Presentation Abstract

The aftermath of the 2001 Nisqually earthquake revealed that Seattle’s seawall was decaying and in need of replacement. The resulting seawall replacement project presented an opportunity to replace vertical featureless walls with more complex and productive habitat. Several years before the new seawall was designed, the City of Seattle invited University of Washington biologists to participate in developing concepts for improved seawall habitat. This resulted in collaborations with several City of Seattle departments, during which we designed, deployed, and evaluated large habitat panels that tested several types of slopes and textures. Four years of monitoring algae, sessile invertebrates, and epibenthic organisms demonstrated that important biological “ecosystem engineers” benefited from adding texture and relief to seawalls. For example, compared to simple flat treatments and the existing seawall, recruitment of mussels was increased on panels with cobble texture, and rockweed was more abundant on high relief “finned” and “stepped” panels. Species richness of biota was also higher on surfaces with higher habitat complexity. This project represents a successful test of ecological engineering concepts, and the findings are being incorporated into the seawall that is currently being built. The City’s 10-year monitoring and adaptive management plan will allow for continued evaluation of these types of habitat enhancements on a larger scale. Invited comment: Mark Mazzola, Environmental Manager for the Seattle Department of Transportation

Session Title

Session S-05G: Beyond the Numbers - How Science Informs Decisions to Catalyze Action

Conference Track

Planning Assessment & Communication

Conference Name

Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)

Document Type

Event

Start Date

1-5-2014 10:30 AM

End Date

1-5-2014 12:00 PM

Location

Room 6E

Genre/Form

conference proceedings; presentations (communicative events)

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Subjects – Topical (LCSH)

Sea-walls--Design and construction--Environmental aspects--Washington (State)--Elliott Bay; Marine mammals--Washington (State)--Elliott Bay; Marine ecology--Washington (State)--Elliott Bay; Shore protection--Washington (State)--Elliott Bay

Geographic Coverage

Salish Sea (B.C. and Wash.); Elliott Bay (Wash.)

Rights

This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.

Type

Text

Language

English

Format

application/pdf

COinS
 
May 1st, 10:30 AM May 1st, 12:00 PM

Adding Texture and Relief to Seattle’s New Seawall, an Application of Ecological Engineering

Room 6E

The aftermath of the 2001 Nisqually earthquake revealed that Seattle’s seawall was decaying and in need of replacement. The resulting seawall replacement project presented an opportunity to replace vertical featureless walls with more complex and productive habitat. Several years before the new seawall was designed, the City of Seattle invited University of Washington biologists to participate in developing concepts for improved seawall habitat. This resulted in collaborations with several City of Seattle departments, during which we designed, deployed, and evaluated large habitat panels that tested several types of slopes and textures. Four years of monitoring algae, sessile invertebrates, and epibenthic organisms demonstrated that important biological “ecosystem engineers” benefited from adding texture and relief to seawalls. For example, compared to simple flat treatments and the existing seawall, recruitment of mussels was increased on panels with cobble texture, and rockweed was more abundant on high relief “finned” and “stepped” panels. Species richness of biota was also higher on surfaces with higher habitat complexity. This project represents a successful test of ecological engineering concepts, and the findings are being incorporated into the seawall that is currently being built. The City’s 10-year monitoring and adaptive management plan will allow for continued evaluation of these types of habitat enhancements on a larger scale. Invited comment: Mark Mazzola, Environmental Manager for the Seattle Department of Transportation