Summary of Arizona's Water Reuse Guideline or Regulation for Centralized Non-potable Reuse
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 source water for this summary is Treated Municipal Wastewater.
- Technical basis
- Applications of centralized non-potable reuse approved for use in Arizona
- Water reuse category/type
- Additional context and definitions
- Centralized non-potable reuse 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.
In Arizona, centralized non-potable reuse The use of recycled water for centralized non-potable reuse where the water does not derive from the same site where it is to be reused. Can include, but is not limited to, toilet flushing, dust control, soil compaction, fire protection, commercial laundries, vehicle washing, street cleaning, snowmaking, and other similar uses. Excludes on-site non-potable water reuse and the use of recycled water for agriculture or landscaping. applications include toilet and urinal flushing and dust control, among others. The source of water treated municipal wastewater Treated wastewater effluent discharged from a centralized wastewater treatment plant of any size. Other terms referring to this source of water include domestic wastewater, treated wastewater effluent, reclaimed water, and treated sewage. is specified by the state as municipal wastewater. The write-up uses state terms when discussing sources or uses of water that may differ from the Regulations and End-Use Specifications Explorer's (REUSExplorer's) terms.
Technical basis
Arizona approves the use of reclaimed wastewater for centralized non-potable reuse applications including toilet and urinal flushing, fire protection, commercial air conditioning, car washing, snowmaking , dust control, soil compaction, concrete and cement mixing, materials washing and sieving and street cleaning (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 state water quality standards. The classes of reclaimed water treatment differ by the level of pathogen control and treatment requirements (refer to the table for more information). The technical basis for the removal of pathogen and chemical contaminants is not explicitly specified.
Applications of centralized non-potable reuse approved for use in Arizona
Ariz. Admin. Code § 18-11 defines the following approved centralized non-potable uses:
- Toilet and urinal flushing, fire protection systems, commercial closed loop air conditioning systems, vehicle and equipment washing and snowmaking (Class A and A+).
- Dust control, soil compaction and similar construction activities, concrete and cement mixing, materials washing and sieving and street cleaning (Class B and B+).
Water reuse category/type
The various classes of reclaimed water treatment are defined by their respective treatment requirements and applicable performance standards. The respective treatment requirements are briefly summarized for centralized non-potable reuse applications.
- For Class A+ reclaimed water, the treatment requirements are secondary treatment, filtration, nitrogen removal treatment and disinfection using “oxidants, UV light, or other agents to kill or inactivate pathogenic organisms” (Ariz. Admin. Code § 18-11). Class A+ water is not required for a specific type of direct reuse but may be used for any Class A, B, or C reuse.
- 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, nitrogen removal treatment and disinfection. Class B+ water is not required for a specific type of direct reuse but may be used any Class B reuse.
- For Class B reclaimed water, the treatment requirements are secondary treatment and disinfection.
Additional context and definitions
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+, A, B+ and B requirements apply to the direct reuse of reclaimed water.
Centralized non-potable reuse specifications
Summary of Arizona's Centralized Non-potable Reuse Specifications
| Recycled Water Class/Category | Source Water Type | Water Quality Parameter | Specification | Sampling/Monitoring Requirements (Frequency of monitoring; site/ location of sample; quantification methods)* |
|---|---|---|---|---|
|
Class A+ reclaimed water (toilet and urinal flushing, fire protection systems, commercial closed loop air conditioning systems, vehicle and equipment washing and snowmaking) |
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 |
||
|
Total nitrogen |
<10 mg/L (5-sample geometric mean) |
Measured in a reclaimed water sample |
||
|
Enteric virusa |
No detectable enteric virus in 4 of last 7 monthly samples |
Monthly sampling |
||
|
Class A reclaimed water (toilet and urinal flushing, fire protection systems, commercial closed loop air conditioning systems, vehicle and equipment washing and snowmaking) |
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 (Dust control, soil compaction and similar construction activities, concrete and cement mixing, materials washing and sieving and street cleaning) |
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 |
|
Total nitrogen |
<10 mg/L (5-sample geometric mean) |
Measured in a reclaimed water sample |
||
|
Class B reclaimed water (dust control, soil compaction and similar construction activities, concrete and cement mixing, materials washing and sieving and street cleaning) |
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 |
Source = 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 centralized non-potable reuse were found for Arizona.
References:
Clean Water Act, 33 U.S.C. §§ 1251 et seq.
Department of Environmental Quality - 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.