,676 square feet of tideland have been or will be restored
• 196,020 square feet of eelgrass have been or will be planted
Conclusion
“No net loss” was not the standard in 1996, but it is today. It is clear that existing policies are
more than adequate to mitigate loss and provide substantial gains.
During their presentation at City Hall, Department of Ecology representatives made it clear that
“no net loss” can be applied to an entire jurisdiction rather than a single project. Doing so
spreads the incentives for and benefits of restoration across the entire island instead of focusing
on individual homeowners or project developers.
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2. Docks and Overwater Structures
• 52 HPAs were issued from 1997 to 2010
• 8,796 square feet of opaque dock deck was replaced with grated deck
• 7,260 square feet of new opaque deck was installed
• 1,772 square feet of new grated deck was installed
• 283 creosote treated pilings were removed
• 381 non-toxic pilings were installed
According to the Army Corps. of Engineers, Washington Department of Fish & Wildlife (WDFW),
and local planners, grated decking is better than opaque decking. Since 1996, we have seen a
net reduction of 1,536 square feet of opaque overwater structures.1
While examining the HPA documents, we observed that most decks and floats are less than 60
feet long. The area of the island’s tidelands extending 60 feet from the ordinary high water mark
is approximately 16,790,400 square feet.2
New overwater structures, both opaque and grated, total 9,032 square feet.3 This constitutes a
change of about 0.054% or 5.4 hundredths of one percent in thirteen years, or 4 thousandths of
one percent per year.
That amounts to one square foot of new dock surface for every 1,859 square feet of tideland
area 60 feet from the OHWM.
Summary: Any loss of ecological function caused by such a minute yearly change is
far outweighed by the net reduction in opaque overwater structures.
1 7,260 square feet - 8,796 square feet = -1,536 square feet
2 53 miles X 5,280 feet/mile X 60 feet = 16,790,400 square feet
3 1,772 square feet + 7,260 square feet = 9,032 square feet
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3. Shoreline Modifications
We found shoreline modification permits for bulkhead repairs, removals, replacement and
installations, plus restoration permits for private shorelines.
• 68 permits were issued from 1997 to 2010 4
• 1,690 linear feet of new rock bulkhead was installed
• 507 linear feet of soft armoring was installed
• 405 linear feet of concrete bulkhead was replaced by lower reflectivity rock bulkhead
• 523 feet of creosote treated wood bulkhead was replaced by rock bulkhead
• 17,036 square feet of tideland gained due to bulkhead removals & landward relocations
• 2,806 linear feet of beach was improved by installing large woody debris
• 5,018 square feet of native vegetation was restored
• 4,036 cubic yards of beach nourishment (aka “fish
mix”) has been required as mitigation over various time
periods
This is equal to 230 tandem wheeled dump truck loads,
enough to spread 4.5 inches of sand and gravel
over the island’s entire tideland area.
The net permitted gain of 1,690 feet of angular rock armoring is 0.6% of the island’s 53 miles of
shoreline.5 This is slightly more than 1/16th of an inch per foot of shoreline, and amounts to an
armoring rate of 130 feet per year.
Approximately 50 percent of Bainbridge Island’s shoreline has been modified in the past.6 At
130 feet per year, it would take 1,076 years to modify the remaining 50 percent if it were lawful
to do so.7 However, this ignores the restoration projects mentioned below which have (or will)
result in a 750 foot net reduction of shoreline armoring.
Summary: Any loss of ecological function caused by such a minute yearly change is
far outweighed by moving structures landward, installation of soft
armoring and woody debris, and beach nourishment requirements.
4 We noted a large spike in bulkhead repairs following the severe 2005-6 winter storm.
5 1,690 feet / ( 53 miles x 5,280 feet/mile ) = .006 = 0.6%
6 Herrera, Addendum to the Summary of Science Report for Bainbridge Island, pg 14
7 50% x (( 53 miles x 5,280 feet/mile ) / 130 feet/year ) = 1,076 years
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4. Shoreline Restoration
The following were observed from sources reporting shoreline restorations on Bainbridge Island.
Most are classified as active projects. Blakely Harbor Park restoration goals are included but
that project is still being studied as to feasibility. We were unable to find data on the Waterfront
Park shoreline restoration, so bulkhead removal and shoreline restoration for that project is not
included in the following numbers.
• 2,440 linear feet of shoreline armoring removed
• 108,640 square feet of tidelands/marsh restored
• 870 cubic yards of debris removed from tidelands
• 23,500 square feet of nearshore vegetation restored to native species
• 196,020 square feet of eelgrass planed
• 300+ creosote treated pilings removed
• 435 linear feet of shoreline received large woody debris
• 265 feet of jetty to be removed (Blakely)
• 2,750 square foot structure to be removed (Blakely)
Summary: Restoration is intended to cause a net gain of ecological function. With
limited information, we have been able to track these significant gains.
Limitations of Data Included
• Hydraulic Project Approval (HPA) data was furnished under a public records request
made to the Department of Fish and Wildlife.
• All shoreline work requires an HPA before any city permit may be issued.
• Many HPAs are not specific as to tideland gains, so only those gains cited or calculable
from applications are included. There are more gains than totaled here.
• Many HPOs do not specify numbers of piles removed, so only those pilings enumerated
are included. More pilings have been removed than totaled here.
• The permits mentioned were HPA permits, not Bainbridge Island city permits.
• HPA permits do not show completion dates, so there is no confirmation that the
permitted work was actually completed.
• Personal communication from a COBI staff member indicates COBI has no reliable way
of reporting project completion.
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