Native plants used in a home’s landscape require the least amount of water and offer food and shelter for beneficial insects and wildlife. By using native plants rather than a lawn, contouring the landscape, making curb cuts from the street, and building swales, homeowners can harvest an abundance of rainwater on site.
Active Rainwater Harvesting = Rain Tanks, Cisterns or Barrels
“Rainwater, the cleanest and healthiest water for our gardens,” said Laura Maher, an organic seed saver and Ventura County water saving expert, “but this wonderful water is dispersed and lost into rivers, lakes, and oceans.” Homeowners can harvest water right where they live and use the water for their fruit and veggie gardens by attaching a rain barrel to the down spout from their roof. “In California,” said Laura Maher, “homeowners can harvest up to 5,000 gallons of rainwater in a container without a permit.” Rain barrels usually hold 60 gallons, but fill quickly in a rain storm. Gutters, downspouts, and pipes can be installed from the roof to various sizes of tanks and cisterns, even placed at some distance from the house, as long as the tank inlet is at least one foot lower than the bottom of the gutter. Tanks should use screens to keep out insects and be dark colored to discourage algae.
Passive Rainwater Harvesting = Rain Gardens
Swales are recessions in the soil or low tracts of marsh land that hold water and keep organic matter on site. “By digging down six inches and using the dirt to make a berm on the downhill side,” explained Laura Maher,” we can create a swale to manage water runoff, filter pollutants, and increase rainwater infiltration.” By using mulch and cover crops, the flow of rainwater during a storm can be slowed and encouraged to percolate into the soil.
On-Site Water Reuse = Greywater
Homeowners can also divert gently used greywater from their shower, bathtub, bathroom sink, and laundry to water trees and shrubs. The Laundry-to-Landscape greywater irrigation system is the only greywater source that does not require a permit for single and dual-family homes. One caveat is greywater users must switch to plant friendly laundry soap. Salts and Boron are micro-toxins that can build up and kill their plants. One simple reuse option is using a bucket in the shower to catch the cold water before it heats up. This can often be the right amount to water patio plants and veggies or flush a toilet in an apartment.
“In conclusion,” said Laura Maher, “the cheapest way to harvest and store water is by creating swales and sculpting the landscape to keep the water on site. Active rainwater harvesting is the most expensive to install and maintain. Passive harvesting can be affordable, beautiful, and very low maintenance. Greywater reuse is the most handy when the rain isn’t falling. Greywater irrigation is especially economical in the summertime when our fruit and shade trees need the most potable water. Any way you harvest water is a good start. Keep Flowing!”