The Water Resources Unit

About Us

Learn more about water resources at Pima County. Visit the Pima County Water Fact Sheet

Pima County is engaged in water resources in ways you may not expect:

Land Use Authority

Through its statutory land use authority, Pima County can approve changes to density in unincorporated Pima County that increase residential and industrial water demand. The Water Resource Element of the County’s Comprehensive Plan, PimaProspers, provides the Board of Supervisors a framework to consider water use impacts before changes in land use or zoning are approved.  The building code, plumbing code and landscape codes also provide for water conservation. 

Conservation Resources

While the Sonoran Desert Conservation Plan implements landscape-level conservation, a key component is protection and restoration of riparian areas dependent on streams, springs and shallow groundwater. The biological goals of the SDCP are designed to conserve critical and sensitive wildlife habitats through the protection of in-stream flows and water quality.

Through its acquisition of conservation lands, Pima County and Pima County’s Regional Flood Control District hold surface water rights for in stream flow, stock ponds and certificated rights.  Pima County and the District also hold groundwater rights.  Board policy requires annual accounting of Pima County’s water rights. 

Reclaimed Water

The Regional Wastewater Reclamation Department operates reclamation facilities throughout Pima County serving the City Tucson, Town of Oro Valley, Town of Marana, communities in Avra Valley, Green Valley and Corona de Tucson and other areas of unincorporated Pima County. Reclaimed water is allocated to the City and Towns, with Pima County’s share used for park irrigation, riparian restoration and underground storage.

Flood Control

The Regional Flood Control District provides floodplain management throughout Pima County. Additionally, the District’s statutory authority permits construction and operation of groundwater replenishment project that enhance wildlife, recreation and riparian habitats along water course and floodplains.

Water Resources

Because water resource is all-encompassing, Pima County collaborates with municipal water providers in Pima County, as well as with local and regional partners. Among them: 

Southern Arizona Water Users Association, consisting of the largest water providers in the region, coordinates effective water resource policy and planning to reflect one voice from Southern Arizona

Arizona Department of Water Resources is the steward of Arizona water future ensuring long-term reliable water supplies to support the State of Arizona. ADWR regulates groundwater, withdrawals, monitors safe yield in the Tucson Active Management Area, implements the assured and adequate water supply rules, maintains the central repository for surface and groundwater rights and manages the state drought preparedness plan.

Bureau of Reclamation, the largest wholesaler of water in the Western United States, brings water to people and farmland. It manages the Colorado River operations delivering surface water to seven basin states including Arizona. Reclamation has announced completion of the Lower Santa Cruz River Basin Study. The study is a collaborative effort between Reclamation and local cost share partners, Southern Arizona Water Users Association, University of Arizona, the Central Arizona Water Conservation District, the Arizona Department of Water Resources, Pima Association of Governments and Cortaro-Marana Irrigation District. Pima County actively participated in the study through its membership in the Southern Arizona Water Users Association. The basin study assesses the impacts of climate change and population growth on the Lower Santa Cruz River Basin water supplies and demands. It identified four areas of concern where groundwater levels are projected to decline and identified adaptation strategies that could help offset the impacts of climate change and water demand from future population growth. The Study Summary describes the findings, goals, innovations and lessons learned.

Central Arizona Water Conservation District operates and maintains the Central Arizona Project delivering Colorado River Water to municipal and agricultural interests in Pima County. CAWCD levies a property tax to residents in Pima County to help pay the construction and operations of the Central Arizona project.

Central Arizona Groundwater Replenishment District replenishes groundwater pumped from member subdivisions in unincorporated Pima County for landowners and water providers to demonstrate an assured water supply. Do you live in a CAGRD member subdivision? If so, a CAGRD assessment is included in your property tax statement. Find out if you are in a CAGRD member subdivision by using the CAGRD Membership Locator.

Water Policy

Drought Management

Water Quality

Pima County is committed to protecting its headwaters, wetlands and intermittent and ephemeral streams. The Board of Supervisors has provided staff with policy direction per the resolutions below:

Pima County Resolutions regarding Clean Water Act