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DW Engineering Review | FAQs

Engineering Review

Facilities Review FAQs

Revised On: Nov. 7, 2023 - 4:10 p.m.

The following frequently asked questions and answers can help facilities learn more about the engineer review process:

A person shall not start to construct a new public water system, modify an existing facility, including an extension to an existing public water system, or make an alteration that will affect the treatment, capacity, water quality, flow, distribution, or operational performance of a public water system before receiving an Approval to Construct (ATC) from the Department. A new Public Water System (PWS) must also comply with the capacity development rules in Arizona Administrative Code (A.A.C.) R18-4-601.

There are some counties and cities that are delegated to review and issue approval certificates for public water systems | View/Download List >

Facilities owned by the federal government or the State of Arizona, those owned or operated by a delegated city or county, and those owned or operated by districts subject to the control of a city or county are not delegated and must be sent to ADEQ in Phoenix for project review.

An Arizona Registered Professional Engineer is required to seal, sign and date the plans/construction drawings,  specifications and design report. The application can be completed by the engineer or applicant and must be signed by both parties. 

If the PWS’s additions, modification, revisions, or extensions do not exceed $12,500 for material, equipment and labor, then a Registered Professional Engineer outside of Arizona may submit the application.

The review time will vary depending on work load and the completeness and quality of the application submittal. The department shall review an application and issue a decision within a licensing time frame, per Arizona Administrative Code R18-1-525 | View Time Frames >

Generally speaking, all engineering standards for drinking water distribution systems are incorporated into the Arizona Administrative Code, Title 18, Chapter 5 Bulletin 8, and Bulletin 10, Maricopa Association of Governments (MAG) Standards, Pima County Standards, AWWA and NSF International 60 and 61. 

No. Documents that are submitted as part of a complete application package shall be final plans ready for construction per A.A.C. R18-5-505(B) (1) (a).

Construction can start at any time after Approval to Construct (ATC) is received by the applicant.

Once the ATC has been issued, the applicant has 1 year to start construction. After construction has started the applicant has 3 years from the start of construction to complete construction.

If NSA results are provided to ADEQ within 1 year of original sampling event then no further sampling is required.

If NSA results are provided to ADEQ between 1 and 3 years of original sampling event then resample and provide results for total coliform bacteria, nitrates and nitrites.

If NSA results are provided to ADEQ between 3 and 5 years of original sampling event then resample and provide results for total coliform bacteria, nitrates, nitrites and Inorganic Contaminants (IOCs).

If NSA results are provided to ADEQ after 5 years of original sampling event then a complete, new NSA is required.

Treatment is required when any regulated contaminant exceeds the Maximum Contaminant Level (MCL).  This will vary depending on the type of Public Water System.

You can have your water tested at a laboratory certified by the Arizona Department of Health Services.  More information can be found on their website | Visit Site >

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