Roxhill Wetland Restoration Project

Roxhill Park and Bog as they exist today. 3D rendering from iMaps and satellite images.

This is a dedicated page that WWRHAH will maintain for the course of the work of the Roxhill Bog Committee as a clearing house of information and documents related to their work. The long term goal we are pursuing is to help protect the headwaters of Longfellow Creek in West Seattle and to safely repair the Roxhill Bog to it’s original wetland state, without harm to the park’s neighbors.

The research of our Bog Committee has turned up evidence that this may be possible, as we learned in our March 6th, 2014 WWRHAH Community Council meeting (our meeting’s [full notes here]; the Bog details are toward the end).

If you have or know of any information related to this work in progress, please e-mail any details you know to If you would like to discuss this at one of our meetings or have materials that you would like to share in person, we also meet monthly for our regular WWRHAH meetings on the 1st Tuesday of every every month in the upstairs meeting room of the SW Branch of the Seattle Public Library at 9010 35th Ave SW, Seattle, WA 98126. This is at the intersection of 35th Ave SW and SW Henderson Street. Our meetings are from 6:oopm to 7:45pm.

Table of contents:

  • Why is Roxhill Bog so important?
  • What’s wrong with the bog today?
  • What is WWRHAH doing to fix this?
  • The history of Roxhill Park’s Bog.
  • Historical documents related to Roxhill Bog.
  • Letter from WWRHAH to the City of Seattle and King County.
  • Project media coverage.
  • Contact us if you know more.

Why is Roxhill Bog so important?

This quote from a book about Seattle’s natural wonders basically sums it up:

As the drainage basin for sixty surrounding acres, Roxhill Bog collects sediments and pollutants from rain and storm water run off. Plants absorb some pollutants while the spongy peat soil helps filter sediments. At the headwaters of Longfellow Creek, this wetland acts as an essential water filter for a 3.5-mile long waterway that’s home to coho salmon, ensatina salamanders, and red foxes feeding downstream. The creek drains a 2000-acre watershed and is one of the few year round free-flowing creeks in Seattle.

— Nature in the City Seattle, by Kathryn True and Marie Dolan, Mountaineers Books; May 1, 2003

What’s wrong with the bog today?

  • The bog’s water levels are too low.
  • The bog’s water levels fluctuate too much.
  • The reduced water levels could eventually cause the destruction of the natural peat base, which may be irreversible.
  • There are several possible contributing factors to the low water levels, including possible flow thru the storm water drainage system and evapotranspiration from the trees, shrubs and forbs planted around the bog.
  • We can’t know the exact cause without a study.  SPU is currently helping with a preliminary study of the storm drainage system and our committee is looking at the evapotranspiration issue. In addition we need to examine the inflow of water to the bog and look for possible sources of additional water to support rehydration.
  • The current condition of the bog and park may be contributing to periodic flooding north along the Delridge corridor, all the way to the North Delridge neighborhood.

What is WWRHAH doing to fix this?

Bog trail, from Starflower 2007 report.

We’re currently researching this issue with Seattle City Parks, and are digging into records and the history of the project with them, Seattle Public Utilities, and King County.

Several solutions are possible including some sort of coffer dam between the bog and the storm drains, changes in surrounding vegetation and additional sources of water. Once all information is available and we have a completed history of all events and work done to the Roxhill Bog, we will be able to coordinate a proposal for the following four steps:

  • Develop a new park hydrology model.
  • Design hardware and/or vegetation changes and possible additional water collection systems.
  • The building and installation of it all Follow up study to make sure it’s working.
  • It will need to go through Seattle City Parks, Seattle Public Utilities, the King County Department of Natural Resources, and their Waste Water group.

The history of Roxhill Park’s bog

Roxhill Bog begins to form 10,000 years ago. Biologist estimates are that Roxhill’s 6 to 10 feet of peat took 10,000 years to accumulate. Source: 3

Westwood and Roxhill, 1953. The park, Westwood Village, and the school areas are all farms and wetlands, still.

For an idea of how old Roxhill Bog is, this Wikipedia article details the state of the world at it’s inception.

1895: USGS maps show two tributaries to Roxhill wetland. Source: 2

1920s: Much of the area was a swampy bog, as far east as 16th Ave SW, even up the hills. Source: 4

1930s: There were productive farms and a dairy on the Roxhill Park land just north of SW Roxbury Street, where today’s baseball fields are. Children played in a large pond north of that in the summer and ice skated on it in the winter. The area was owned by the Kodama family, Japanese farmers forced to relocate to internment camps during World War II. Source: 4

1953: Aerial photos show undeveloped wetland. Source: 1

1959: Aerial photos show 8-10 acre wetland.  Source: 2

1960: City receives some of the Roxhill Park land as a donation.  Source: 1 

W. Roxbury Paving. Peat Bog. 26th Ave. SW. and Barton. Mar 31, 1961.

1965: Westwood Village shopping center is finished by the Skinner Corporation and opens. Source: 4

1966: Skinner Corporation donates it’s land immediately south of Westwood Village across Barton to the Seattle Parks Department. Source: 4

1966: Main storm water line to the north was built. Dates of side lines would require a trip to the City’s document center.  Source: E-mail from SPU

1969: City regrades Roxhill Park and covers peat with 1.5-2 feet of topsoil to establish a park lawn.  Source: 2

1992: City adopts Longfellow Creek Watershed Action plan which includes goal of restoring historic headwaters in Roxhill Park.  Source: 2

Late 1990s: Lutheran Alliance to Create Housing (LATCH) selected by Seattle Housing Authority to be partner in development of Roxbury House and Village. Decision made to restore headwaters of Longfellow Creek. Parks became lead organization. Over $750K raised from individuals, private and public organizations.  Source: 1

Aerial of Roxhill Park, 1969.

1999: Neighborhood residents and other stakeholders begin planning with Parks. Starflower and 14 other organizations pledge support.  Source: 1 

2000: King County Department of Natural Resources completes a hydrology survey. It recommends completion of a full hydrology model and design of subterranean structures to regular water flow. Source: 2

2000: Phase 1 construction and planting. Peat cell 4 exposed. Source: 1

2002: Phase 2 construction and planting. Peat cells 1, 2 and 3 exposed. Source: 1

2007: Starflower and Seattle Urban Nature conduct assessment. Noted that at the end of phase 1, there was standing water through  summer in peat cell 4 (southern-most), but at the end of phase 2, no standing water in summer in any peat cell, though cell 4 has water most of the year. Source: 1

2013: The collar on an overflow pipe at the north end of cell 4 has long been too low, causing water that should flow to the northern 3 peat cells to flow into storm drains. During the summer of 2013 the collar height was corrected.  Source: Phil Renfrow, Seattle Parks

March 2014: Recent very heavy rains provided enough water to test the cell 4 drain collar height and the flow is corrected. However, cells 1, 2, and 3 remain deficient in water. Source: Phil Renfrow, Seattle Parks


1. Roxhill Park Stewardship Report. Starflower Foundation, 2008
2. Roxhill Park, Hydrologic Investigation and Recommendation. King County Wastewater Treatment Division, DNR. March, 2000
3. Nature in the City Seattle, by Kathryn True and Marie Dolan, Mountaineers Books; May 1, 2003
4. History Link article, White Center — Thumbnail History, Essay 8616, By Ron Richardson, July 23, 2008

Documents related to Roxhill Bog

Roxhill Park Bog system map

A system map of Roxhill Park’s bog cells, numbered 1-4. The cells are the roughly rectangular areas surrounded by trails on this map, toward the right hand side. The top of the map is north at SW Barton Street. Just off of the top of this map would be the Westwood Village Shopping Center. Just off of the bottom of this map is SW Roxbury Street.

This image from the Roxhill Stewardship report, showing the same area but from the east, may help you to understand which cells are which:

The area where it says “Abandonded Laterals” is cell #1, with cell #2 below that, then cell #3, then cell #4, which is largest, and turns toward the left side of the map.

Roxhill Park area storm drain maps

A system map of all the nearby storm and waste water drainage systems near Roxhill Park.

Roxhill Park Hydrologic Investigation and Recommendations Report

A study of the peatland hydrology done by King County Department of Natural Resources. Recommends further study of hydrology, development of water flow model and design of facility to control water. The report’s date is March 2000.

Roxhill Stewardship Report 2007

Starflower Foundation survey and report on the results of the 2000-2007 restoration efforts. Contains background history, description of restoration efforts, and species survey.

Roxhill May 2014 hydration report

Prepared by David Perasso of our WWRHAH Bog Committee, with our then preliminary findings.

An older version of this document from February 2014 is available here.

Letter from WWRHAH to the City of Seattle and King County

Here is the letter that was sent on Friday, March 14th, 2014 to Seattle Mayor Ed Murray, King County Executive Dow Constantine; Seattle Councilmembers Jean Godden, and Sally Bagshaw, who chair the city council committees that oversee Parks and SPU; and King County Councilmembers Dave Upthegrove and Rod Dembowski, who chair their county committee counterparts; and it was also CC’d to City Councilmember Tom Rasmussen, who is our de facto District 1 representative at the moment, and County Councilmember Joe McDermott, our County District 8 representative.

Hello all,

I’m writing today from the Westwood-Roxhill-Arbor Heights Community Council (WWRHAH) in West Seattle, about the following, which is a possible multi-neighborhood Seattle Parks and Public Utilities issue, with a possible County impact:

We have been, over the past year, pursuing and investigating various issues surrounding Roxhill Park ( in West Seattle, ranging from it having a new King County Metro Transit Hub put next to it, to it’s crime rates, to a host of other problems. In the process of researching all of this, we gradually began to get more and more people attending our meetings with backgrounds and careers in ecology, forestry, and other environmental sciences, due to the unique character of this park and their happening to live in our WWRHAH area.

Roxhill Park is unique in being a cold water peat bog, and may be the only known publicly accessible one in the county and region. It is also a wetland and part of the headwaters of Longfellow Creek watershed: (very long web address to

Many people believed that the watershed’s restoration with Roxhill Park was completed. It turns out that this is not completely accurate, and the previous work done may in fact have caused other problems of a possible rise in flooding in other parts of West Seattle due to it’s incomplete nature. In short:

  • The bog’s water levels are too low.
  • The bog’s water levels fluctuate too much.
  • The reduced water levels could eventually cause the destruction of the natural peat base, which may be irreversible.
  • The most likely cause: a storm water drainage system which may be acting as a French drain surrounding the park is draining the bog.
  • We can’t be positive without a full hydrological study, but it’s highly likely that this is the cause.
  • The current condition of the bog and park may be contributing to periodic flooding north along the Delridge corridor, all the way to the North Delridge neighborhood.

We’re mailing today to inform you of this and to ask for your support in the investigation of this with the very skilled members of our “Bog Committee”. We initially believed this would be a matter to be pursued through a grant of some sort through the City’s Department of Neighborhoods, but the more our people dug into this, it began to appear to be a general SPU and/or Parks issue. It may be a necessity to address this, versus a “nice to have” scenario better suited for the city’s competitive neighborhood grant process.

If our team’s early assessment is correct, a coffee dam (sort of a water retaining system) would be required to be placed inside of the perimeter of the existing “French drain” system. This would allow rain water, standing water, and natural storm water run off to be retained more appropriately in the bog year round, while still allowing the existing drainage to continue outside of that, protecting the recreational park areas we have put a lot of restoration and project money into over the years, and protecting the urban neighbors of the Roxhill Bog: Daystar Retirement Village, Westwood Village Shopping Area, Roxhill Elementary School, a SHAG retirement building, a complex of low-income housing, and various single family homes.

To get to that point — if our early assessment is correct — would require the following four steps:

1.  Develop a new park hydrology model
2. Design hardware to go into the ground to keep the water in the bog
3. The building and installation of it all
4. Follow up study to make sure it’s working

Parts 1 and 4 could take up to two years each, from our estimation. Parts 2 and 3 may be expensive, but this could have a broadly positive impact in the areas of:

  • Restoring this unique location to it’s natural environmental state
  • Educational opportunities for city schools with a hydrated peat bog; there is no other like it anywhere nearby
  • Possible local mitigation of storm water run off, which may aid on the city and county level with Federal concerns on that subject
  • Crime prevention, as we have seen and reported many documented cases of public drunkenness, open air drug consumption, and illegal camping in the unnaturally dried out peat bog areas

Thank you,

Joe Szilagyi
Secretary, Westwood-Roxhill-Arbor Heights Community Council

Project media coverage

Please let us know if you have more information about this.

Again, if you have or know of any information related to this work in progress, please e-mail any details you know to, or come to one of our regular meetings.

Page last updated on March 17, 2014