To ensure public drinking water systems in Arizona are designed and built to standards that provide safe, healthy water to customers, the Drinking Water Section's Technical Engineering Unit (TEU) conducts detailed reviews of system designs prior to and after the construction of public drinking water related projects throughout the state.

Prior to developing a new drinking water system or modifying an existing system, including the addition of new water sources, the applicant is required to receive an "Approval to Construct" authorization from ADEQ. After applicants have received that approval and have completed construction of the project, they are required to receive an "Approval of Construction" before they can begin operating the facility. There are timeframes which have been established for these reviews which ensures timely review and approval of each project the TEU receives.

Approval to Construct (ATC)
The TEU reviews engineering plans, specifications, and design reports for new public water system projects. In addition, the department reviews any additions or modifications to existing water systems. After completion of the review, and approval of the plans, the department will issue an ATC Certificate. Projects are reviewed for conformance to state rules and regulations (A.A.C. Title 18, Chapter 4 and Engineering Bulletin No. 10) and sound engineering practice.

Upon request by an applicant, TEU may issue a one-time extension to start or to complete construction of a project for which an ATC has been issued, as allowed by R18-5-505(E) .

For new a public water system, applicants are required to file an elementary business plan application and obtain approval from ADEQ's Capacity Development Program as required by R18-4-601 through 609 .

The capacity development process must be completed before an ATC can be issued. Newly formed water systems may also need the approval of the Arizona Corporation Commission .

If you have questions about Corporation Commission requirements and whether they apply to you, please call (602) 542-4251.

TEU also reviews new plans and modifications to existing public/semi-public swimming pool and spa projects for conformance to A.A.C. R18-5-201 through 203 and 205 through 251 .

Approval of Construction (AOC)
In order to issue an AOC Certificate, TEU reviews applications submitted for constructed projects, including Engineer's Certificate of Completion, as-built plans, specifications, and testing results. TEU reviews public drinking water projects for conformance to A.A.C. R18-4-507 through 508 and to Engineering Bulletin No. 8, and reviews public/semipublic swimming pool and spa projects for conformance to A.A.C. R18-5-204 .

Delegation Agreements
ADEQ has delegated (link to SDW Section Delegation Agreements page) some of the plan review authority and responsibility to Maricopa and Pima counties. If you are building or modifying a PWS in either of these counties, you made need to contact county authorities directly.

Variances, Exemptions, and Exclusions
The TEU may grant variances, exemptions or exclusions for water systems upon request in accordance with A.A.C. R18-4-110, 111, and 112 , respectively. The TEU may grant a variance for public/semipublic swimming pool and spa in accordance with A.A.C. R18-5-249 . While variances, exemptions, and exclusions are difficult to obtain and require a demonstration from the applicant that there is no other means for them to comply with a drinking water requirement, those systems who believe they meet all of the criteria should submit an application.

Blending Plans
Blending Plans are designs which serve to dilute water from a source that does not meet an MCL with water from a source that does so that the mixed water from both sources meets the MCL. Blending plans must be controlled through mechanical safety measures. The TEU reviews projects that use a blending plan to achieve compliance with drinking water maximum contaminant levels as per A.A.C. R18-4-221 requirements.

Consultation and Guidance
The TEU can provide informal consultation and guidance related to public drinking water projects and public/semipublic swimming pool and spa projects.

In addition, formal pre-application meetings are available. These meetings are not required for an application, but can be can be requested by contacting unit staff.

If you have a question about your plans, the review process, or would like to request a formal pre-application meeting, please contact TEU staff at (602) 771-2236.

Drinking Water Forms