Park Design

The Concept

“Three parks, like pearls on a string…”

Tanner Springs Park was one of three parks conceptualized by the landscape architectural firm of Peter Walker & Partners between Tenth and Eleventh Street in the River District in 1999 (presently called North Pearl District). They were to be designed for different functions yet relate to each other like “pearls on a string” in the Pearl District. The network of three parks conceptualized were Jamison Square Park for art and reflection, Tanner Springs Park for contemplation and nature viewing and The Fields Park for picnicking and sports. The firm’s direction grew out of a collaboration of the Tanner Creek and Water Feature Steering Committee and City Council, with final input from a Project Steering Committee and two public workshops. The property  was a partial donation from Hoyt Street Properties, & Portland Development Commission using Tax Increment Financing (TIF) Funds. 

Map of Tanner Springs Park: Central location between Jamison Square Park and The Fields Park in North Pearl District, From a Case History of Tanner Springs Park Photo: ©Jim Figurski via www.greenworkspc.com

The Design

Reflections through sustainability and reclamation

Tanner Springs Park was designed in 2003 by Atelier Dreiseitl (Germany), Green Works, P.C. (Portland), Portland Parks & Recreation, Portland Development Commission, and a project steering committee of public and private stakeholders. A series of community workshops were held between January and June 2003 and the park was named Tanner Springs Park in April 2005. The goal was to transform contaminated city block (.92 acres) into a healthy urban green space for contemplation and connecting with nature. A recirculating bioswale was designed to reference the historical wetlands of Couch Lake and Tanner Creek from the  years prior to industrial development. The artistic and synergistic design incorporated sustainability and  historical reclamation to make the project unique to Portland and give a strong sense of place.

Bioswale Mechanics of Tanner Springs Park
Bioswale Diagram: Mechanical details of water circulation through the park. From a Case History of Tanner Springs Park/Photo: ©Jim Figurski via www.greenworkspc.com

 

Tanner Springs Park: A Case Study for sustainable stormwater solutions by Jim Figurski, www.greenworkspc.com
Tanner Springs Park: A Case Study for sustainable stormwater solutions by Jim Figurski, www.greenworkspc.com

Sustainability: The impervious surfaces of the urban environment produce excessive precipitation runoff with pollutants and heavy metals. To mitigate this, the park collects stormwater from the sidewalks and streets surrounding it. The park is a large bioswale designed to absorb this runoff.  It is a closed system so no pollutants enter the storm water system.  The recirculating water feature attempted to demonstrate how  nature filters rainwater through cleansing sand and wetland plants then recirculating clean water through the park. Unfortunately, the sand media clogged and insufficient water was reaching the system. A direct  line pipe was installed from the pond and an a ultraviolet light component added to maintain constant water flow and reduce bacteria and algae. The plants in the lower biotope have been changed to withstand a more xeric environment caused by the excessive sand and soil composition designed to filter runoff and rain water. 

Historical  Reclamation: Located in the Willamette Valley, the park was designed to echo the habitat that existed prior to settlement and is now endangered – oak savanna and upland prairie. The naturally sloping  characteristics of the park mimic the sloping of the Willamette Valley foothills. The water runnels and pond represent the surrounding wetland of  Couch Lake and Tanner Creek, that once occupied this area. It is a heritage habitat that pays tribute to the Native Americans that lived off the land and were sustainable stewards of it.

The rail and shipping industries were an important part of Portland’s history. Train rails and Belgian blocks were reclaimed and  incorporated into the park design. The artwall, 12 feet high runs along the east edge of the park and is 180 feet long. It is composed of 368 undulating train rails, fitted with  cobalt-blue art glass. Set on end, it integrates 99 pieces of fused glass inset with images of dragonflies, spiders, amphibians, and insects. The images were hand-painted by Herbert Dreiseitl directly onto Portland glass,  then fused and melted to achieve the final effect. Belgian blocks from former ship ballasts and Portland streets create a textural walkway through the park and over waterways.

Public Use: Provide a contemplative setting, inviting for the community, to encourage stewardship and environmental education.

Maintenance: Portland Parks & Recreation maintains the park with a focus on sustainability with an adaptive management approach. Friends of Tanner Springs Park is a community group that grew out of the need for more community support for park maintenance and use. They collaborate with Portland Park and Recreation.

“Where is the real Tanner Creek?” 

The headwater for Tanner Creek is in the South West Hills and was diverted underground in the 1800s through North West Portland to the Willamette River. It runs about 20 feet below the bottom of the pond in Tanner Springs Park. Tanner Creek was named for the tannery built by pioneer Daniel Lownsdale in 1845, that  flowed into the shallow basin of Couch Lake.

Oregon Historical Society: Indicating the original flow of Tanner Creek. Taken from Tanner Creek Water Quality Characterization by Marc Peters, BES Willamette Watershed Team and Frank Wildensee, BES Science, Fish & Wildlife Program
Oregon Historical Society: Indicating the original flow of Tanner Creek. Taken from Tanner Creek Water Quality Characterization by Marc Peters, BES Willamette Watershed Team and Frank Wildensee, BES Science, Fish & Wildlife Program

Much of Portland had creeks, wetlands or seasonal flooding which the settlers altered to create dry land to build the city upon.  The adoption of the Swamp Land Act of 1850 and subsequent acts, provided a mechanism for reverting title of federally owned swampland, to states, who drained lands and altered it’s use. Under ground went streams and creeks, like Tanner Creek. While rivers, like the Willamette, were channelled.

The ecological value of wetlands was misunderstood in the 1850s. The diversion of water underground prevented the natural filtering and cleansing of water through soil and plants.  It degraded water quality, as well as altered nutrient cycling in animal and plant communities. Seventy-two years later, in 1972 the Wetland Protection Act began to reverse this damage and many creeks and rivers were day-lighted. Tanner Creek is one example of a creek that remained underground. Portland, still has permanent land and water use degradation. The good news is, the combined sewage and creek flows from the 1800s have been separated, and Tanner Creek can now flow to the Willamette, just north of Centennial Mills, albeit underground, cleaner.