Illinois backflow testing rules

Who sets the rules in Illinois

35 IAC 604.1505(b)(2).

35 IAC 604.1505(b)(4).

35 IAC 653.801 notes show it repealed; the current requirement is Part 604, Subpart O.

Sources: All community water supplies must have a cross connection control program; Former Part 653 cross-connection rule was repealed April 14, 2025

Is an annual test required?

35 IAC 604.1510(a). Mechanical devices must include physical testing.

77 IAC 890.1130(b), by a Cross-Connection Control Device Inspector (CCCDI).

77 IAC 890.1130(b).

Sources: Cross-connection control devices must be inspected at least annually by an approved inspector; Plumbing Code: RPZ, RPDA, DCA and DCDA assemblies tested before first use and at least annually

Which properties need a backflow preventer

77 IAC 890.1140(d), Illinois Plumbing Code; applies to any lawn sprinkler system, so residential irrigation is covered.

77 IAC 890.1130(d). Exempt only if looped, no non-potable or Siamese connection, 20 sprinkler heads or less, potable-quality pipe.

77 IAC 890.1130(d)(3).

77 IAC 890.1140(d); RPZ may be outside if protected from freezing or removed at season end.

Sources: Lawn sprinkler systems on potable water need an RPZ; Fire safety systems: backflow protection required except small looped potable systems

Who may do the test

35 IAC 604.1510(a) and (b). Applicants must be authorised to perform plumbing under the Illinois Plumbing License Law.

Source: Inspector must be approved by the Illinois EPA (or its designee) as a CCCDI

How the test report is filed

35 IAC 604.1510(a)(1). No deadline stated. Each device also gets a tag with test date and CCCDI name.

35 IAC 604.1505(b)(5).

Sources: Annual inspection records go to the community water supply; Water supply keeps records of all backflow preventers requiring annual testing

If a test is missed

35 IAC 604.1510(b)(3). Customer-level shutoff or fines not found.

Source: CCCDI approval can be suspended or revoked for falsified reports or willful negligence