Summary of Arizona's Water Reuse Guideline or Regulation for Agriculture
This page is part of the EPA’s REUSExplorer tool, which summarizes the different state level regulations or guidelines for water reuse for a variety of sources and end-uses.
The sources of water for this summary are Treated Municipal Wastewater and Industry Process Water.
- Technical basis
- Water reuse for agriculture approved for use in Arizona
- Water reuse treatment category for agriculture
- Additional context and definitions
- Water reuse for agriculture specifications (table)
- Upcoming state law or policy
- References
- Disclaimer
This page is a summary of the state’s water reuse law or policy and is provided for informational purposes only. Please always refer to the state for the most accurate and updated information.
Technical basis
Arizona approves the use of reclaimed wastewater for the irrigation of food crops, orchards, sod farms, fiber, seed and forage crops as well as animal pasture (Ariz. Admin. Code § 18-11). The use of industrial wastewater for the production or processing of any crop used as human or animal food with application sis approved for use in Arizona on a case-by-case basis (Ariz. Admin. Code § 18-11). All applicable provisions of the Clean Water Act (CWA) (33 U.S.C. §§ 1251 et seq.), including its implementing regulations, must be met in addition to any relevant rule requirements under the Food Safety Modernization Act (FSMA) (124 Stat. 3885). Treatment requirements and performance standards are applied for the removal of microbial contaminants, chemicals and other relevant indicators related to agriculture and are summarized in the table. The technical basis for developing the specifications and/or removals of microbial contaminants, chemicals and other relevant indicators is not explicitly specified.
Water reuse for agriculture approved for use in Arizona
For reclaimed water, Ariz. Admin. Code § 18-11 defines the following approved water reuse for agriculture:
- Irrigation of food crops, spray irrigation of an orchard or vineyard (Class A)
- Surface irrigation of an orchard or vineyard (Class B)
- Irrigation of sod farms, fiber, seed, forage and similar crops (Class C)
- Silviculture (Class C)
- Irrigation of pasture for non-dairy animals (Class C)
Other reuse applications involving the use of industrial wastewater are approved on a case-by-case basis (Ariz. Admin. Code § 18-11).
Water reuse treatment category for agriculture
In Arizona, reclaimed water is defined as “water that has been treated or processed by a wastewater treatment plant” (Ariz. Admin. Code § 18-11). The class A, B and C requirements apply to the direct reuse of reclaimed water.
The various classes of reclaimed water treatment are defined by their respective treatment requirements and applicable performance standards. The respective requirements are briefly summarized regarding water reuse for agriculture (Ariz. Admin. Code § 18-11).
- For Class A reclaimed water, the treatment requirements are secondary treatment, filtration and disinfection.
- For Class B reclaimed water, the treatment requirements are secondary treatment and disinfection.
- For Class C reclaimed water, the treatment requirements are secondary treatment with or without disinfection. For Class C water, secondary treatment includes a series of wastewater stabilization ponds, including aeration. The total retention time in wastewater stabilization ponds should be at least 20 days.
In Arizona, industrial wastewater is defined as wastewater generated from an industrial process (Ariz. Admin. Code § 18-11). The respective water quality requirements are industry-specific and are determined by the Arizona Department of Environmental Quality (DEQ) on a case-by-case basis in a reclaimed water permit and specific classes are not assigned (Ariz. Admin. Code § 18-11). The Arizona DEQ is required to use best professional judgment to determine the reclaimed water quality requirements needed to protect public health and the environment for a type of direct reuse of industrial wastewater for the production or processing of any crop used as human or animal food (Ariz. Admin. Code § 18-11).
Additional context and definitions
Requirements for signage and the use of purple pipes for the conveyance of reclaimed water for reuse applications are not specified.
Arizona DEQ may allow individual permits if the end use application is not listed in the regulation and will customize the permit, using its best professional judgment, to determine the reclaimed water quality requirements needed to protect public health and the environment (Ariz. Admin. Code § 18-11-309).
Water reuse for agriculture specifications
Summary of Arizona's Water Reuse for Agriculture Specifications
| Recycled Water Class/Category (Approved Uses) | Source Water Type* | Water Quality Parameter | Specification | Sampling/Monitoring Requirements (Frequency of monitoring; site/ location of sample; quantification methods)** |
|---|---|---|---|---|
| Class A reclaimed water (food crops, spray irrigation of an orchard or vineyard) | Municipal wastewater | Turbidity | ≤2 NTU (24-hour average) ≤5 NTU (any time point) | Measured after filtration and immediately before disinfection |
| Fecal coliforms | 0 organisms/100 mL (in four of the last seven daily samples) ≤23 organisms/100 mL (single sample maximum) | Measured after disinfection and immediately before discharge to reclaimed water distribution system | ||
| Enteric virusa | No detectable enteric virus in 4 of last 7 monthly samples | Monthly sampling | ||
| Class B reclaimed water (surface irrigation of an orchard or vineyard) | Municipal wastewater | Fecal coliforms | <200 organisms/100 mL (in four of the last seven daily samples) <800 organisms/100 mL (single sample maximum) | Measured after disinfection and immediately before discharge to reclaimed water distribution system. |
| Class C reclaimed water (crops not intended for human ingestion, pasture for non-dairy animals) | Municipal wastewater | Fecal coliforms | <1,000 organisms/100 mL (in four of the last seven daily samples) <4,000 organisms/100 mL (single sample maximum) | Measured after secondary treatment and before discharge to a reclaimed water distribution system. Secondary treatment includes a series of wastewater stabilization ponds, including aeration, with or without disinfection. The total retention time in wastewater stabilization ponds is at least 20 days. |
Source= Ariz. Admin. Code § 18-11
* Specific classes or categories are not assigned for reuse applications with industry process water as the source water type (Ariz. Admin. Code § 18-11). The water quality requirements for approved applications using industry process water are industry-specific and are determined by the Arizona DEQ on a case-by-case basis in a reclaimed water permit (Ariz. Admin. Code § 18-11).
** Information about sampling and monitoring requirements such as frequency, site and quantification methods not specifically listed in the table was not explicitly specified in the State-specific regulations.
a Required if alternative treatment processes or alternative turbidity criteria are used, or reclaimed water is blended with other water to produce Class A+ or Class A reclaimed water
Upcoming state law or policy
No upcoming regulations pertaining to water reuse for agriculture were found for Arizona.
References
Clean Water Act, 33 U.S.C. §§ 1251 et seq.
Food Safety Modernization Act (FSMA), 124 Stat. 3885.
Water Quality Standards, Ariz. Admin. Code § 18-11.
Please contact us at waterreuse@epa.gov if the information on this page needs updating or if this state is updating or planning to update its laws and policies and we have not included that information on the news page.