Case studies - Living Roofs in Integrated Urban Water Systems - page 159

roofs are but one component in a scheme with big objectives for stormwater
management. The cornerstone of the holistic project is the daylighting of Tryon
Creek, which has provided numerous beneits, including the restoration of a
riparian wetland corridor. Complete with lookouts, boardwalks and interpretative
water features, the new wildlife habitat area acts not only as a natural outdoor
amenity for residents of the neighborhood, but is also a major conduit for surface
low from the site, while possessing substantial ecological value as a feeder
stream for the Willamette River.
3 RAINWATER CoLLECTIoN
Stormwater is managed locally throughout the site, including small swales for
receiving runoff from roofs and the laneway between the townhomes (Liptan
2007). However, the site also operates as a neighborhood-scale stormwater man-
agement system, as on-site multiple elements feed an expansive rain garden to
the west of the site.
The system of the Tryon Creek Headwaters development site is made whole
by a variety of different and, in many cases, interdependent components. These
components are comprised of the following:
A Three housing complexes, including:
1 The Dolph Creek Townhomes - a row of townhouses to the south, along
SW Dolph Court.
2 The Headwaters Apartments - two apartment buildings to the east, along
West 30th Avenue, which are connected by a three-storey sky bridge to
allow the newly daylight creek to continue uninterrupted through the
property.
3 The Village at the Headwaters - a seniors' residence to the north of the
site, along SW Marigold Street.
B Permeable paved parking stalls and a system of low-through planter boxes to
manage runoff.
C A network of three roads (SW Dolph Court, West 30th Avenue and SW Mari-
gold Street), which were turned into green streets. These are now lined with
trees and swales, which comprise a range of 2.5-9 percent of their respective
catchment areas. The swales ill and empty with the changing of the seasons,
display pooling and running of stormwater as it passes from one part of the
system to the next.
D A restored wetland corridor that runs East-West through the site, and is cul-
verted in only two locations to allow for existing SW Dolph Court and SW
Marigold Street to run unobstructed. Excess stormwater from the creek is
retained by the rain garden of the Tryon Creek Headwaters Park.
E The three-celled, 1.5 acre rain garden of the Tryon Creek Headwaters Park,
along which is a 45 m long lume that directs creek water from the develop-
ment site to the east of West 30th Avenue. While storm simulations produced
only 72 percent stormwater detention, continued monitoring and improvements