The History around rain harvesting is rich with human ingenuity. Every culture has developed some method of capturing rainwater – from India, to Greece, to Machu Picchu, Peru. Rainwater collection systems have been as simple as a banana leaf to a coconut or as elaborate as an underground cistern network for an entire fort or town. The practice of harvesting rainwater dates back at least 3,000 years. History has finally caught up to Colorado. Colorado law makers legalized rain barrels on August 10^th, 2016.  

Colorado Rules help remind everyone that water is very precious in Colorado, and it is owned by users downstream. Rain that lands on a rooftop is a property right that is owned by someone downstream.  Every drop counts, and water rights holders depend upon the runoff from snowmelt and rainfall.

The arid west is unique when it comes to managing water. The use of water is governed by what is known as the prior appropriation doctrine. This doctrine of water allocation controls who uses water, how much water may be used, the types of uses allowed, and when those waters can be used. Understanding the water laws can provide valuable insight into the way water is shared in Colorado.

After a couple of attempts at the state capital, House Bill 16-1005 was passed in 2016.  It is now legal to capture rainwater at your house.  For rain barrels to be legal in Colorado, downstream water rights owners must still be able to use their water rights.  To guarantee that the captured rainwater will not change the flows in the river, there are a few guidelines that rain barrel owners must follow:

• Anyone who lives in a house or townhouse with fewer than 4 units can use a rain barrel.
• A maximum of two rain barrels can be used at each household, and the combined storage of the two rain barrels cannot exceed 110 gallons.
• Rain barrels can only be used to capture rainwater from rooftop downspouts.
• The captured rainwater must be used on the same property from which the rainwater was captured, for only outdoor purposes.
• Rain barrel water cannot be used for drinking or other indoor water uses.
• The captured rainwater can be used for watering lawns, plants, and/or gardens.
• The capture and use of rainwater using rain barrels does not constitute a water right, and no permits are necessary.
• If a water right holder can prove that rain barrels have impacted their ability to receive the water that they are entitled to, then the State Engineer can curtail the use of individual rain barrels.
• Rain barrels need to be sealable to keep out mosquitos.
• For people on well water, there is a different set of guidelines that include a need for a collection permit. Water can be used outdoors and indoors and match the well use, and they can collect as much water as they want. 
• A homeowner’s association cannot ban the use of rain barrels; however, it can impose “reasonable” aesthetic requirements about the location and/or appearance of rain barrels.

Good practices will prolong the life of your rain barrel system and save you time and money. Like any other household appliance, rain barrels need to be inspected and cared for. Here are some recommendations:

• Rain barrels should be emptied periodically to clean out debris.
• If you plan to be away from the home for more than a week, you should disconnect your rain barrel from the downspout. A thunderstorm can easily overfill your barrel.
• Drain and disconnect during the winter. Water can freeze and crack your rain barrel. Don’t forget to adjust your gutter downspout so the water will run away from your house and not into a window well.
• Shade or cover your barrel to avoid weathering from the sun. Plastic will eventually get brittle and crack if left in direct sunlight.
• An overflow hose is a good idea. Have it drain at least 6 feet from the house.
• There are various ways to build and connect your rain barrel and each will depend on the location of a drain and individual property.  A little bit of thought and planning will help you maximize your results.

Are you Curious About How to Build, Install, and Maintain a Rain Barrel? 

Below is a summary of helpful ideas and suggestions on how to have a successful rain barrel. 

 

Colorado State Law (2016): Maximum of two 55-gal barrels, outdoor water use only, use at site where collected, no drinking, it is not a water right, avoid mosquitos. 

Be Ready: 1 inch of rain on 1,000 sq. foot roof equals 600 gallons of water.  That is 12 barrels worth of water.  Rain barrels fill up very quickly. 

Water Quality: Rain barrels are good for water conservation and also water quality. 

Location:   A full rain barrel weighs close to 480 pounds.  Make sure it is in a safe location on level ground.  Know how much water comes down your downspout.  Decide if you want it invisible or visible, left/center/right of downspout, and if you want it on the north or south side of the building. 

Materials:  Barrels can be plastic or steel and can be any size.  Conversion kits are available and easy to install but are not always the best choice.  It is good to use quality bulkhead tank fittings to attach drains, spigots, and other barrels.   

Spigot:  Drill a hole the proper size about 3” from the bottom.  Use ¾” size parts, and the spigot should be a quarter turn spigot. 

Inlet:  Drill/cut proper size on the side or top of barrel.  Good to put a cleanable screen on the inlet. 

Overflow: Drill a proper size overflow hole.  Make sure it is lower than the inlet. 

Install: Pick location and level the ground.  Use strong material to build the base.  Get the barrel into final position.  Have the spigot high enough for a bucket or hose to fit underneath.

Connect to Downspout:  There are two kinds – Split-Flow and All-Flow.  Split-Flow is when you use a diverter.  They are good for handling high flows, have a built-in overflow by using the downspout, and can disconnect from your house.  Downside - Split-Flow diverters are harder to install, you don’t get all the water, they can leak, and they can clog more.  All-Flow is when you alter your downspout so that all the water goes to the barrel.  These are easier to install, clog less, divert more water, and are good for light rains.  Downside - All-Flow systems are permanent, you cannot turn them off, and you must build an overflow system. 

Split-flow Diverters:  The ones that insert into the downspout are not the best because they clog and are not cleanable and overflow easily.  The “Y” diverter is a good one to use because it can be easily turned on and off.  There are others that flip down a spout but can be messier during big rains. 

Annual Maintenance:  Protect the plastic barrel from the sun or it will get brittle and crack.  Drain and clean at least once a year.  For the winter, disconnect and drain so that it does not freeze. 

Daily Maintenance: Check the volume in the barrel and drain it if a storm is coming. Clean the inlet screen of any gutter material.  Check for debris and leaks around the barrel.  Check the base to make sure it is still stable. 

Safety:  To avoid mosquitos, keep it dry, keep the water moving, and keep it sealed.  You can use larvicides.  Make sure it is stable and keep the water away from your foundation. 

Steve Lundt is a Senior Water Quality Scientist at Metro Water Recovery.  He has over 22 years of experience managing lakes and reservoirs in Colorado and the Pacific Northwest.  If you don’t find Steve on a boat working, you can find him on a bike path in Denver.