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Islais Creek reinterpreted: An exploration of restoration designs in the urbanized context of San Francisco Lucas A. Griffith, University of California, Berkeley LA 227 Restoration of Rivers and Streams - Fall 2006. Instructor: Dr. Mark Tompkins, University of California, Berkeley
ABSTRACT: In my initial inquiry into the environmental history of the Alemany Farmers’ Market in San
Francisco, I learnt of a creek – Islais Creek, the largest watershed in the city.
I measured and analyzed an 1869 U.S. Coast Survey to establish a representative baseline for
the historical character of Islais Creek. Historically water accumulated on the shallow soils of
the San Bruno Mountains and flowed into Islais Creek I used additional maps and surveys from
the late nineteenth and early twentieth centuries to document the cultural settlement of the
watershed and further discuss land use impacts on the creek. For the past one-hundred and
fifty years urban expansion and development have severely altered the original character of
the creek and disallowed natural fluvial dynamics to persist. Currently the creek serves as the
infrastructural backbone to a combined sewer system located underground in concrete pipes
and culverts.
In this repost I developed a restoration plan informed by an opportunities and constraints
analysis of the existing conditions within the watershed. The plan gathers surface flows from
a small subwatershed adjacent to the farmers’ market site and uses the historical baseline
condition to inform creek design. I used the rational method to establish a design discharge
and discharge from the 200 acre subwatershed area and employed other standard hydrologic
and hydraulic methods to estimate appropriate channel geometry for a two year flow regime.
The restoration of Islais Creek as proposed in this report represents an exploration of
thought more than classic geomorphologic restoration; the landscape tells the story of the
creek and restores its symbolic presence in the urban environment and in the minds of the
people living and visiting the space. The proposed creek form builds an understanding of the
fluvial process, enhances our knowledge of aquatic ecosystems and ultimately enriches our
connection to place. We are restoring more than ecological systems, we are restoring our
awareness and compassion for nature.
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