Daylighting (streams)

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For the use of natural light in indoor illumination, see Daylighting.

In urban design and urban planning, daylighting is the redirection of a stream into an above-ground channel. Typically, the goal is to restore a stream of water to a more natural state. Daylighting is intended to improve the riparian environment for a stream which had been previously diverted into a culvert, pipe, or a drainage system.

The term also refers to the public process toward such projects. A general consensus has developed that protecting and restoring natural creeks' functions is achievable over time in an urban environment while recognizing the importance of property rights.[1]

Contents

[edit] History

Daylighting has become a publicly recognized environmental effort in Seattle, Washington, and projects to daylight Pipers and Thornton creeks, both in Seattle, are presented in detail, below. Other cities in the United States and Canada have similar projects, with slightly different timelines. Other countries, such as South Korea, also have had success daylighting.

In the course of urban development, natural streams have frequently been altered through the creation of culverts or by redirection into pipes, storm drains and sewer systems. Storm drains, if connected to local sewer systems, may overload during storms and cause unprocessed sewage to flow into nearby lakes, rivers or streams. Daylighting streams can reduce or eliminate this overflow and allows water to replenish lakes by a more natural route. Culverts and pipes usually prevent the passage of fish and, together with the loss of upstream spawning grounds, has contributed to the decline of native trout and salmon stocks. Stream restoration is a particularly effective way of increasing the integration of nature in urban areas because of their inherent beauty and because of the high level of biological diversity that accompanies riparian corridors. However, urban streams may touch multiple properties so the process of daylighting is politically complex and requires a concerted community effort. Landowners individual concerns about flood control and development rights may need to be balanced with the community and environmental benefits of a daylighted stream.[2] (For example, see Madrona Creek, below, and particularly Thornton Creek.)

[edit] United States

[edit] Seattle

[edit] Origins

Seattle was settled by Europeans in the 1850s, and developed in an uneven boom through the turn of the century to c. 1910.[3] Surface runoff increased with the nearly complete removal of forest cover during this time, Lake Washington, Lake Union, and typical small post-glacial Green Lake were lowered in the 1910s. Streams were increasingly buried with post-World War II growth (1948-1964).[4] Dramatic declines in water quality of Lake Washington and other lakes in the later 1950s was partially corrected by the implementation of sewage treatment in the 1960s.[5] Popular awareness of natural environments became significant in the 1960s and 1970s, and with that came nascent ideas about daylighting.

Thornton Creek, the largest watershed within metropolitan Seattle was the first of many gradual daylighting projects. A model of an urban stream came from nearby Greenwood, south Broadview, and northeast Blue Ridge-North Beach neighborhoods, whose Pipers Creek was spared Carkeek Park by steeper geography and the early establishment of the park boundaries (1926-1929), despite initial opposition by city government.[6] Since 1990 and earlier,[7] years of hard work by neighbors and volunteers have brought salmon back to Pipers Creek after there were none for 50 years. Along with abruptly high volume during storm runoff and resulting turbidity, water quality is the remaining big issue in restoring salmon.[8] Partly following the successes with daylighting Thornton Creek, Ravenna and surrounding neighborhoods have daylighted part of Ravenna Creek.

The results of daylighting efforts on Thornton Creek have been mixed. Heavy rains, at times, has led to flooding due to inadequate detention basins. Soap suds, oil slicks, and species kills have occurred occasionally as the visibility of streams leads to heightened awareness of stream water quality. Increased levels of fecal coliforms in Thornton Creek counts has been a recurring problem and has been variably attributed to pets and wildlife such as grazing birds. The number of spawning coho salmon has remained modest dropping from a high of 30 to 10 in 2000.[9]

[edit] Politics and community efforts

Daylighting highlights controversies between development interests and environmental conservation. The cost to communities of daylighting streams is one example of the hidden expense associated with incremental and poorly planned development activities. This is a rationale for the somewhat-contentious notion that new developments should be required to share the expense of local stream improvements. One example of this sort of political wrangling was a Seattle ballot initiative entitled, "Save Seattle Creeks," which achieved sufficient numbers of voter signatures in February 2003 to be placed on the September ballot. However, the initiative never went before voters as it was rejected by city government and development interests in a jurisdictional battle (July 2003).[10]

Building on gradual successes in restoration, activist neighbors initiated and have had some success working with the City of Seattle and developers over years toward daylighting parts of the buried Thornton Creek.[11] Organizations of citizens have cleaned up adjacent wetlands, educated the public about stream health and quality of neighborhood life, and rallied to bring more of the creek to daylight. Public utilities and parks departments have helped restore wetlands and ponds. Many restoration projects in Seattle have been in some way connected to or inspired by Thornton Creek.[12] Projects throughout the metro region are incremental, accumulating gradual successes over time. (For example, see Madrona Creek, below.)

[edit] Environmental Effects

In the Pacific Northwest, native salmon, now endangered, are iconic symbols of the Cascadia region. Even small streams can support native fish populations,[13] and daylighted streams become attractive habitat for broad ranges of diverse species. The numbers of big fish or animals are modest at best, but the results can be seen where people live. People gain understanding of the life of salmon and a living stream.[14] Resulting improvements in the quality of life in surrounding neighborhoods have had numerous side benefits, from a greater sense of community to enhanced neighborhood care.

[edit] Systems

[edit] Natural Drainage Systems

Streets and right of way for vehicles cover one quarter of Seattle's total land surface.

Natural Drainage Systems (NDS) are civil engineering features that include infiltration and slowing of stormwater flow, filtering and bio-remediation of pollutants by soils and plants, reducing impervious surfaces, using porous paving, increasing vegetation, and improving related pedestrian amenities. Natural features—open, vegetated swales, stormwater cascades, and small wetland ponds—mimic the functions of nature lost to urbanization. At the heart are plants, trees, and the deep, healthy soils that support them. All three combine to form a "living infrastructure" that, unlike pipes and vaults, increase in functional value over time.

One implementation is an S.E.A. (Street Edge Alternatives) street demonstration project in the Pipers Creek watershed, (see Pipers Creek, below). S.E.A. use innovative drainage design and landscaping instead of traditional curbs and gutters, pipes and vaults, more like the natural landscape prior to development than traditional piped systems. Impervious surfaces are reduced to 11% less than a traditional street, surface detention is provided with swales, numerous evergreen trees and shrubs are planted. The seemingly-modest change can have dramatic effect. Two years of monitoring (c. 2003) show that the SEA Street has reduced the total volume of stormwater leaving the street by 98% for a 2-year storm event (a not-uncommon severe high precipitation).[15] That reduction in abruptly high runoff flow can significantly moderate the rush of flow volume and turbidity that is so detrimental to water quality and habitat restoration for species survival—species like the iconic salmon. Unfortunately, the engineering alternatives have a relatively expensive initial price, since they are usually replacing existing structures, albeit life-limited ones. Further, conventional systems generally do not consider full cost accounting. The NDS alternatives can also provide returns on investment with amelioration of urban environments. Restoring stream habitat alone is clearly not enough to sustain the few determined but diminishing species of salmon.

Impervious surfaces such as streets, parking lots, and rooftops do not allow rainwater to seep into the soil or, indeed, go any way moderately. Consequently, the water flows quickly and in great volumes, putting a significant load on the drainage system as well as turbidity into the water. Pollutants generated by our urban activities, such as transportation, chemical landscaping, and business, are carried into streams, lakes, and Puget Sound, impacting the food chain that supports native marine fish populations—and the quality of life of humans. The sheer volume and flow rate transport non-point pollution through urban creeks. Effective solutions include the entire urban watershed, far beyond the stream channel itself.

The SEA Street breaks most of the conventions of 150 years of standard American street design. Narrow, curved streets, open drainage swales, and an abundance of diverse plants and trees welcome pedestrians as well as diverse species. Adjacent residents maintain city infrastructure in the form of street "gardens" in front of their homes, visually integrating the neighborhood along the street. The NDS (Natural Drainage Systems) united the community visually, environmentally, and socially. The 110th Cascades SEA (2002-2003) are a creek-like cascade of stair-stepped natural, seasonal pools that intercept, infiltrate, slow and filter over 21 acres of stormwater draining through the project.[16] (See Pipers Creek, below.)

[edit] Example projects

Viable, daylighted streams can exist only in intimate connection with restoration and stewardship by the neighborhoods of their watersheds in a long run, since the good health of an urban stream could not long survive carelessness or neglect.[2] With impervious surfaces having replaced most of the natural ground cover in urban environments, both the sheer volume and flow rate from unmoderated stormwater and the carrying of non-point pollution converge through urban creeks. Effective solutions include the entire urban watershed, far beyond the riparian channel itself.[15]

[edit] United States

[edit] California

[edit] New York (State)

Yonkers, New York, the fourth largest city in the state, is moving forward with the daylighting of the Saw Mill River. Now running under the Yonkers downtown, daylighting is the cornerstone of a $3.1 BILLION redevelopment program. The state government will be contributing $34 million just to the daylighting component.

[edit] Washington

[edit] Urban Seattle

[edit] Pipers Creek

Pipers Creek in the central to north Greenwood area is joined by Venema and Mohlendorph Creeks in Carkeek Park on Puget Sound. Pipers is one of the four largest streams in urban Seattle, together with Longfellow, Taylor, and Thornton creeks, (in boldface in these Urban Seattle, Metro Seattle sections). Pipers Creek drains a 1,835-acre (7 km²) watershed into Puget Sound, from a residential upper plateau that is most of the watershed, through the steep ravines of the 216 acres (0.9 km²) of Carkeek Park. The headwaters begin in the north Greenwood neighborhood.[18] Outside the park, the creek can be seen at N 90th Street between Greenwood and Palatine avenues N.

Years of hard work by neighbors and volunteers have brought salmon back to Pipers Creek, Venema, and Mohlendorph creeks in the mid 2000s after there were none for 50 years. The latter is named for the late Ted Mohlendorph, a biologist who spearheaded efforts to restore the watershed as salmon habitat.

Though still plagued by problems endemic to urban streams, Piper's Creek today is a scintillating example of the possible. Though augmented by hatchery fish, anywhere from 200 to 600 chum salmon return each November, along with a few coho in the fall and fewer occasional winter steelhead. Inspirationally, several hundred small resident cutthroat trout live in the watershed, believed to be native fish that survived decades of urban assault. Popularity of the Carkeek Park beach sees it being loved to death. An environmental learning center and programs are part of comprehensive restoration. More than four miles (6 km) of trail are maintained by neighborhood volunteers who put in 4,000 hours of work in 2003, for example. The creek waters are pretty in their impressively restored settings, but the watershed is the surrounding neighborhoods and streets, laced with petrochemicals, pesticides, fertilizers, wandering pets, and such. Along with steeply high volume during storm runoff and resulting turbidity, water quality is the remaining big issue in restoring salmon.[8]

The north fork of Pipers Creek is the site for the 110th Cascades, an S.E.A. (Street Edge Alternatives) street demonstration project (see above). The 110th Cascades are a creek-like cascade of stair-stepped natural, seasonal pools that intercept, infiltrate, slow and filter over 21 acres of stormwater draining through the project. The cascades are a part of an NDS (Natural Drainage Systems) project; together these united the community visually, environmentally, and socially, toward integrating the neighborhood as a community.[15][16]

Pipers Creek was renamed Piper's Creek by 19th century settlers;[19] the apostrophe is becoming less common today.

[edit] Taylor Creek
  • Taylor Creek flows from Deadhorse Canyon (west of Rainier Avenue S at 68th Avenue S and northwest of Skyway Park), through Lakeridge Park to Lake Washington. With volunteer effort and some city matching grants, restoration has been underway since 1971. Volunteers have planted thousands of indigenous trees and plants, removed tons of garbage, removed invasive plants, and had city help removing fish-blocking culverts and improving trails. A deer has been spotted and sightings of raccoons, opossum and birds are common. By about 2050, the area will be looking like a young version of what it looked like before being disrupted. Taylor is one of the four largest streams in urban Seattle.[9]
  • Thornton Creek, Seattle and Shoreline

[edit] Other areas
  • Neighborhoods of the Pipers Creek watershed
  • Fauntleroy Creek in the Fauntleroy neighborhood of West Seattle flows about a mile (1.6 km) from as far east as 38th Avenue SW in the modest 33 acre (130,000 m²) Fauntleroy Park at SW Barton Street, through a fish ladder at its outlet near the Fauntleroy ferry terminal (the creek drops a moderately steep 300 ft (91 m) in that one mile). Coho salmon and cutthroat trout returned as soon as barriers were removed, after concerted effort and pressure by citizen groups of activist neighbors (1989-1998). A further culvert blocks fish passage to Kilbourne Park and so on up to the headwaters in Fauntleroy Park.[20] The 98 acre (400,000 m²) watershed is about two-thirds residential development, from 1900s summer colony to post-World War II urban, with the rest natural space, primarily Fauntleroy Park.[21]
  • Longfellow Creek is one of the four largest in urban Seattle. It flows north from Roxhill Park for several miles along the valley of the Delridge neighborhood of West Seattle, turning east to reach the Duwamish Waterway via a 3,300 ft (1006 m) pipe beneath the Bethlehem Steel plant (now Nucor). Salmon returned without intervention as soon as toxic input was ended and barriers were removed, after having been extinguished for 60 years. Construction of a fish ladder at the north end of the West Seattle Golf Course will allow spawning salmon up along the fairways. Farther upstream the city has been enlarging and building more storm-detention ponds, recreation areas, and an outdoor-education center at Camp Long.[9] Three acres of open upland, wetland and wooded space just east of Chief Sealth High School in Westwood is the first daylight of Longfellow Creek. It has been the location of some plant and tree restoration since 1997.[22] After more than a decade of preparation by hundreds of neighborhood volunteers, a restoration and 4.2 mile (6.7 km) legacy trail was completed in 2004. Further improvement by removal of invasive vegetation is ongoing as native species retake hold. Blue heron and coyote can be seen. The creek first emerges at the 10,000-year-old Roxhill Bog, south of the Westwood Village shopping center.[23]
  • Madrona Creek, Seattle
    • Madrona
      Citizens of neighborhoods initiated a daylighting project in 2001, encompassing from above 38th Avenue into Lake Washington. Daylighting will return the creek to a new bed and replace the sloping lawn between Lake Washington Boulevard and Lake Washington with native plantings, and with the mouth of the creek at a restored 48,000 sq ft (4,500 m²) wetland cove on the lake. New culverts under 38th, the boulevard, and under a permeable pedestrian path will allow fish passage. Native plantings will restore about 1.5 acres (6,100 m²), with plantings three to four feet in height at three key view corridors. Planning continued through 2004, followed by design (2205) and construction (2006). The completion celebration is scheduled for spring, 2007. The $450,000 cost is funded by community-initiated grants and private donations.[24]
Citizen stewards of the creek and woods are represented by the Friends of Madrona Woods (1996). The urban forest encompasses about 9 acres (36,000 m²), largely in a couple ravines. The park area was built 1891-1893, officially no longer maintained since the 1930s with the demise of streetcars and pedestrian lifestyles.[25] Persistent efforts began (1995) with informal removal of ivy smothering trees, then invasive species like holly, laurel and blackberries, and realization that effective restoration would require comprehensive stewardship.
With a "Small and Simple" Department of Neighborhoods grant, the neighborhood started a formal effort. Neighborhood groups, planning with naturalists and landscape architects brought an effective early step rebuilding trails, promoting access and building constituency. Further priorities were protection for habitat, restoration of stream beds, rehabilitation as a natural area using native plants, and using the Madrona Woods as a setting for environmental education programs at local schools. A hired landscape architect became a team member, experimental plots were set up to test different methods for revegetating with native plants. (Plants adapt to microclimates; experimentation is required to jumpstart the otherwise very long natural processes.)
Friends of Madrona Woods earned a much larger Department of Neighborhoods matching grant in 2000, funding the creation of a Master Action Plan, and major trail restoration work. The community match for the grant was nearly 2500 hours of volunteer labor by community members and school children from St. Therese and Epiphany schools. After many decades of urban use without formal maintenance, substantial trail engineering was required. EarthCorps was contracted to do the actual construction, which included 86 steps, two landings and a bridge.
EarthCorps is a local program to foster environmental responsibility and global cooperation among young people around the world. Two thirds the Corps members come from King County and the U.S., one third are recruited from partner organizations around the world. They combine the best elements of the 1930’s Civilian Conservation Corps with those of the Peace Corps. Participants learn resource management skills by completing restoration projects throughout King County. This work has included restoring stream banks and salmon habitat, reclaiming logging roads, and building trails. They completed 30,000 hours of work in 1999 alone.
In the process of clearing, volunteers found substantial erosion in the wetland hillside, leading to a grant from a Parks Department fund to stabilize it with a water cascade of natural materials. Neighbors did a little trail-building of their own with Volunteers for Outdoor Washington and an all-day trail building workshop (February 2000). Local school children learn about restoration by working with Madrona Woods volunteers throughout the year. Work parties continue monthly through much of the year.[26]

[edit] External links

[edit] In other countries

Seoul provides one example of a major world city rediscovering its river. Mayor Lee Myung Bak, formerly a construction magnate with the Hyundai chaebol involved in burying the river during the 1960s boom, ran for office promising to daylight it, and achieved in 2005 a 5.8 km (3.6 mi) greenspace in a city without very many parks or playgrounds. Although this is not a true daylighting project -- the original seasonal and polluted stream runs below the stunningly engineered and landscaped new, artificial waterway -- the Cheonggyecheon, "pristine stream", is hugely popular, alleviating fears that opening the river would cause nearby businesses to lose customers.

The city has far to go. The project has inspired further vistas to show Seoul is not just a center of jobs, commerce, and power. The mayor has said that their goal is making Seoul a modern city—with a human face.[29]

[edit] See also

[edit] Notes and references

  1. ^ "Joint Creeks Task Force Planning Commission Public Hearing: March 22, 2006" (PDF). Creeks Task Force. Planning and Development, City of Berkeley (2006-03-22). Retrieved on 2006-06-06.
  2. ^ a b (1) "Thornton Creek Watershed". The Homewaters Project (n.d., 2006). Retrieved on 2006-04-21.
    (2) Dietrich
  3. ^ Speidel (1967, 1978)
  4. ^ Phelps
  5. ^ (1) Crowley
    (2) Wilma
  6. ^ "History [Carkeek Park"]. Seattle Parks and Recreation (2004-09-10 updated). Retrieved on 2006-06-06.
    from the files of Don Sherwood, 1916-1981, Park Historian, Don Sherwood History Files.
  7. ^ Lehner, Aponte Clark, Cameron, and Frank
  8. ^ a b Johnston
  9. ^ a b c Dietrich
  10. ^ Representative ex-post facto newspaper stories: George (27 October 2003), Mulady (18 March, 31 July), Mulady & McClure (20 June), staff 25 February, 26 May, 25 June 2003, Seattle Post-Intelligencer; Young, 20 June, 31 July 2003 (includes summary title of initiative), The Seattle Times.
    "INITIATIVE 80 -- SAVE SEATTLE CREEKS". Office of the Seattle City Clerk (2003). Retrieved on 2006-04-21. Summary title and complete text.
  11. ^ (1) Walter
    (2) "Otter and Spawning Salmon Sighted in Thornton Creek", Archive of 'The Seattle Press', The Seattle Press, 2000-10-18. Retrieved on 2006-04-21. 
    (4) Hodson
    (4) Thornton Creek Alliance staff
    (5) Mulady
  12. ^ a b Dolan & True, p. 223.
  13. ^ and small streams that are the natural spawning grounds for Pacific Salmon—the Pacific Northwest was once one of the richest fisheries in the world, second only to the Grand Banks.
  14. ^ Derek Booth, a civil engineering professor at the University of Washington who sits on an advisory board, and Diana Gale, director of Seattle Public Utilities, 2000. [Dietrich]
  15. ^ a b c (1) "Natural Drainage Systems Overview". About SPU > Drainage & Sewer System > Natural Drainage Systems. Seattle Public Utilities (2003-12-03). Retrieved on 2006-06-06.
    (2) "Street Edge Alternatives (SEA Streets) Project Index". About SPU > Drainage & Sewer System > Natural Drainage Systems. Seattle Public Utilities (n.d.). Retrieved on 2006-06-06.
  16. ^ a b (1) "Natural Drainage Systems Overview". About SPU > Drainage & Sewer System > Natural Drainage Systems. Seattle Public Utilities (2003-12-03). Retrieved on 2006-06-06.
    (2) "110th Cascade". About SPU > Drainage & Sewer System > Natural Drainage Systems. Seattle Public Utilities (2003-12-03). Retrieved on 2006-06-06.
  17. ^ Jencks, Rosa and Leonardson, Rebecca (2004). "Daylighting Islais Creek: A Feasibility Study," Water Resources Center Archives (University of California). Online version retrieved May 23, 2007.
  18. ^ "Pipers Creek". About SPU > Drainage & Sewer System. Seattle Public Utilities (2003-12-03). Retrieved on 2006-06-06.
  19. ^ Fiset
  20. ^ "fauntleroy creek facts". Fauntleroy Watershed Council, Fauntleroy Community Association. Retrieved on 2006-06-06.
  21. ^ (1) "Fauntleroy Watershed". Fauntleroy Watershed Council, Fauntleroy Community Association. Retrieved on 2006-06-06.
    (2) "History, Fauntleroy Park". Seattle Department of Parks and Recreation. Retrieved on 2006-06-06.
    (3) Phelps, pp. 216-224
  22. ^ "Native Plant Stewardship Program". 2000 and 2001 Native Plant Steward Projects, P-Z. Washington Native Plant Society (2004-10-12 revised). Retrieved on 2006-04-21.
    Thistle St. Longfellow Creek Greenspace
  23. ^ True, Kathryn (2005-08-18). "The poetry of Longfellow Creek". TRAVEL / OUTDOORS. The Seattle Times. Retrieved on 2006-04-21.
  24. ^ "Madrona Park Creek Daylighting and Restoration" (2006-01-11). Retrieved on 2006-06-06.
  25. ^ The park area was built having a streetcar from Seattle, 1891, park 1891-1893, hotel 1892, part of the Olmsted Brothers grand plan for boulevards and parks, 1903, "Mosquito Fleet" steamboat, 1909, 15 minutes to the Alaska-Yukon-Pacific Exposition (1909) on the University of Washington campus. Seattle street car lines were torn up later 1930s-1941 in parallel with Los Angeles a few years later, and other cities in the U.S. "History". Friends of Madrona Woods (2005). Retrieved on 2006-06-06.
    Referenced The Electric Trolley by Junius Rochester;
    Seattle 1900-1920 by Richard C. Berner;
    Seattle Now & Then by Paul Dorpat;
    The Lake Washington Story by Lucille McDonald;
    The Don Sherwood Files, Seattle Parks Department.
  26. ^ (1) Scott
    (2) "About EarthCorps". Retrieved on 2006-06-06.
  27. ^ "Schmitz Preserve Park Improvements". Pro Parks Project Information. Seattle Parks and Recreation (2003-06-13). Retrieved on 2006-06-06.
  28. ^ "About Us". Friends of Schmittz Park (2002). Retrieved on 2006-06-06.
  29. ^ Kirk (13 October 2005)

[edit] Bibliography

[edit] Further reading