Sun House System's Rain Harvest Solutions crew installs rain barrel systems on Littleton homes. That means the gutter and downspout hookup, a first-flush filter, lidded barrels, an overflow that keeps water off your foundation, and a hose or drip line out to the beds.
Before we talk hardware, here is the rule that decides what you can put in.
The rule on Littleton city water
If your house is on city water, Colorado lets you collect roof water in no more than 2 rain barrels, 110 gallons combined. The water has to come off your rooftop, and you use it outdoors on the same property. In practice that means your lawn and garden. No permit is needed for that setup.
The barrels need sealable lids and have to sit aboveground. Fill them and use them as often as it rains. The 110 gallons is a cap on storage, not a yearly total.
Untreated roof water is not drinking water. Don't plumb it into the house.
What about a big tank? Larger storage is only possible through a well-based permit. The property has to have an exempt or small-capacity well, or qualify for one, and you file DWR form GWS-78 and get the permit before collecting anything beyond the barrel allowance. If the water system serving your house supplies more than 3 dwellings, that route is closed. A city tap serves a lot more than 3 homes. So for most Littleton houses, 2 barrels is the legal ceiling.
The full rundown, with the statutes, is on our Colorado rain law page (https://sunhousesystem.com/co-rain-law). We're installers, not the Division of Water Resources. Read this as orientation, not legal advice.
What we put in on a Littleton house
The barrels are the easy part. Most of the work is getting clean water into them and back out where you need it.
Gutter and downspout check. If a run sags or drains toward the foundation, you'll hear about it before we hang anything on it.
A first-flush diverter or pre-filter, so the first dirty rinse off the shingles skips the barrel. CSU Extension recommends one. The law doesn't require it.
Two lidded barrels, 110 gallons total, set on a solid, level base.
Overflow piped away from the house for when the barrels fill up mid-storm.
A spigot and hose, or a short drip line to beds and young trees. Gravity handles most yards. If you want a small pump, we'll look at it on site.
Placement your HOA can live with. In Colorado an association can't ban barrels that follow the law, but it can set reasonable rules about where they sit and what color they are. We plan for that before install day, not after a letter shows up.
Front Range winters split barrels and fittings that are left full. We show you how to drain and disconnect before the hard freezes, and we set up the hookup so that's a quick job.
If you want to see how the pieces fit together, or what else we install, the rainwater harvesting page (https://sunhousesystem.com/rainwater-harvesting) covers it.
If you have a well, or want more than 110 gallons
If your property has an exempt or small-capacity well, or might qualify for one, more storage can be possible. The order matters:
1. Confirm the well's status with DWR.
2. If the well was never registered, register it (form GWS-12).
3. Apply for the rooftop precipitation collection permit on form GWS-78, and wait for it to be issued before you collect more than the barrel allowance.
What you can use that water for follows your well permit. Even then, roof water isn't safe to drink without proper treatment.
We can plan a larger system for a property that qualifies. We can't issue the permit, and we won't promise DWR approves it. If you're on city water, we'll say so on the first call instead of selling you a tank you can't legally fill. For how barrels and cisterns compare, see rain barrel vs cistern (https://sunhousesystem.com/barrel-vs-cistern).
Doing it yourself
You don't need a contractor for two barrels. You can buy compliant barrels and hook them up yourself, and that's legal.
We're worth the call when the gutters are tired, the best downspout is in an awkward spot, the HOA wants the barrels out of sight from the street, or you want a drip line run across the yard. Hiring us doesn't raise the limit. It's still 2 barrels and 110 gallons.
Book a free 30-minute consult
The easiest start: book a free 30-minute consult (https://sunhousesystem.com/rainwater-harvesting) in the Online Appointments section of our rainwater page. Or call (720) 239-2882. Email works too: Hello@sunhousesystem.com.
A few things make the call go faster:
City water or a well. Tell us which.
Your address, so we can confirm we cover it.
What you want to water, say a vegetable bed or a strip of lawn by the patio.
Photos of your downspouts and the spot where you picture the barrels.
Any HOA wording about rain barrels, if you have it.
By the end of the call you'll know what fits your house and what we'd need to see on site.
Questions we get from Littleton homeowners
I'm on city water. Can I bury a big tank in the backyard instead of using barrels?
No. A buried tank isn't a rain barrel under Colorado law, and being on a city tap rules out the well-based permit. Two aboveground barrels with lids, 110 gallons combined, is the limit.
Do I need a permit for two barrels?
Not from the state, as long as the setup stays within the two-barrel, 110-gallon rule. If a job adds wiring for a pump or ties into irrigation plumbing, local building rules may come into it. We'll flag that during the consult.
Can I filter the barrel water and drink it?
Not under the two-barrel rule. It doesn't allow drinking or indoor household use at all, filtered or not. Keep it outside for the lawn and garden.
My HOA says rain barrels aren't allowed. Is that the end of it?
Usually not. Colorado law says an HOA can't ban barrels that follow the rules. It can require reasonable placement and appearance, like backyard only or a color that blends in. Send us the HOA's language and we'll plan around it. We don't file your architectural request for you, and we can't promise the committee signs off.
Is there a rebate for rain barrels in Littleton?
We don't quote rebates. Programs come and go, so ask your water provider directly.
Do you work outside Littleton?
Book a consult or call with your address and we'll tell you straight.
Sources
Colorado Division of Water Resources, Rainwater, Storm Water and Graywater (https://dwr.colorado.gov/services/water-administration/rainwater-storm-water-graywater)
CSU Extension, Rainwater Collection in Colorado (https://extension.colostate.edu/resource/rainwater-collection-in-colorado/)
DWR Well Permitting, for forms GWS-12 and GWS-78 (https://dwr.colorado.gov/services/well-permitting)
Sun House System LLC, Rain Harvest Solutions division. We install systems; DWR decides permits. Ask DWR first if you plan to store over 110 gallons.
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