Anne Arundel County Department of Public Works (water): backflow testing rules

Anne Arundel County Department of Public Works at a glance

When the test is due

Each assembly is tested after installation, then annually, and right after any repair. Source.

How the report is filed

A state certified tester returns the test report to county DPW within 30 days of a passing test, and failed tests within 72 hours. Source.

Approved testers

96 companies on Anne Arundel County Department of Public Works's own list, read October 6, 2026, each with a "Utility-Approved Tester" badge on its card here. The list.

Who must test

• Approved backflow preventers are required on point of use lines where needed, including residential fire suppression and lawn irrigation systems. Source.

Tester registration

• Tests must be done by testers who are both certified and approved by Anne Arundel County. Source.

Approved testers

• The county posts a voluntary list of licensed, certified plumbing companies that use its online test entry system at aacounty.org. Source.

Program

• The Anne Arundel County Department of Public Works runs a backflow prevention and cross connection program for homes, businesses and facilities on county water. Source.

From notice to filed report, the steps are the same everywhere: how a backflow test goes.

Other water utilities in Maryland

• WSSC Water
• Baltimore City Department of Public Works

Read October 7, 2026. Program page: aacounty.org.

Backflow testers near Annapolis

What the badges mean

All testers near Annapolis · Maryland roster