Tucson Adopts Commercial Rainwater Harvesting Ordinance

Commercial Rainwater Harvesting Ordinance
 No. 10597
Commercial Rainwater Harvesting Development Standard,
Commercial Rainwater Harvesting Water Budget Spreadsheet

Rainwater Harvesting Workshop Presentation

On October 14, 2008, the City of Tucson Mayor and Council adopted the Commercial Rainwater Harvesting Ordinance No. 10597, the first of its kind in the country. This Ordinance takes effect June 1, 2010, and applies to new commercial construction. Facilities subject to the ordinance must meet 50% of their landscape demand using harvested rainwater, prepare a site water harvesting plan and water budget, meter outdoor water use and use irrigation controls that respond to soil moisture conditions at the site. Facilities have 3 years to establish plants before the 50% requirement must be met, and the requirement is waived during periods of drought. 

The details of how facilities will comply with the Commercial Rainwater Harvesting Ordinance are contained in the Commercial Rainwater Harvesting Development Standard, 10-03.0. The implementation date for this Development Standard is June 1, 2010. Both passive water harvesting systems (systems that passively infiltrate rainwater into soil or porous pavement for use by vegetation), and active systems (systems that store water in tanks for future distribution to beneficial uses) are addressed in the Development Standard. Applicants may choose the water harvesting system or combination of systems that is most appropriate for their site. In general, commercial sites in Tucson should be able to meet 50% of the landscape water demand using passive water harvesting systems alone.

To assist applicants in preparing the site water budget and water harvesting plan required by the Ordinance and described in the Development Standard, theCommercial Rainwater Harvesting Water Budget Spreadsheet has been prepared. This interactive excel spreadsheet can be used by applicants to help design water harvesting sub-areas of their site to enable the site as a whole to meet 50% of landscape demand using harvested rainwater. Please feel free to make use of it in site design and to provide input to City staff on how it worked for you and what changes would make it more useful. 

For assistance with technical questions, please contact:

City of Tucson Planning and Development Services
201 North Stone
Tucson, Arizona 85701
(520) 791-5550

For assistance with policy-related questions, please contact Katie Bolger, Tucson Council Ward 2, at katie.bolger@tucsonaz.gov