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rainwater_toiletGlobal warming means droughts, and Americans have experienced plenty of those recently. Here is what you can do to prepare for a long hot summer:

Rain water harvesting is simply diverting the flow from downspouts to a barrel. Devices are available to divert water back to downspouts when the barrel is full.  You can collect 0.62 gallons (not 6 gallons as stated earlier – thanks Don for pointing it out)  of rainwater from one inch of rain on one sq ft of surface area. For example, Central Ohio averages 37 inches of rain yearly.  On 1,000 square feet of roof  that’s 22,200 gallons of water per year.

What to use

Industrial food-grade barrels that formerly housed such items as food oil, pickles, etc. — easily can be washed out and cleaned.

“We basically are taking something that would enter the recycle market to be ground up, and taking it out of the stream,” says Chris Luers, of Little Square Farm in Columbus. “We modify them, put a screen on top, valve in front, an outlet fitting and hose to control the flow. It’s a matter of using our resources wisely.”

Reasons to harvest rainwater

• It’s a wasted resource.

• It allows you to use “free” water for a variety of tasks.

• Rainwater contains far fewer chemicals than tap water.

• Allowing rainwater to travel through the sewer system adds costs and raises energy required for municipal systems.

* California is in its third year of drought.

* The Colorado River has run low 9 out of the last 10 years.

* By 2050, the Sierra Nevada snowpack is projected to be depleted by at least 25% because of climate change.

* Urban growth has reduced the groundwater feeding Arizona’s San Pedro River by 300%. The river already runs dry in places.

How to use collected water

• Hand-water plants.

• Attach a soaker hose to water nearby plants. Tip: Take out the pressure-reducing washer to allow more water flow.

• Keep compost bin moist.


For more information

• Little Square Farm:

• The Rainwater Harvesting Community:

• To download “Rain Barrels — A Homeowner’s Guide”:


GRAY WATER Recycling home wastewater (from laundry, dishes, and bathing) for use in toilets and gardens; works with a home purification system.

LIVING ROOF A waterproofed roof covered by a lightweight growing medium and planted with vegetation; reduces rainfall overflow that’s tost to storm drains.

RAINWATER HARVESTING Using a storage system (generally a storage tank and piping) to collect rain and pipe it to house and garden.

WATER “TIERS” A growing number of water agencies use tiered rates to discourage excessive use. They generally charge the least for a base amount – what you’d typically use indoors, for example. After that, the more water you use, the more expensive it gets.

Plants with low water needs

These superstar natives are tough and versatile, with low water needs and showy flowers


(Tecoma statu)

Glossy green foliage and large clusters of bright yellow flowers from late spring through early winter make it a showy choice for screening and for big shrub borders. In mild climates, you can prune and train this evergreen shrub, a Southwest native, as a tree to 25 ft. tall. Sunset climate zones 12, 13, 21-24; Hi, H2.


(Pensttmon eatonii)

It blooms from spring to early summer and tolerates heat. Its red, tubular blooms practically glow when backlit by the sun. Use this desert Southwest native to create a wildflower effect among agaves or grasses. A perennial, it grows 1 to 3 ft. tall. Zones 1-3, 7-13, 18-21.


(Arctostaphylos uva-uni)

Low and spreading manzanita makes a great groundcover, forming a mat of small, leathery leaves to 15 ft. wide. Small pink flowers appear in spring, followed by little red fruits that attract birds. Leaves turn red to purplish in winter. Native from Northern California north to Alaska. Zones A1-A3; i-s, 14-24.



With flowers in white and shades of blue, this family of plants is versatile (from groundcovers to compact bushes to tall shrubs); it also attracts butterflies. The C. ‘Concha’ (6 to 7 ft. tall; pictured) can tolerate some water in summer. Most varieties are native to California. Zones vary; C. ‘Concha’: zones 6-9, 14-24.


(Calu’andra calif omica)

The shrub attracts hummingbirds with its brilliant red stamens that resemble powder puffs. Use it as an accent in front of a living ocotillo fence or as a backdrop for small blue agaves. Native to Baja California, it’s a favorite with Southwest gardeners and reaches 5 ft. tall. Zones 10-24.

Raleigh harvesting on a grand scale

A federal stimulus loan/grant will be used to harvest rainwater at a dozen locations in the city of Raleigh.

The city has been approved for a loan from the Clean Water State Revolving Fund from proceeds from the American Recovery and Reinvestment Act (ARRA).

The loan request is a partnership of the City of Raleigh, Wake County and The North Carolina State University Water Quality Group. The $465,737 loan will be used for rainwater harvesting systems at nine City of Raleigh fire stations and three Wake County facilities. The loan has a zero-percent interest rate and half the loan will be forgiven.

The rainwater harvesting program will install cisterns at all the facilities and rain gardens at selected facilities. The projects will help address stormwater runoff and water quality concerns in Raleigh and will serve as demonstration and educations sites throughout the community. The NCSU Water Quality Group will assist in the design the facilities and monitor both water quality and the performance of the practices after installation.

This program will improve stormwater quality and reduce stormwater volumes to the drainage system to reduce flooding and erosion issues. The cisterns will provide water conservation benefits by reducing potable water usage. The Fire Department plans to utilize stormwater from the cisterns for washing fire trucks and other equipment and in some cases watering gardens and other landscaping.

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