Block 11, located in the Cascade Neighborhood in South Lake Union is one of the next in a series of Vulcan projects slated to be certified under Salmon-Safe Urban Standards. Designed by Runberg Architects, the proposed development at 1255 Harrison Street will add considerable punch to the fight to clean up our waterways through public private innovation.
This 384-unit, full-block development includes the installation of the second half of the Swale on Yale, a joint venture project with Seattle Public Utilities to treat stormwater before it reaches Lake Union. The newest two block-long swales will be situated on the eastern and western margins of the development, along the Pontius and Yale Avenue sides of the block. The first half of the Swale on Yale was completed in 2013, alongside Vulcan’s former property, Stack House and Supply Laundry development, one block north.
Together, the four swales will treat stormwater from 435 acres of Capitol Hill streets and sidewalks annually. The Swale on Yale project works by slowing and capturing the stormwater in a diversion vault.
A primary design goal of the project is to create pedestrian-friendly community spaces by connecting with Cascade Park to the west and aligning with the alleys of the Stackhouse apartments to the north and blocks to the south.
Green roofs will be installed on top of the new building and at the first level. All other roof drainage, not captured by one of the green roofs will be directed to one of five bioretention planters, the total size of which exceeds the optimal size for this type of best management practice according to the City of Seattle’s green stormwater infrastructure guidelines. These features provide additional stormwater management benefits beyond regulatory requirements. Other strategies of the project which contribute to meeting the Salmon-Safe standards include native drought tolerant landscape design, on-site rainwater harvesting for irrigation; high performance irrigation and water fixtures for conservation and a commitment to Integrated Pest Management in long term operations. The contractor for the project is Exxel Pacific, a Salmon-Safe Accredited Contractor.