Page 21 - 2021 SDCA Project

STORMWATER Stormwater runoff affects the Giving Garden site in problematic ways, but could be
harnessed as an opportunity. The garden property is located downhill of Cooper Lake
Road and the neighboring church building and parking area. During rain events,

concentrated flows of water originating from those hard surfaces, as well as the Giving
House and surrounding roofs and driveways, flows through the site down to the pond,
eroding the hilly landscape as it goes. The water wears down the garden beds and
mulch pathways, and carries particulates that impact the water quality of the pond.

SDCA proposes interventions to collect, filter, and channel the runoff, dissipating its
erosive force and distributing it to crops for irrigation.

We identified stormwater hotspots where runoff currently causes erosion and ponding
issues. We propose installing several rain gardens (“bioretention”) strategically
positioned to capture water in the most runoff-prone portions of the site. The rain
gardens help to dissipate the velocity of the runoff, reduce its volume via soil infiltration,

and filter out pollutants. Overflow from the bioretention areas is then either piped to a
safe discharge point, or routed to the garden rows and food forest in irrigation channels.
These can take the form of tiled troughs (“rills”), or earthen swales. In this way, the
stormwater can be distributed as a resource for the garden.

Overflow Drain

10’ 10’
Planting Area
Rain Garden Path

Section: This illustration depicts the condition marked by the red

section cut on the stormwater plan. For more information about

bioretention, refer to page 63.

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