Harvesting Rain Water

Millie Davenport,
Home & Garden Information Center

Managing stormwater runoff is one of the principles for creating an environmentally sound “Carolina Yard”. Stormwater picks up pollutants as it travels over impervious surfaces. These pollutants can then end up in our waterways. A 1” rain falling on a 1,000 square foot roof will generate a total of 623 gallons of runoff. A great way to manage this runoff is by harvesting it with rain barrels. Water collected in rain barrels can then be used to water flowerbeds, wash the dog, wash the car or boat, fill the birdbath, irrigate the lawn, and much more.

Rain barrels range in size from 55 to 60 gallons. There are various types of rain barrels available for purchase ranging in price from $50 to $300. Rain barrels can be put together easily and inexpensively. To build your own you will need a 55 to 60-gallon food-grade barrel. Food-grade barrels are often found at local feed supply stores. Use a mixture of 2 teaspoons of castile soap and 2 teaspoons of lemon juice or vinegar per gallon of water to remove any odors from the barrel. Directions for putting together the rain barrel will vary depending on which type of barrel you use. Detailed directions for designing rain barrels can be found at http://www.clemson.edu/public/carolinaclear.

Here are a few routine things to remember to do to keep your rain barrel working properly.

  1. Try not to let water sit in the barrel for more than a week.
  2. Clean gutters at least twice a year, more often if you have trees.
  3. Completely empty and rinse your barrel at least once a year.
  4. Check for leaks at all fixtures.
  5. Check and clear down spout elbows.
  6. Caulk any gutter, down spout, and fixtures that may be leaking.
  7. If your barrel is a light color, consider painting it a darker color to help reduce algae growth.
  8. If your barrel is in the sun, consider relocating it to a shadier spot to help reduce algae growth and/or plant around it to provide shade.
  9. Check all screens regularly to be sure that mosquitoes cannot gain access.
  10. Clear debris on screens after heavy storms.
  11. Monitor where overflow is going. Is it causing erosion? If so, use plants or stone to prevent further erosion. Continue to direct overflow to permeable surfaces where the water will slowly infiltrate rather than run off.
  12. If there is no winter demand for water, you can store your barrel and route the rainfall away from your home and to a lawn or landscape bed area where the rainwater can infiltrate.

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This information is supplied with the understanding that no discrimination is intended and no endorsement by the Clemson University Cooperative Extension Service is implied. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all directions, precautions and restrictions that are listed.