At last, the city of Los Angeles is enacting new environmental rules for landscaping. One aspect of these new rules deals with run-off. Previously homeowners were required to eliminate rainwater via gutters, downspouts, and drains to the street, where it would flow into storm drains and down to the ocean. Run-off carries vast quantities of dog faeces and street pollutants to our beaches and marine habitats. The new rules require that water is retained on the property where possible and allowed to percolate through the soil and into our aquifers. Dry wells (large perforated tanks buried in the soil can be installed for this purpose. However, if the soil is sandy a low berm will be sufficient to hold the water while it sinks into the ground. You can also dig a pit in sandy soil and fill it with broken concrete, gravel, etc. Direct water from the downspouts to this area and the water will percolate down. The pit can be covered with pebbles for appearance.
California, although often dry, sometimes is blessed with plentiful rainfall and before the land was paved over much of this rainfall was absorbed through the soil and into the aquifers. With paving came run-off and drains, directing the water to the sea. Now we have diminished aquifers and a huge thirst. The above drawing shows how you can help augment our water supply.