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Great news for gardeners

The governor recently signed a bill allowing homeowners to use rain barrels to collect rainwater

By Carol O’Meara

There’s a saying in the West that “whiskey’s for drinking and water’s for fighting.” With every drop of water regulated by water rights and by interstate and international treaties, rolling out a rain barrel meant running afoul of the law. But that’s changing now that Gov. John Hickenlooper signed House Bill HB16-1005 on May 12, which allows people to use rain barrels at home as a water-conservation effort.

Collect the water in a watering can for use in the garden. (Photo by DJ Taylor)
Collect the water in a watering can for use in the garden. (Photo by DJ Taylor)

A rain barrel is a simple means of collecting and holding fresh water from rooftops. Technically, Colorado water law doesn’t state that a barrel is illegal, but it does say you have to have water rights in order to catch and store water in any way. So getting the bill passed is good news for gardeners.

“It’s very good for people who have no water rights for outside of their house, like in mountain communities where there’s a higher concentration of household wells with no permit for use on anything outdoors,” says Irene Shonle, director of Colorado State University Extension in Gilpin County. “I’m ecstatic about it, because for years I’ve been the bad-news messenger for people who weren’t aware of water law—that they weren’t even allowed to water a flower pot on their deck with water they captured themselves. Now they can have lots of pots.”

Attach a hose to a rain barrel’s spigot. (Photo by DJ Taylor)
Attach a hose to a rain barrel’s spigot. (Photo by DJ Taylor)

Coloradans are taking to rain barrels like ducks to water. If you’re thinking of attaching one to your downspout, here’s what you need to know: You’re allowed up to two barrels for a combined total of 110 gallons of captured water. Barrels are approved for both single-family households and multifamily residences with four or fewer units.

For those with a huge yard, a barrel or two may not have much impact, Shonle says, but the water could be used for potted plants, small gardens, compost piles, ornamental ponds and birdbaths, rinsing tools and equipment, and on plants that enjoy a bit more water than an irrigation system supplies. Capturing water from a downspout also helps manage runoff and erosion that can occur from a heavy, hard rain.

“When installing a rain barrel, the first things you need are gutters and downspouts, which not everyone has,” Shonle says. “The second thing is to figure out which part of the roof you’ll collect water from. You probably know which downspout really gushes during rain. Put the barrel there.” But double-check how the barrel looks in that location so you don’t create an eyesore.

For more info, visit the CSU Extension fact sheet at water-collection-colorado-6-707.

Rain Barrel Requirements

Photo by Kirych
Photo by Kirych

All rain barrels are required to have a lid so they don’t become a mosquito breeding ground. Water collected in rain barrels is not potable, meaning it’s not suitable for cooking, drinking or using on vegetables and fruit that you eat. Because the water washes off the roof, it captures particulates from the roofing materials, as well as grit, dirt and insects.

Barrels can be placed on opposite sides of the house, or side by side. If you put two barrels side by side, connect them so rain fills them simultaneously or you’ll find yourself dashing out in the middle of a storm to switch the downspout from one barrel to the other.

When filled, barrels are quite heavy, so moving them to water plants isn’t feasible. Look for rain barrels with a gauge to tell you how full they are, and with a spout at the bottom so you can attach a hose to them.

Place the barrel on an elevated, stable, flat surface so that a garden hose can easily draw water from the spigot for watering plants. Alternatively, siphon systems will pull water from a barrel. Make sure the elevated platform can hold the barrel’s weight, up to 1,000 pounds for 110 gallons. Concrete cinder blocks are often used for a platform. Level the blocks to prevent the barrel from tipping over, especially if the area has foot traffic or if children and pets play nearby.

Use a filter screen to sift debris like leaves and twigs from the water, and clean the screen often. Make sure the lid is properly secured to keep children, small animals and mosquitoes out. Bacillus thuringiensis (Bt)—a soil bacterium in mosquito dunks placed in ponds and water features to control mosquito breeding—works well in rain barrels, too.

You’re required to empty your rain barrel every month. Keep it out of direct sunlight to reduce algae, and clean it once a year.


How to Install a Rain Barrel

  • A sturdy, elevated base made of concrete blocks, bricks or wood
  • A rain barrel with a filter screen and spigot
  • A metal bracket
  • A hacksaw
  • Screws or PVC cement
  • A downspout elbow
  • A downspout diverter kit
  • A hose to attach to the rain barrel spigot
Installation Illustration courtesy
Installation Illustration courtesy

1. Construct a stable elevated base for your rain barrel by a downspout near your garden. The base should be high enough that water will flow freely from the barrel due to gravity. Place the barrel on the base.

2. Secure the downspout to the house with a metal bracket.

3. Cut the downspout with a hacksaw in two places—at least 4 inches above the top of your rain barrel and a few inches above the ground. Remember to account for the length of the downspout elbow and the raised base the barrel sits on. Save the removed portion of your downspout if you want to reconnect it over the winter.

4. Use steel wool to buff the rough edges of the downspout’s cut metal areas.

5. Attach the downspout elbow with screws or PVC cement.

6. Divert barrel overflow away from your foundation, walkways and neighboring property by using a downspout diverter or by digging a ground channel.