UW Floating Wetlands Project Phase I

Executive Summary:

Floating wetlands are an emerging green technology that grows native wetland plants on buoyant frames to mimic functions provided by natural floating wetlands which have been largely removed due to shoreline development.

We propose to create a UW Floating Wetlands Demonstration Project that would occur in two phases, with an end goal of installing floating wetlands demonstration prototypes along the University of Washington shorelines.  This proposal is a request for the funding of Phase I, a feasibility analysis to further investigate optimal locations, permitting, design, and long-term viability.  Phase II funding will be sought after feasibility is determined in Phase I and will comprise completing floating wetland implementation documents, obtaining permits, construction, installation, maintenance and evaluation procedures.  Improvement of Union Bay aquatic habitat and moderation of pollutant loads is anticipated through the deployment of these floating wetlands.  Furthermore, this project will serve as an example for other Seattle water bodies and showcase UW’s leadership role in green technology and public/community partnerships.

Research and implementation of floating wetlands has been conducted worldwide and, while there are freshwater floating wetland projects underway locally, implementation of these structures along the WRIA 8 shoreline would be unprecedented. Measured environmental benefits have included: carbon sequestration; reduction of phosphorous, ammonia, nitrogen, heavy metals, and other aquatic pollutants; reduction of biological oxygen demand and food chain re-connections; climate adaptation and water temperature mitigation; habitat re-creation; and shoreline protection and beautification. (Dodkins)  Particularly, implementation of floating wetlands in the Union Bay area has the potential to replace lost function in the migration corridor for juvenile salmon along the Lake Union and Lake Washington shoreline.  Permitting to install new shoreline structure will require considerable discussion, education, and design response which is why a feasibility study is required as a first phase.

Many studies and precedents have informed the Green Futures Lab’s work with floating wetlands thus far and prior work on floating wetlands can be viewed on the Green Futures Website at greenfutures.washington.edu.  Phase I would build upon work already underway by Landscape Architecture graduate students working through the Green Futures Lab, College of Built Environments, and also require outreach to students and faculty in other departments including: Aquatic and Fisheries Sciences, Environmental Science and Forestry, and Engineering.  The cost to advance this research is $11,379.00, which includes the employment of 2 graduate students for 20 hours per week for 10 weeks during summer 2016, and 8 hours a week for 10 weeks during autumn term, for a cost of $9979 with benefits. The remaining $1,400 will be used for materials and travel expenditures as detailed below.  In the future Phase II, students from these various departments would again be recruited to participate in detailed design, construction, installation and observation.

State and local agency awareness of the potential benefits of floating wetlands would be promoted through Phase I discussions,  and  implementation of Phase II would allow for outreach to the public and greater UW student body through the built demonstration wetlands, accompanying signage, publicity, and expanded partnerships for monitoring and stewardship of the project.

Dodkins, Ian, Anouska Mendzil, and Leela O'Dea. "Enterprise Assist: Floating Treatment Wetlands in Water Treatment: Treatment in Efficiency and Potential Benefits of Activated Carbon." Sustainable Expansion for the Applied Coastal And Marine Sectors (2014). Web.

Student Involvement:

In order to complete Phase I of the UW Floating Wetlands Project, this grant will provide funding for the work of two student team members for 20 hours (each) per week for 10 weeks during summer 2016 and for continued work of 10 hours a week through November. The scope of the work will consist of:

  • permitting research, including meetings with permitting agencies;
  • site feasibility research and analysis;
  • synthesis of existing habitat impact research;
  • materials research;
  • structural design research and prototype development;
  • construction of prototypes to test materials and structural design in response to regulations laid out in prior stages;
  • research of impact measurement techniques;
  • research and proposals for public educational opportunities
  • production of an illustrated design and feasibility analysis report

Through this process, students will gain valuable experience in: collaborating with an interdisciplinary team; conducting relevant research; translating new expertise into a design proposal; the iterative design process; exploring regulatory processes; and organizing and presenting their findings.  Additionally, there will be a division of responsibility between the two students that will provide specialized experiences such as researching construction techniques, providing biological expertise, leading volunteer efforts, and heading communications to other departments.  The work of these students will culminate in a cohesive document illustrating the anticipated environmental and social impact of the UW Floating Wetlands Project and a specific proposal for implementation.

These positions will be open to students in all UW departments and there will also be opportunities for volunteer positions.  Because of the nature of the project, cross-departmental collaboration between Built Environments, Aquatic and Fisheries Sciences, Environmental Science and Forestry, and Engineering will be necessary.  Likewise, conversations will be necessary between the students and regulatory agencies including UW Facilities Services; UW Real Estate, Planning and Management; UW Botanical Gardens; WA Department of Natural Resources; King County Water, Land, Resource Division; City of Seattle - Restore Our Waters; Seattle Shorelines; Save Union Bay Association; and local tribes among other organizations.  This lengthy list of collaborators illustrates the high level of commitment and organization required of those working on the project in order competently proceed with Phase II.  Most importantly, this level of collaboration will lay the groundwork for continued involvement from each of these departments during Phase II.

Education & Outreach:

As noted above, Phase I Feasibility will focus outreach on potential partners and student personnel;  this process will initially publicize the concept, benefits and application of floating wetlands. This will ignite awareness in our students, faculty and staff, and promote conversations with agency partners about floating wetland technology and urban habitat restoration.  As the project progresses, it will be publicized through the Green Futures Lab website’s “New and Events” page, with updates throughout project implementation (Phase II) such as permit approval, final design, and construction advertised via the website.

A significant part of Phase I is also researching how best to reach out to the public once the structures are built and implemented in Phase II.  The UW Floating Wetlands Project has the opportunity to be a unique and exciting deployment of a new technology and, as such, educating the public to the function of these structures is a top priority.  This goal will be addressed in Phase I through research on educational outreach and interpretation as well as through the actual design of the prototypes.

An important goal of Phase I is to raise awareness and education amongst internal organizations through the conversations required of the feasibility study. As we have continued to explore opportunities with floating wetlands, it has been necessary to approach many organizations regarding our proposal and few have been aware that this technology exists or of possible benefits gained by varying the design approach.  To date we have contacted individuals from the following agencies:

  • University of Washington Real Estate, Planning and Management
  • University of Washington Botanical Gardens (Union Bay Natural Area)
  • University of Washington Facilities and Services
  • UW Wetland Ecosystem Team, School of Aquatic and Fisheries Sciences
  • King County DNR, Water and Land Resource Division
  • King County Wastewater Treatment Division
  • City of Seattle, Restore our Waters
  • Seattle Public Utilities (SPU)
  • Department of Ecology NW
  • Washington Department of Fish and Wildlife (WDFW)
  • Washington Department of Natural Resources (WADNR)
  • Save Union Bay Association

This outreach has included presentations, conversations and resource distribution including the work of a graduate student affiliated with the Green Futures Lab who has created an online database of floating wetlands information at tinurls.com/floatingwetlandsSeattle.  In order to comprehensively analyze implementation feasibility, spreading an understanding of the ecology, engineering, potential design, and required permitting for floating wetlands across agencies is crucial.  This process will enrich possibilities for Phase II implementation and increase the creative and collaborative potential of future public education.  Involvement and support from organizations such as Save Union Bay Association will provide education and outreach far beyond our own reach to those within the greater UW community. 

Environmental Impact:
  • Living Systems and Biodiversity
  • Water
Project Longevity:

Determining the role of maintenance within floating wetland structures is crucial to the design analysis during Phase I. Having seen the critical role maintenance and its funding play in the long-term success of our Green Wall and Edible Green Screen project, we are gearing our design exploration of floating wetlands to low-maintenance and, ideally, something that will incorporate safely into the natural ecology of a selected site. Working off of our existing body of knowledge, we would like to explore different materials to assess their durability and, in contrast, their likelihood of biodegradation. Unlike our Green Wall, the floating wetlands are physically less accessible which would require a design that is capable of sustaining itself with little to no maintenance. Again, this is something that we view as critically important and would require substantial consideration within our feasibility study.

Environmental Problem:

As Puget Sound and its contributing waters experiences an increase in waterway traffic, shoreline armoring, and stormwater runoff, valuable shoreline habitat has decreased dramatically.  Only about 25% of Seattle’s shorelines are beach, naturally vegetated, or landscaped leaving 75% of surfaces as rapid runoff points for pollutants which, in turn, degrade and jeopardize a number of plant and aquatic species. (Toft 2003)  Although Union Bay provides relief from the the rest of Seattle’s heavily developed shorelines, its habitat has, nonetheless, been heavily compromised.  As a result of development and land uses, wetland ecosystems in Seattle have experienced “significant losses and degradation.” (Puget Sound Partnership 2011)

The UW Floating Wetlands looks to capitalize on the adjacent Union Bay Natural Area’s existing vegetated shoreline - the second largest in Seattle - to better understand how installed floating wetlands can mimic those that are occurring naturally.  Discussion with the Fred Hoyt at the Union Bay Natural Area during the feasibility phase will help to establish a significant precedent to the benefits of monitored aquatic vegetation and would provide evidence supporting Phase II implementation of floating wetlands as rehabilitative habitat for the WRIA 8 shoreline.

Across the globe, floating wetlands have been deployed with positive results in carbon sequestration; reduction of metals and pollutants; climate adaptation and water temperature mitigation; habitat renewal; and shoreline protection and beautification.  A growing body of research exists that supports these claims including Floating Treatment Wetlands (FTW) in Water Treatment: Treatment efficiency and potential benefits of activated carbon by Dr. Ian Dodkins, Anouska Mendzil, and Leela O’Dea which details the physical, biogeochemical, microbial, and vegetative components of floating wetlands and their positive impact on aquatic environments. Through the feasibility study, students will be able to compare these findings in discussion with local scientists and agencies to establish a list of benefits and monitoring practices specific to our proposed locations.

There are relatively few floating wetland projects in the Puget Sound area, and even fewer that are publicly accessible. Additionally, concern for the perceived potential ambush habitat beneath overwater structures has impeded adoption of floating wetlands as a viable strategy to actually create better salmon habitat.  Our initial prototypes have addressed this issue by allowing light penetration and partially submerging the floating wetlands to provide a shallow surface column of water that may serve as refuge for the vulnerable smaller and juvenile salmonids. Funding of the Phase I Feasibility Study will allow us to meet with regulators to present such innovative designs and explore approaches and standards that will allow future permitting of such habitat structures. Construction, installation and interpretation of floating wetlands in a subsequent Phase II will allow evaluation of the efficacy of such prototypes to potentially institutionalize their more widespread adoption on freshwater shorelines, and to inspire and educate the UW community and the public on their multiple benefits.

Explain how the impacts will be measured:

We will measure the impact of Phase I Feasibility Analysis through the impact of our outreach to potential partners.  This will take the form of committed partnerships at the UW and with governmental and nonprofit organizations for Phase II implementation; commitment  of matching funding for Phase II implementation; student interest and engagement in assisting in construction of the prototypes; and encouragement from agencies to apply for permits to construct the floating wetlands in Phase II.

Although there exists an extensive body of literature on the positive impacts of floating wetlands, in order to comprehensively understand their potential impact on surrounding habitats specific to the UW waterways, conversations must be had with involved partners including Aquatic and Fisheries Sciences, Environmental Science and Forestry, and Engineering regarding monitoring in a future phase.  Through these conversations, opportunities and potential for monitoring and measuring the impact of floating wetland prototypes during Phase II will be identified and conveyed in a comprehensive document to be used during Phase II.  Through exploration of monitoring opportunities, there is also potential in finding sources of funding for monitoring the wetlands, once constructed, over several seasons;  this would also constitute a measure of impact of the Phase I Feasibility Analysis.

Total amount requested from the CSF: $11,379
This funding request is a: Grant
If this is a loan, what is the estimated payback period?: 0months


ItemCost per ItemQuantityTotal Cost
Student Employment$15/hour + 18.8% Benefits2 Students @ 280 hours each$9,979.00
Materials for design prototypes including: growing medium, raft material, plants (based off of prices for constructed floating wetland prototypes)$3004$1200
Travel Expenses for exploratory trips to nearby floating wetlands including Hicklin Lake$.54/mile + $31.153$200

Non-CSF Sources:

Project Completion Total:


TaskTimeframeEstimated Completion Date
Contact permitting agencies2 WeeksJuly 1
Meet with Permitting AgenciesOn-goingNovember 1
Contact UW affiliates2 WeeksJuly 1
Meet with UW affiliatesOn-goingNovember 1
Research Materials and Site Feasibility6 WeeksAugust 15
Develop Prototype Designs3 WeeksAugust 15
Prototype Construction and Testing6 WeeksSeptember 23
Develop Implementation Plan2 WeeksOctober 21
Develop Educational Plan2 WeeksOctober 21

Project Approval Forms: