Water Rights within the State of Arizona, what are they?

1. Surface Water Rights

These govern the use of water from rivers, streams, and lakes.

• Doctrine of Prior Appropriation:

  
  

  Arizona follows the “first in time, first in right” principle. The first person to use water from a surface source for a beneficial use (like irrigation, municipal, or industrial use) has the senior right to continue using that amount of water.

• Permitting:

  
  

  To use surface water, you must obtain a permit from the Arizona Department of Water Resources (ADWR). Rights are quantified by amount and priority date.

• Beneficial Use:

  
  

  Water must be put to a beneficial use, or the right can be lost (forfeiture).

2. Groundwater Rights

These govern the use of water pumped from underground aquifers.

• Regulated Areas (Active Management Areas - AMAs):

  
  

  In certain parts of Arizona (like Phoenix, Tucson, Prescott, Pinal, and Santa Cruz), groundwater use is strictly regulated under the 1980 Groundwater Management Act.

  • Grandfathered Rights: Existing users as of 1980 may have rights to continue pumping.

  • Service Area Rights: Municipal water providers have rights to pump for their customers.

  • Irrigation Rights: Some lands have rights to use groundwater for irrigation.

• Unregulated Areas:

  
  

  Outside AMAs, groundwater use is generally governed by the “reasonable use” doctrine, meaning landowners can pump as much as they need for reasonable and beneficial use on their land, but this is subject to change as water scarcity increases.

3. Colorado River Water Rights

Arizona receives a significant portion of its water from the Colorado River.

• Entitlements:

  
  

  Water is allocated to the state by federal law and distributed to users through contracts, such as those with the Central Arizona Project (CAP).

• Priority:

  
  

  Some users have higher priority rights than others, which becomes important during shortages.

4. Effluent (Reclaimed Water) Rights

Treated wastewater can be reused for irrigation, industrial, or municipal purposes. Rights to use effluent are generally governed by contracts and local regulations.

5. Exempt Wells

In rural areas, property owners may drill small “exempt” wells (pumping less than 35 gallons per minute) for domestic use without a full permit, but these are still subject to registration and some restrictions.

Key Points:

• Water rights in Arizona are not automatically attached to land ownership.

• Rights can be lost if not used (“use it or lose it”).

• Water rights can be bought, sold, or transferred, but transfers are regulated.

• Disputes and changes in law are common due to water scarcity.