Rain barrels reduce household water bills, improve plant health with naturally soft rainwater, and protect local waterways from polluted stormwater runoff.
Every inch of rain that falls on your roof is water you already paid for — and most of it runs straight into the storm drain. A rain barrel under a gutter downspout captures that free resource, giving you a summer-long supply of mineral-free water that plants love and the environment needs. Here is what that means for your yard, your wallet, and the watershed you live in.
How Much Money Does a Rain Barrel Actually Save?
During the peak growing season, a typical home saves about 1,300 gallons of municipal water with a rain barrel. At the national average of roughly $2 per 1,000 gallons, that works out to $5 to $10 annually — modest, but real. The bigger financial win is that garden and lawn watering accounts for 40 percent of residential water use in summer, and a barrel directly offsets that cost. During drought periods or municipal watering bans, that stored water keeps your garden alive without a single extra dollar on your bill.
Why Rainwater Is Better for Plants Than Tap Water
Tap water contains chlorine, calcium, salts, and fluoride that can build up in soil over time. Rainwater is free of those additives — it is naturally soft, highly oxygenated, and has a pH around 6, which is slightly acidic and preferable for most ornamental plants. That oxygenation encourages stronger root development and makes plants more drought-tolerant through the season. For indoor and outdoor ornamental plants, lawns, and flower beds, rain barrel water delivers what treated municipal water cannot: a composition that mirrors what plants evolved to absorb.
Environmental Benefits Beyond Your Yard
The main environmental problem rain barrels solve is stormwater runoff. In urban areas, impervious surfaces like driveways and sidewalks send rain directly into storm drains, carrying fertilizer, pesticides, oil, and sediment into local waterways. Rain barrels capture that first flush of runoff, reducing pollution and erosion. They also reduce the volume that reaches sewage treatment plants — which means less energy, fewer chemicals, and lower costs for the whole system. Overflow from the barrel can be directed to a lawn or garden bed, where it replenishes groundwater instead of flowing to a sewer.
If this sounds like something you want to set up, we have tested and compared the top picks in our guide to inexpensive rain barrels, covering models from 50 to 80 gallons that balance cost and durability.
What You Should NOT Use Rain Barrel Water For
Use it safely on ornamental plants, lawns, car washing, pet baths, birdbaths, and — if filtered — toilet flushing or pool filling. Cover the barrel to keep out mosquitoes and debris, and always fit an overflow spout or hose that directs excess water away from your home’s foundation to prevent basement flooding.
FAQs
Will a rain barrel breed mosquitoes?
Only if it is open to the air. A sealed barrel with a fine mesh screen over the opening keeps mosquitoes out completely. The screen also blocks leaves and debris from entering the water supply.
How big of a rain barrel do I need?
Standard residential barrels hold 50 to 80 gallons, which is enough for most yards during normal rainfall. The right size depends on your roof area, local rainfall, and how much you water — one 55-gallon barrel under a single downspout covers the basics.
Do I need a permit to install a rain barrel?
In most US states, residential rain barrels do not require a permit. A few states in the Mountain West and Pacific Northwest have specific volume limits or registration requirements. Check your local municipal code before installing.
References & Sources
- U.S. Environmental Protection Agency. “What is a Rain Barrel?” EPA guidance on rain barrel benefits, stormwater reduction, and water savings.