Using Rain Barrels: Economics, Collection, and Distribution Realities

With summer temperatures in the 90s, gardeners think seriously about water sources. I've received many rainwater collection questions this summer.

Jeff B. wants a cistern for guilt-free vegetable garden watering during drought. Margaret K. notes Austin, TX offers a $500 rebate for rainwater systems—anything similar in Georgia? Carolyn C. in Roswell wants pros/cons of rain barrels and experiences with elaborate systems. Karen A. saw pepper barrel demos in Tampa and wants Gwinnett area info and purchases.

Economics

Southface Energy Institute calculates a 2,000 sq ft roof could yield 40,000 gallons yearly. At ~1¢/gallon (including sewer), that's $400 savings if every drop is collected.

Collection

Rainfall isn't evenly distributed—concentrated in winter/spring when gardens don't need it. Summer thunderstorms yield lots of water, but a 1-inch rain on that example roof produces 800 gallons—requiring sixteen 50-gallon drums, beyond most gardeners' capacity. Even with a single barrel, water must be screened. Master Gardener Theresa Schrum excludes leaves and pine needles easily, but pine pollen creates a goopy mess each spring.

Distribution

Commercial barrels have hose-threaded spouts near the bottom. Inexpensive food-grade barrels need a hose-threaded bung installed and sealed.

Krissy Slagle, state Master Gardener program manager, notes non-economic benefits: rainwater is soft, chlorine- and fluoride-free; reduces runoff; and fosters good citizenship by lowering municipal demand.

More Information:

• American Rainwater Catchment Systems
• Oregon Rainwater Harvesting
• Harvested Rainwater Sourcebook

Your Experiences? Gardeners also wonder about graywater from washers. My grandmother ran her washer hose into canna lilies—worked fine with endless fishing worms at the discharge spot. I tried collecting washer graywater once: filtering, storing ≤24 hours, and distributing evenly was more than I could manage.