The season’s first drops of rain release the familiar earth smell. Plants happily uncurl. If it is a wet season, kids can float paper boats down the oily gutters. Parents tell their children stories of people who thought they could swim in the concrete rivers. When the season ends plants and people get ready for seven months of dry weather.
Los Angeles is a Mediterranean climate; it rains but all at once. This periodic outburst of water led to flooding in the city’s early history. City engineers responded by designing the city to move water as quickly as possible to the ocean. The city infrastructure is extremely efficient at this. With most of L.A. being covered by impermeable surfaces, very little water is able to sink into the ground and refill the aquifers. Choosing a piece of pavement, finding a sledgehammer, and letting out some aggression would help the problem. You can also harvest the rain.
You can start harvesting rain on a small scale by buying a rain barrel or making your own. I bought a blue 55 gallon drum off of craigslist for $10. These barrels are used to transport everything from mayonnaise to paint and often end their lives in the landfill. If you reclaim one of these make sure it has only been used for food. I cut a hole in the top for rain to enter, covered it with some recycled screen to keep out debris, drilled a hole in the bottom and inserted a hose bib. I cut my downspout about halfway down and placed the barrel underneath.
To calculate how much rain you can collect, calculate the area of your roof (length x width), multiply that by the inches of rain you receive and multiply that by .623 (that converts one inch of water in one square foot to gallons). For example, if one inch of rain falls on a house with a 1,000 sq. ft. roof: 1000 x 1 x .623 = 623 gallons. Obviously, a 55 gallon barrel will fill up fast. Those looking for more storage can purchase tanks that hold several hundred gallons or even underground cisterns holding thousands of gallons. This water is then typically used for irrigation.
Harvesting rainwater reduces the need to transport water hundreds of miles to our city while reducing runoff and the pollution that accompanies it to our oceans. Any area with infrequent rainfall can benefit by collecting this precious resource.