How It Works
…from a roof with gutters.
…in barrels, both big and small, which can be plastic, fiberglass, concrete or metal, so long as it’s nonporous and smooth — even a garbage can will work.
Use collected water…
…either by filling a watering can or attaching a soaker or garden hose to water plants.
Start With a Drum
Many people make rain barrels out of inexpensive 50-gallon food-grade drums that were used to carry juices, olives, pickles, etc. Often you can find barrels for around $10 from drum and barrel suppliers.
Be sure to get a heavy-grade plastic container that won’t let in light — clear or translucent barrels can speed the growth of algae, which can clog pipes.
The water savings from using stored rainwater rather than municipal or well water can be substantial over a period of time. A rain barrel can also help reduce the amount of water that may settle around the foundation of your home.
Uses for Collected Water
- Connect to a soaker hose (with the pressure-reducing washer removed)
- Fill a watering can and hand-water plants, flower beds and gardens
- Keep your compost bin moist
- Rinse off gardening tools
How Much Rainwater Can I Collect?
A typical 1/2-inch rainfall will fill a 50- to 55- gallon barrel. Figure about a half gallon of water per square foot of roof area during a 1-inch rainfall. A 2,000-square-foot roof can collect about 1,000 gallons of water (accounting for about 20% loss from evaporation, runoff and splash).
What About Filtering?
Leaf debris, bird droppings and chemicals from roof material won’t likely be harmful to plants. Use a window screen or wire mesh to keep out debris and insects, and clean the tank periodically to remove any settling.