Marin Master Gardeners
University of California
Marin Master Gardeners

Consider a Simple Water-Catchment System and Rain Garden/Bioswale Before Winter Rains Arrive

Bioswales capture rainwater, sustain plants, and prevent run-off
Bioswales capture rainwater, sustain plants, and prevent run-off

There is serious talk of an El Nino this year with a chance of a wet winter ahead for us in Marin.  Why not consider several water-wise ways to take advantage of any rain we receive.  There are simple water catchment systems that are easy to set-up to collect rain water from your roof. You can also consider a bioswale or rain garden on your property to collect and use water that would otherwise run off - an additional big benefit is turf reduction.  Raised walking paths and sunken gardens will also collect and store water for your plants. 

gutter
Simple barrel catchment
Simple barrel catchment



















Bioswale diagram
Bioswales are designed to capture runoff water using swaled drainage with gently sloped sides filled with vegetation. The water is captured in a design to maximize the time water spends in the swale to provide water for drought-tolerant, sun-tolerant native vegetation. A bioswale can be small or large depending on your needs. For example, you can build a single plant "castle and moat" design around a plant to capture and hold water - even on a slope. For more on bioswale/rain garden design for your yard, see here and here.  A UC Master Gardener slide show on sustainable gardening using rainwater harvesting with examples of simple water-catchment systems is available here.

Swlae sketch

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