Sustainability in the Desert: Water Harvesting

I volunteered with the Watershed Management Group where I helped build a water havesting system in the backyard of Leslie's house. Leslie is a certified rainwater harvester and had drawn out plans to divert runoff from her front and backyards into two holding tanks. She explained that water tended to run off the sidewalk and pool in her front yard. She also had runoff from the roof that would pool near the house. The soil at her house is primarily compacted clay and there is very little infiltration. Her goal was to divert the water into two holding basins in the backyard using culverts and a rock-lined channel.
We began by digging two holding tanks, which were connected by a narrow channel.We used larger rocks to stabilize the sides of the channel and placed small rocks in the bottom to minimize erosion. Her front yard was graded to a slope of 2%, which then drained into a culvert. The culvert would divert all water collected in the front yard to a channel that ran along the fence in her backyard and into the first holding basin. Once the first holding basin fills up, the water will run through another rocklined channel into the the second holding basin. We planted various plants along the sides of the channel and basins. By building a shelf for the plant, the plant sits above the water while still allowing the roots to reach the water level.