Collecting and storing rainwater

Sunset, Feb, 1992 by Lauren Bonar Swezey

RATHER THAN ALLOW rainwater to flow out through gutters and into storm drains this winter, why not save it to use in the garden? By collecting rainwater, you not only get a clean, free source of water for irrigating plants, but also use a precious commodity that's in short supply these days.

Rainwater collected in barrels provides backup irrigation for valuable landscape plants during dry spells. Stored rainwater is also a high-quality source for house plants, seedlings, orchids, and other plants that may be sensitive to chemicals and salts found in some wells and city water supplies.

If rainwater is directly routed into the landscape as shown on page 54, even 1/4 inch of rain will give plants a deep soaking. When routed underground, water can be directed right to plant roots.

COLLECTING RAIN

IN BARRELS

Just a few inches of rain are enough to provide thousands of gallons of runoff from an average-size roof; the amount of water that you can collect is limited only by the size of your containers. Large containers can be expensive, however, and most gardeners don't have room for a huge tank.

Simpler, easy-to-install options (shown on page 52) include garbage can systems that you put together yourself and rain barrels that come ready to use. All capture water from downspouts. If a downspout is too low, or situated where you can't conveniently put a barrel, you can reroute it by adding pipe elbows and extension pieces.

You can get water out of homemade systems in a number of ways: dip it out with a bucket, suction it out with a hose, pump it with a small submersible pump, or add a spigot (manufactured barrels come with spigots).

To make a spigot that allows substantial flow (see top picture on page 52), use pipe glue to attach a 1 1/2-inch piece of 3/4-inch pipe into each end of a 1-inch ball valve. Glue a 3/4-inch male adapter over the 3/4-inch pipe on one end, and a slip-slip elbow on the opposite end. To install the spigot, use a 1-inch bit to drill a hole into the side of the barrel. Slip a 5/8-inch rubber washer over the male adapter, then push the adapter through the hole. Add another 5/8-inch washer over the end inside the barrel; secure with a nut.

If you want the barrel to drain completely, set the spigot low and place the barrel on blocks so you can get a watering can under it.

A DUAL SYSTEM

The system shown above was designed by Dave Stephens of Milpitas, California. Water collected off the front half of the roof is directed through two downspouts into an underground syste that waters the front garden; a 4-inch perforated drainpipe carries the water to plants. During dry periods, city water--applied by hose or bucket--supplements rainfall.

To make sure the stair-stepped planting beds are thoroughly watered during a moderate rain, Mr. Stephens inserts a standpipe (shown at bottom of large photograph), which forces the pipes at all levels to fill and soak the beds. To let overflow drain to the street during a drenching rain, he replaces the standpipe with a standard ABS plug drilled with about 20 3/16-inch holes.

His second system, on the side of the house, consists of three garbage cans connected by 1 1/4-inch male and female PVC pipe adapters and 1 1/2-inch no-hub couplings, with 1 1/4-inch rubber washers inside each barrel. At the bottom of each barrel, Mr. Stephens installed a brass hose adapter with a shutoff; a garden hose can then be attached to water plants by gravity.

WHERE TO BUY BARRELS

AND CONNECTORS

Hardware stores sell components for homemade systems. Here are mail-order sources for rainwater colleting equipment. Unless noted, tax and shipping charges are additional.

Gardener's Eden, Mail Order Department, Box 7307, San Francisco 94120; (800) 822-9600. Sells 35-gallon barrel with spigot; $65.

The Great American Rain Barrel Co., Inc., 90 Sanderson Ave., Dedham, Mass. 02026; (617) 329-8076. Sells 60-gallon barrel in dark green or gray with spigot, overflow fitting, drain plug, and a link kit to connect two barrels; $79.95.

Hartman Enterprises, 786 Coleman Ave., Suite L. Menlo Park, Calif. 94025; (800) 421-7246. Sells Save the Rain, a diverter that fits all metal and plastic downspouts; $9.95.

Quickconnect Barrel Kit, 4400 Falcon Ave., Long Beach, Calif. 90807; (310) 988-1938. Sells hose, clamps, and all fittings to connect two barrels; $6. Spigots cost $5 to $8. All items are postpaid.