Daylighting (streams)

Here Marin Creek has been daylighted.

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]

Systems

Natural drainage systems

Natural Drainage Systems (NDS) are stormwater management features that include infiltration and slowing of stormwater flow, filtering and bioremediation 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. The final constructed design reduced imperviousness, or resistance, by more than 18 percent, surface detention was provided with bioswales,(landscape elements intended to remove silt and pollution from surface runoff water), and 100 evergreen trees and 1100 shrubs were planted, according to FEMA . 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).^[2] 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.

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 (85,000 m²) of stormwater draining through the project.^[3] (See Pipers Creek, below.)

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.^[4] 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.^[2]

United States

California

• Codornices Creek and Strawberry Creek, Berkeley, California
• Islais Creek,^[5] San Francisco, California^[6]

New York (State)

Yonkers, New York, the fourth largest city in the state, broke ground on December 15, 2010 on a project to daylight of the Saw Mill River. Now running in an enclosed flume 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.

Seattle, Washington

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. 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.^[7] 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. 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 (85,000 m²) 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.^[2][3]

Pipers Creek was renamed Piper's Creek by 19th century settlers A. W. Piper and his large family;^[9] the apostrophe is becoming less common today.

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.^[10]
  • Skyway and Bryn Mawr in unincorporated King County
  • Rainier View-Lakeridge
• Thornton Creek, Seattle and Shoreline
  • Matthews Beach, where the creek flows into Lake Washington
  • Meadowbrook
  • Northgate
  • Adjacent, formerly suburban city of Shoreline; southeastern neighborhoods.

Other areas

• Neighborhoods of the Pipers Creek watershed
  • Greenwood
  • South Broadview
  • Northeast Blue Ridge
• 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.^[11] 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.^[12]
• 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 (1000 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.^[10] An area of 3 acres (12,000 m²) 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.^[13] 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.^[14]
• 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.^[15]

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.^[16] 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 1930s 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.^[17]

• Mapes Creek, accessible at Kubota Garden, flows from a ridge to Lake Washington.
  • Rainier Beach
• Puget Creek flows into the Duwamish River from Puget Park on SW Dawson Street near 19th Avenue SW, near the Delridge neighborhood of West Seattle.
  • East Delridge
  • Industrial District
• Ravenna Creek, Seattle
  • Ravenna and Ravenna-Bryant
  • The remaining watershed includes Roosevelt and parts of the University District.
  • The creek flows past the Union Bay Natural Area into Lake Washington.^[18]
• Schmitz Creek in the Alki neighborhood of West Seattle flows to the sound from Schmitz Park, SW 55th Avenue at SW Admiral Way. Apart from the paved entrance and a parking lot at the northwest corner, the park has remained essentially unchanged since its 53 acres (210,000 m²) were protected 1908-1912 from complete logging. Fragmentary old growth forest remains. Daylighting and drainage rebuilding to handle seasonal and storm flow was done 2001-2003.
  • Alki^[19] Friends of Schmittz Park are neighborhood citizen stewards of the park (and creek).^[20]

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 kilometres (3.6 mi) greenspace in a city without very many parks [citation needed] or playgrounds. Although this is not a true daylighting project—the original seasonal and polluted stream runs below [citation needed] 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.^[21]

See also

• Stream
• Subterranean river
• Water resources
• Stream restoration

Notes and references

Bibliography

Further reading

External links

• http://www.GroundworkHudsonValley.org
• http://www.SawMillRiverCoalition.org
• http://riverwiki.restorerivers.eu