Water can be collected from downspouts and stored in barrels or cisterns (storage tanks) for later use, or from runoff in the landscape into drainage swales, terraces, and retention basins for more immediate use.
The benefits of harvesting rainwater include: reduced flooding, decreased erosion, prevents areas for mosquito breeding, enhances soil fertility, and lowers water utility bills.
Retention basins can be created in the area with the lowest elevation. The remainder of the landscape is developed to drain into the basin. This can be accomplished through the use of berms, terraces, drainage swales, creekbeds or drainage pipes.
Terraces with diversion swales direct water runoff from hardscapes directly to plant material.
Other steps that can be taken to conserve rainwater:
- Reduce non-permeable hardscaped areas to allow rainwater to replenish groundwater aquifers and decrease the amount of runoff in the landscape.
- Apply mulches to increase water retention, limit soil erosion, and discourage weeds from sprouting.
Resources:
www.usgbcc4.org/resources/Pictures/HarvestingTheRain.pdf
www.slocounty.ca.gov/PW/Flood_Control-Stormwater/Stormwater.htm