Environmental lands DepartmentWhat is a Rain Barrel?

Rain barrels are a very old way of collecting and using rainwater and reducing stormwater runoff. Revitalizing this old tradition is a great way to protect our lakes, rivers, and wetlands from runoff.

How Does it Work?

A rain barrel is placed underneath a shortened downspout, delivering the roof runoff into the barrel. Absent a downspout, a rain barrel can be placed under a valley of the roof. Expect to collect about a half gallon of water per square foot of roof area during a 1-inch rainfall. A typical half inch of rainfall will fill a 50 to 55 gallon barrel. Rain barrels can be made out of inexpensive 50-gallon foodgrade drums manufactured to carry juices, olives, pickles, etc. Barrels can be purchased for around ten dollars from a local beverage and wholesale distribution company.

Why Use a Rain Barrel?

Water efficiency is a great benefit of using a rain barrel. Rainwater is usually “soft” and free of dissolved minerals. Here are just a few of the ways to use collected water:

  • The untreated water is great for washing cars.
  • A soaker hose connected to a rain barrel is an easy way to water shallow-rooted plants.
  • A rain barrel is convenient for use in areas where there is not an outside spigot.
  • Use water from a rain barrel to keep a compost pile wet during the dryer summer months to promote the composting process.

Some Tips for Making a Rain Barrel:

  • Use a 50-gallon food-grade quality recycled barrel.
  • Install an overflow at the top. This is an important feature. A full barrel has the potential to spill excess water over the top causing localized erosion.
  • Consider attaching the overflow to the downspout with a spigot. The spigot can then be turned off when the barrel is full, redirecting the runoff back into the downspout.
  • Purchase a spigot with a threaded nipple, and simply twist it into the 1 inch hole.
  • Place the rain barrel on a STURDY platform to allow more clearance under the spigot. This will also increase the rate of flow when attaching a hose to the barrel’s spigot.

Safety Tips for Using a Rain Barrel:

  • Do not use barrels that have previously stored chemicals.
  • Thoroughly clean “food grade” recycled barrels.
  • Do not use collected water for drinking, cooking, bathing or watering edible plants.
  • Be sure to cover the opening with a fine screen to prevent mosquitoes from breeding in your barrel.
  • Keep the lid secure so children or animals cannot fall into the barrel.
  • Disconnect the barrel in late fall to avoid freezing and causing damage to the barrel.
  • If a moss killer has been used on the roof, let a couple of rainfall events go by before collecting the roof runoff.

Rain Barrel


To discover more about rain barrels, visit www.extension.umn.edu/waste

Univeristy of Minnesota Extension Credit

Contact Us

(218) 335-7400 DRM

Name Title Phone
Brown, Levi Environmental Director 335-7417
Harper, Jeff Water Resources Program Manager 335-7415