Green hillsides, full reservoirs, and flowing creeks are signs that our drought woes may be subsiding (at least for now). Yet, the glorious downpours bring up another issue: stormwater runoff. Aside from what’s collected in rain barrels or absorbed into the land, much of the rain ends up flowing into the street and down the storm drain, bringing various pollutants with it straight into the Bay. How can we retain the rain in the land where it benefits plants and undergoes natural filtration of pollutants? The answer is swales!
A swale is a shallow trench that follows the contours of the land and is used to capture water. The soil removed from the trench is mounded to create a berm along the lower side of the trench. Every point along the swale should be the same height, which helps slow down the movement of the rain, spreads it out along the swale, and allows time for the rain to sink into the land. You can plant fruit trees and other perennials directly into the berms where the roots will have perfect access to the water retained by the swale.
Tenth Acre Farm has some useful information for constructing swales on residential properties. To get some in-person instruction on permaculture design elements including swales and other catchment systems, consider signing up for our upcoming permaculture workshop series “Grow More Food in Harmony with Nature” taught by gardener extraordinaire Marian Woodard. Read about the topics covered in the 8 workshop classes and sign up for individual classes or the entire series here: https://www.eventbrite.com/e/grow-more-food-home-permaculture-series-tickets-30236374811
Check out pictures from last year’s permaculture workshop series on our Flickr page. Have you already transformed your residential landscape into a permaculture garden, complete with swales? We’d love see pictures of local Contra Costa projects and explore sharing them on our Facebook or Instagram page. Email firstname.lastname@example.org with photos of your permaculture landscape.