Capturing Rainwater
By Polly Nelson UCCE Master Gardener
When the rains came earlier this year, did you watch water run off your landscaping to the street (aka urban drool), or did it soak into your soil? What changes did you think about making during that time? What changes make sense now, in hopeful anticipation of rain later this year?
Rain barrel acquisition, creating bioswales and rain gardens, and transitioning hardscape to more porous surfaces in your landscaping are options to consider.
Most everyone has heard about purchasing rain barrels. I have five 50-gallon rain barrels placed around the four corners of my house. Hooked up to downspouts, they fill with the first inch of rain that falls each year. After that, the rain bypasses the barrel to flow out into the landscaping. Bigger barrels would store more water, but space and expense negate that option for me, and 250 gallons of water meet my needs into summer. If you decide to purchase rain barrels, make sure it has a removable lid so it can be cleaned. A faucet and a hose attachment port at the bottom make content removal easier.
My roof provides more rain than the barrels accommodate, so I have sought additional solutions. Directing downspouts to planted areas points the water to a useful destination once the rain barrels are full. Creating a bioswale channel with curves and mounds to form a dry riverbed with stones and vegetation is visually pleasing during the year, and functional in the rainy season to slow, spread, and sink water into the soil as it journeys across the landscape. Succulents fare well in my bioswale, pictured above, along with Dymondia (Dymondia margaretae) as a ground cover.
A bioswale is a conduit for water, while a rain garden is a bowl-shaped destination to capture and allow water infiltration into the soil, away from buildings. Plants that do well in rain gardens include Pacific Coast Iris (Iris douglasiana); Western Sword Fern (Polystichum munitum); Yarrow (Achillea); California Fuchsia (Epilobium canum); California Buckwheat (Eriogonium fasciculatum); Gooseberry (Ribes); and California Poppy (Eschscholzia californica).
Consider transitioning away from concrete, asphalt, and non-porous surfaces in your landscape and replace them with porous, permeable pavers and bricks. Install gravel pathways where possible to allow water to soak into the surface, capturing rainwater runoff instead of sending it to storm drains. These landscape alternatives will help us reduce the dreaded urban drool.