Kincaid Ravine Bioswale Hydrological Assessment

Executive Summary:

Funding for a feasibility and assessment study on potential hydrologic modifications and designs for a bioswale in Kincaid Ravine will not only help address the issue of flooding on the Burke-Gilman Trail at the edge of Kincaid Ravine, but will also add to the ongoing efforts to restore the ecological functions and habitat of the previously underutilized and ecologically degraded four acre open space located in the northeast corner of campus.  This assessment will focus on characterizing the quality and quantity of the water moving through Kincaid Ravine and determine the feasibility of constructing a bioswale that will help alleviate flooding and allow for better stormwater treatment, storage and infiltration in Kincaid Ravine.  This will require lab testing for water quality and soil and some hydrologic monitoring and modeling to determine the amount of water moving through the ravine during the wettest months.  In congruence with the soil and water quality testing (which will be done on campus), we will use outside consulting from the group 12,000 Rain Gardens in Puget Sound ( to help provide:

  • Assessment of current hydrology (approximate volumes and sources of water, outflow volumes, and soils assessment)
  • Bioswale feasibility assessment
  • Summary report of hydrology and feasibility
  • Bioswale basic design (approximate elevations and planting plan)   

Developing this assessment study instead of moving hastily into design and construction is a prudent first step in properly addressing the hydrology issues in Kincaid Ravine and making sure the numerous groups and administrative interests associated with Kincaid Ravine are all satisfied with the work going forward.  Meeting with UW Landscape Architect Kristine Kenney and Campus Grounds Manager Howard Nakase (who would be involved with future maintenance in Kincaid Ravine) it was strongly recommended that an assessment study would be the first step in addressing the hydrology problems in Kincaid Ravine.  Kristine and Howard, along with UW Environmental Planner Jan Arnst and other groups like the UW chapter of the Society for Ecological Restoration, UW Transportation Services, UW Sustainable Stormwater and students and classes in the School of Environmental and Forest Sciences are all very excited about this project and want to be involved in the process.  The projected cost of this project, including the water quality testing and outside consulting will be 5,000 dollars.

Student Involvement:

The restoration work at Kincaid Ravine already involves multiple graduate students from the School of Environmental and Forest Sciences (SEFS), undergraduate classes in Environmental Science and Resource Management (ESRM) and the University of Washington chapter of the Society for Ecological Restoration (SER).  SER and the Kincaid Restoration Team hold regular volunteer work parties in Kincaid Ravine and the site will continue to serve as a laboratory for graduate and undergraduate students to work with and study hydrology, soils, ecological restoration and wildlife.  SER and students in SEFS will continue to lead these volunteer opportunities and work to further develop relationships with project partners on campus, such as the UW Transportation Services, UW’s landscape architect, UW grounds crew management and off campus groups such as 12,000 Rain Gardens in Puget Sound and EarthCorps, who have been helping in the restoration efforts in Kincaid Ravine.  A creation of a bioswale will only diversify the opportunities for people and groups to get involved. 

Since work began in Kincaid Ravine there has been an influx of student groups, administrators and local community organizations with strong interest in restoring Kincaid Ravine.  The momentum got started as a Masters of Environmental Horticulture (MEH) final project by Martha Moritz in 2013.  Martha recruited Matt Schwartz who is the current Kincaid project leader and also the UW Sustainable Stormwater Coordinator.  Matt recruited current first year MEH student Dan Hintz to work on wetland hydrology and restoration and the plan is to continue to foster opportunities for MEH and other SEFS students to conduct research and applied projects in Kincaid Ravine.  This is similar to how work is done at the Center for Urban Horticulture (CUH) and we feel Kincaid Ravine provides similar opportunities for projects and research but in a totally different forested ecosystem.  Kincaid Ravine is also host to applied restoration projects conducted by students from the ESRM restoration capstone courses (ESRM 462-464).  This is the second year students from these classes have be assigned a plot of land in Kincaid Ravine and are responsible for designing and implementing a restoration plan for their plot.  The UW Society for Ecological Restoration also holds regular work parties in Kincaid Ravine and these opportunities are open to all students at UW. 

In less than two years myriad groups of UW students have become involved with work in Kincaid Ravine in one form or another.  This would not be possible without the Kincaid Restoration Team constantly working to develop buy in and support from administrative groups on campus and fostering relationships with organizations off campus.  UW landscape architect Kristine Kenney has been invaluable giving support to the restoration efforts in Kincaid while sharing her ideas and visions for the ravine moving forward.  We have also met with staff from UW Transportation Services to discuss how plans for a bioswale in Kincaid Ravine could be incorporated with efforts to upgrade the Burke-Gilman Trail within the next few years.  UW Environmental Planner Jan Arnst has also been incredibly supportive with identifying what sort of permitting and local regulations will need to be followed when developing the bioswale project.  This administrative support, along with support from SEFS faculty such as Kern Ewing, Jim Fridley and Susan Bolton, have allowed for the restoration efforts in Kincaid Ravine to gain a lot of momentum. 

This momentum is only further aided by off campus groups such as EarthCorps and 12,000 Rain Gardens in Puget Sound.  EarthCorps has been the primary contractor for the restoration work in Kincaid Ravine.  Their crews, which specialize in ecological restoration, have been removing invasive species and installing native species throughout Kincaid Ravine in 2014.  EarthCorps Project Manager Kym Foley has also been instrumental supporting this project and even received money from King Conservation District’s (KCD) neighborhood grants program to supplement the costs of their crews working in Kincaid Ravine.  Kym and EarthCorps are excited to provide any technical advice and crew support for any wetland hydrology modifications and plantings, such as the bioswale project.  Aaron Clark, program manager at 12,000 Rain Gardens in Puget Sound, has also been very supportive answering questions about potential wetland hydrology improvements in Kincaid Ravine.  If funding for the bioswale assessment is approved, Aaron will serve as the main consultant on the bioswale assessment and feasibility study.  We choose Aaron due to his ongoing support of this project, his in depth experience with designing and installing rain gardens and the fact that he will be more than willing to make the assessment and feasibility study a collaborative process with members of the Kincaid Restoration Team.  This will allow students involved with Kincaid Ravine to assist and learn from the process Aaron will go through to conduct the site assessment, feasibility study and potential designs for the bioswale.  Lastly, we will be reaching out to Raedeke Associates, Inc.  to help with the feasibility and site assessment since they are the group that did the original wetland delineations in Kincaid Ravine. 

The network of students, faculty, administrators and local environmental organizations has already made Kincaid Ravine a successful project on the UW campus.  However, it is necessary to keep this momentum going and make sure all stakeholders continue to be informed and involved with the work in Kincaid Ravine while also continuing to search for new groups and students who might have an interest in Kincaid Ravine.  The goal to make Kincaid Ravine a working laboratory for ecological restoration and habitat recovery while also serving as a tranquil open space for students and visitors to campus can only be accomplished with the support and efforts of this multitude of stakeholders.

Education & Outreach:

Restoring the habitat and ecological functions in Kincaid Ravine is a major priority, but one that must go hand in hand with the need to educate people about the importance of these ecological restoration efforts and also let them know how they can get involved or use similar practices to solve environmental problems throughout the region.  The design and creation of a bioswale will only give further opportunity to use Kincaid Ravine as a laboratory and possibly serve as a model of how to create bioswales in urban forests.  The bioswale will give opportunities to study wetland hydrology, soils and the effect plants have on removing pollutants from water and soils.  Kincaid Ravine will also be used to host interpretive signage about the restoration achievements and goals.  The site already has the advantage of high visibility next to the Burke-Gilman Trail and this visibility will be used to make sure that Kincaid Ravine is an example of how to re-establish healthy forest ecosystems. 

The Kincaid Ravine Restoration Team has already received permission from the UW landscape architect to install a bench and interpretive sign at the edge of Kincaid Ravine.  The location of this sign and bench will be very close to where the bioswale would be located.  The bench and sign would allow for a bioswale to really catch the attention of users of the Burke-Gilman Trail as they enter and leave campus.  We will post contact information and “ways to get involved” with the interpretive signage.  Not only would a bioswale improve the “view” from the trail, but it would also be a visual example of the type of projects people can incorporate into their properties and neighborhoods.  We not only want to publicize why the bioswale is important to the wetland hydrology in Kincaid Ravine, but also make it very clear and well known that this type of “rain garden” technology is relatively simple and can be done on small scales in people’s yards, at schools and around parking lots.  It will be important to emphasize the impact that bioswales and rain gardens can have on the greater public good in terms of how they can address stormwater pollution and overflow issues in Seattle.  This is another reason why we are working with 12,000 Rain Gardens in Puget Sound.  The Kincaid Ravine bioswale will be registered with 12,000 Rain Gardens and we will be contacting City of Seattle, King County and Department of Ecology to make sure this project falls within their respective goals and objectives for stormwater management and wetland protection. 

Besides continuing to ensure Kincaid Ravine and the potential bioswale provides a place for education, interpretation and restoration work parties and projects, we will continue to search for ways to get information about the progress in Kincaid Ravine out to the public.  Project Leader Matt Schwartz already writes monthly news updates to all of the involved constituents with Kincaid Ravine.  There are plenty of other opportunities along these lines such as writing a story for the school paper and presenting to ESRM undergraduate classes and other campus groups about the work in Kincaid Ravine and ways to get involved.  While in a short amount of time Kincaid Ravine has already become a project with many interested groups and stakeholders, it will be paramount going forward to continue to search for opportunities to inform the UW and outside community about the work done in Kincaid Ravine.

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

The need for the site assessment and the development of a bioswale design for Kincaid Ravine is necessary in determining a plan for a project that will fit within the landscape and be sustainable with limited maintenance over a long period of time. It is important to spend this effort on the assessment and design phase to ensure the bioswale functions properly, limits flooding, is suitable for the average amount of water on site, and matches the goals and objectives from other University of Washington interests. Once all of this is figured out through the assessment study, the next step will be to construct the bioswale. If all goes well this would be the end of the main phase of this project, hopefully completed in the next year and a half to two years. There will be need for some maintenance of the bioswale, but it should not require regular funding. The removal of sediment, invasive species and other minor maintenance of the bioswale will be carried out by students working in Kincaid Ravine and be assisted by the UW grounds management crews. One big issue going forward will be funding for the actual bioswale construction. While it is still early to tell the scale and cost of this project, it is our goal to build a bioswale with minimal intrusion into the wetland. This will help limit the need for permitting, reduce the risk of adversely impacting the wetland and hopefully keep the cost for the construction at a reasonable level. A real rough range for the cost of bioswale construction in Kincaid Ravine is anywhere from 5,000 to 30,000 dollars based on the amount of excavation and materials needed to bring in. The assessment and feasibility study will attempt to hone in on a more accurate cost estimate. While I will not rule out looking to CSF to help fund some of this, I also know CSF has already been incredibly supportive of the work in Kincaid Ravine and I have already identified a few potential grant opportunities to help supplement future funding needs. This includes the Rose Foundation Puget Sound grassroots grant program and King Conservation District Seattle Municipal Partnership fund. I will also continue to explore more options going forward.

Environmental Problem:

Wetlands are considered the “kidneys” of the landscape due to their excellent ability to store and treat water from contaminated sources.  However, a key component that allows for this ecological function to be beneficial is the amount of time it takes the water to pass through the wetland system, which is called the hydroperiod.  At Kincaid Ravine, stormwater flows have created an incised channel that quickly funnels water down from the ravine where it spills out along the Burke-Gilman Trail.  Slowing down this hydroperiod would allow for more groundwater recharge, sediment deposition, phytoremediation (ability for plants to remediate toxins in the soil and water) and more diverse wetland habitat for a variety of plant and wildlife species.

Bioswales are landscape features designed to slow down the flow of surface and stormwater runoff.  This process, along with the help of wetland vegetation, allows for the removal of sediment and contaminants.   A bioswale at the bottom of Kincaid Ravine would help slow the flow down and remove sediment and pollutants from the water with the help of a diverse planting of native sedges, rushes, grasses and shrubs in and on the edges of the bioswale.  A thorough site assessment and a bioswale design that functions properly in the landscape are crucial first steps in achieving the goals of restoring and enhancing wetland ecological functions, limiting flooding on the Burke-Gilman Trail and providing an opportunity for education and outreach due to the Kincaid Ravine’s high visibility near the entrance of campus.

Explain how the impacts will be measured:

It is somewhat difficult to provide measurable impacts for this project since it is an assessment and feasibility study.  That being said, the main success of this project will be determined by taking the deliverables created (listed in executive summary) for the assessment study and using them to push towards the actual construction and implementation of a bioswale.  If for whatever reasons that cannot happen, these documents will still be incredibly useful in analyzing other plans for wetland restoration and hydrology modifications.  While designing and implementing a bioswale for hydrologic purposes is still priority number one, the approximately 1 acre of delineated wetland in Kincaid Ravine will be put into restoration in the coming year.  A bioswale provides the best potential to store water, reduce flooding and treat contaminated water and soils in Kincaid Ravine.  The construction of a bioswale will allow for measurable impacts such as amount of water stored, diversity of plant species, and we will also be able to compare the water quality at the site pre and post bioswale.  We can also study the quality of the water entering the bioswale versus water that has passed through or remains in the bioswale to show effectiveness of water quality treatment.

Total amount requested from the CSF: $5,000
This funding request is a: Grant
If this is a loan, what is the estimated payback period?:


ItemCost per ItemQuantityTotal Cost
Water Quality Testing - metals$12.50 per sample10$125
Water Quality Testing - carbons$100 per sample5$500
Soils Testing$17 per sample20$340
sample prep$45 per hour5 hours$235
Consulting$75 per hourabout 50$3,800

Non-CSF Sources:

Project Completion Total:


TaskTimeframeEstimated Completion Date
Water and Soil Testingcan be done immediately after funding is securedMay 2015
Consulting for assessment studyAaron at 12,000 Rain Gardens is able to work this into his schedule as soon as we find out if this project is funded. His assessment and report writing will be done over 1 to 2 month periodJune 2015