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Tucson Rainwater Harvesting Ordinance07-08-09 | News

Tucson Rainwater Harvesting Ordinance

A Target store in Tucson is already anticipating the rain harvesting ordinance by upgrading the parking lot with tree plantings of palo verdes and sweet acacias in runoff depressions that will collect an estimated 112,200 gallons per rainstorm.

Santa Fe County, New Mexico began requiring water harvesting via cisterns or similar water-collection systems last year for new commercial and residential development.

Now, Tucson, Ariz. has passed what may well be the first municipal rainwater-harvesting ordinance in the U.S.

Tucson Water estimates that 45 percent of all water usage in its service area goes to outdoor purposes.

The Tucson rainwater-harvesting ordinance requires that all commercial development and site plans submitted after June 1, 2010 include a rainwater-harvesting plan submitted concurrently with the site and landscape plan. The plan must also include a landscape water budget that estimates the volume of water required each year for all site landscaping, and an implementation plan to show how rainwater will be harvested on site. The implementation plan will provide water metering of all onsite landscaping via a separate water meter connected to the main water supply, or via an irrigation submeter.

The ordinance further states: ?EUR??,,????'?????<

A group of developers, architects, environmentalists and ecology advocates brought together by the Tucson City Council derived the 50 percent figure.

Certain land uses within a development, however, are exempted from the 50% rainwater harvesting requirements. That would include public parks; botanical gardens; outdoor rec facilities (public or private); playing areas of golf courses; cemeteries; natural open spaces; and crop production.

A rainwater harvesting landscape water-use budget report must be submitted each year by the owner or owner?EUR??,,????'?????<

Failure to meet the 50% rainwater-harvesting requirement for landscape irrigation will constitute water wastage and constitute a code violation.

Last year, Tucson Water delivered more than 131,000 acre-feet of water, including 26,000 acre-feet of reclaimed wastewater. Local experts estimate more than 185,000 acre-feet of rainfall is available per year in Tucson.

An acre-foot is about 326,000 gallons. Picture 69 square yards a foot deep in water?EUR??,,????'?????<

Tucson?EUR??,,????'?????<

A Target store in Tucson is having a landscape architect re-landscape its 620-space parking lot in anticipation of the rainwater-harvesting ordinance. Three hundred trees are being planted in depressions in the lot, which previously had no water-capturing system. Rainfall will run from the asphalt into soil strips sloped lower than the parking spots. The project landscape architect, Eric Barrett, estimates the lot will capture roughly 112,200 gallons per rainstorm.