Taylor 28
Landscape Performance Benefits
Environmental
- Sequesters 1,648 lbs of carbon annually in 40 newly planted trees on a site previously devoid of trees. As the trees grow, carbon sequestration will increase.
- Eliminates potable water use for landscape irrigation (onsite and right-of-way) and uses harvested rainwater in non-residential toilets, saving up to 122,000 gals annually.
- Infiltrates all runoff generated on both the site and the public-realm pedestrian space, resulting in zero discharge to the combined sewer system for up to a 25-year storm event.
- Transformed 20 feet of excess street width into a 38-ft wide, 15,000 sf pedestrian plaza, setting the design standard for all of Taylor Avenue.
At a Glance
Designer
Mithun
Project Type
Multi-family residence
RetailFormer Land Use
Greyfield
Location
100 Taylor Ave N
Seattle, Washington 98109
Map itClimate Zone
Warm-summer Mediterranean
Size
3.7 acres
Budget
$38 million (building and site)
Completion Date
2009
Taylor 28 ushers in a new era of vitality to an under-utilized urban zone. In Seattle’s urban core, more that 35% of open space is within the public right-of-way for the street network. By restoring more than 30% of a site that was devoid of trees and consisted almost entirely of impervious surfaces, this project supports a broader strategy to create livable, walkable and ecologically balanced communities that concentrate growth within urban centers.
Challenge
The project site was in an underdeveloped urban neighborhood with no clear identity and a lack of open space. The existing low-volume street was a 56-ft roadway with back-in angled parking along both sides. There was concern that increasing development in this part of the city would exacerbate problems with the combined sewer system.
Solution
Taylor 28 established the precedent for urban design in the area with the streetscape serving as a neighborhood identifier. Excess street width was converted into pedestrian-oriented open space. Designers used a combination of right-of-way rain gardens and a roof rainwater harvesting system to prevent stormwater from entering the city’s overburdened combined sewer system.
- Over 7,500 sf of asphalt was replaced by landscape areas and high albedo paving, reducing the urban heat island effect. 40 new trees further shade and cool the area.
- All runoff from the pedestrian zone is directed to one of 8 rain gardens, which vary in size from 100 sf to about 800 sf. The profile of each includes an infiltration gallery, which in some some cases extends beyond the perimeter of the planting area above.
- Two areas of permeable concrete pavement (1,000 sf total) are located along the curb edge to capture rainwater that could not flow directly into the rain gardens. This water is piped back to the rain gardens for infiltration.
- All rain falling on the building roof enters the hybrid cistern/detention tank, which meets the City’s detention requirement for a 25-year storm. Stored water is used for non-residential toilet flushing and landscape irrigation in summer.
- A “smart” irrigation system uses water stored in the cistern to irrigate all landscape areas, both onsite and in the public right-of-way.
- High-performance LED pedestrian lighting was installed within the streetscape. The design took existing exterior street lighting into account to prevent excess lighting of the space and further reduce energy use.
By using a hybrid tank to meet the City’s detention requirement, the client was able to leverage the additional cost of incorporating rainwater reuse. It was determined that the added costs (for flow sensors, filters, piping and doubled supply pipe to the non-residential toilets) would be offset by the long-term water savings.
- Collaboration among the design team members, various regulatory agencies, utilities, and the developer was key throughout the development of the conceptual plan, overall site design, and specific construction details.
- With careful planning and creativity, streetscape improvements can be designed around existing ROW utilities.
Project Team
Client: BRE Properties
Prime Consultant/Landscape Architect, Architect, Planner: Mithun, Inc.
Building Envelope/Construction Administration: Cross 2 Design Group
General Contractor: Compass General Construction
Role of the Landscape Architect
The landscape architect was an integrated design team member from project beginning through completion and led the coordination with the City for all streetscape and stormwater issues.
