Rain barrels and reuse
Summary: A rain barrel stores roof runoff for gardens, but it fills quickly: one inch of rain on 1,000 square feet of roof is about 623 gallons. Give every barrel an overflow that discharges away from the house, and empty it before winter[1][2].
What does a rain barrel do?
A rain barrel sits under a downspout and stores roof runoff for later use on lawns, gardens or indoor plants. The EPA’s Soak Up the Rain program says collecting runoff “reduces the amount of water that flows from your property” and is “free water for use in your landscape”[1]. Many cities sell barrels to residents through annual programs, and the EPA links to state guides on installing and maintaining them.
How much can one barrel hold compared with a storm?
A common rain barrel holds about 50 to 60 gallons. The roof fills it fast: one inch of rain on 1,000 square feet of roof is about 623 gallons[2], so a 55-gallon barrel under a downspout draining 500 square feet is full after about a sixth of an inch of rain. Over a year, the same 500 square feet at Indianapolis’ average of 43.6 inches sheds about 13,585 gallons[3]. A barrel captures only a small share of that, which is why it should always have an overflow that sends excess water away from the foundation.
How should a barrel be set up?
- Put it on a level, solid base, raised enough to fit a watering can under the spigot. A full 55-gallon barrel weighs over 450 pounds.
- Use a screened inlet or diverter to keep out leaves and mosquitoes.
- Run the overflow hose at least as far from the house as the downspout would have discharged; Citizens Energy Group’s minimum is 3 feet[4].
- Empty or disconnect it before freezing weather so ice does not crack the barrel or back water up the downspout.
- Clean gutters regularly; debris from the roof ends up in the barrel.
Is rain barrel water safe for vegetables?
The EPA notes that rainwater running over a roof “can pick up pollutants such as bacteria from birds and other animals, and chemicals from roof materials”, factors to consider before using it on edible plants[1]. It points readers to university extension testing for guidance. Water the soil, not the leaves, and do not drink it.
Does a rain barrel reduce the stormwater fee?
The Indianapolis residential credit, worth up to 25% of the fee, is for approved practices such as rain gardens, on-site storage or vegetated filter strips, and needs an application[5]. Check the city manual before assuming a barrel qualifies. See Indianapolis stormwater fee.
See also
- Downspouts and the sanitary sewer
- Location and hours
- Service area
- Drainage services
- Indianapolis stormwater fee
Common questions
How fast does a rain barrel fill?
A 55-gallon barrel under 500 square feet of roof fills after roughly a sixth of an inch of rain.
Can I use rain barrel water on my garden?
Yes for most plants; the EPA advises caution with edible plants because roof runoff can carry bacteria and chemicals.
Should I empty my rain barrel in winter?
Yes. Empty or disconnect it before freezing weather.
References
- ^ a b c Soak Up the Rain: Rain Barrels. U.S. Environmental Protection Agency. Accessed 9 November 2026.
- ^ a b Rain and Precipitation (How much water falls during a storm?). U.S. Geological Survey Water Science School. Accessed 9 November 2026.
- ^ Global Historical Climatology Network daily (GHCNd), station USW00093819, Indianapolis International Airport. NOAA National Centers for Environmental Information. Accessed 9 November 2026.
- ^ Our Wastewater Correct Connect Initiative. Citizens Energy Group. Accessed 9 November 2026.
- ^ Stormwater User Rate, Payment Options and Credit Manual. City of Indianapolis (indy.gov). Accessed 9 November 2026.