Backflow Laws: Illinois
Illinois Backflow Prevention Laws, Regulations, and Compliance Requirements
Illinois operates a dual regulatory system for backflow prevention: the Illinois Environmental Protection Agency (IEPA) Title 35 regulations govern public water system cross-connection programs, while Illinois Administrative Code Title 77, Part 890, Section 890.1130 — the Illinois Plumbing Code — governs installation and testing requirements. Illinois's distinctive credential is the Cross-Connection Control Device Inspector (CCCDI), certified through the Environmental Resources Training Center at SIU-E. This guide covers the Illinois regulatory framework, the CCCDI program, and major utility programs for Chicago, suburban Chicagoland, Springfield, and other communities.
Illinois State Regulatory Framework
Illinois’s backflow prevention requirements are rooted in two complementary bodies of regulation. The Illinois Environmental Protection Agency (IEPA) administers drinking water quality standards under IEPA Title 35, Illinois Administrative Code, which requires all public water systems to have effective cross-connection control programs. The Illinois Plumbing Code (Illinois Administrative Code Title 77, Chapter I, Part 890) governs the installation, testing, and maintenance requirements for backflow prevention assemblies at the state plumbing level.
Under IEPA regulations, industries and facilities with backflow prevention devices must have those devices inspected and tested at the time of installation and at least annually thereafter. Verification of inspection must be submitted to community public water supply officials, who must ensure that appropriate inspections and maintenance of all cross-connection control devices has been performed.
The Illinois Plumbing Code at Section 890.1130 (Protection of Potable Water) requires that all reduced pressure principle (RPZ), reduced pressure detector (RPDA), double check (DCVA), and double check detector (DCDA) backflow prevention assemblies be tested and approved by a Cross-Connection Control Device Inspector (CCCDI) before initial operation, and at least annually after initial inspection. Records verifying testing and maintenance must be available at the site of the installation.
Illinois CCCDI Certification — The State-Specific Credential
Illinois’s distinctive tester credential is the Cross-Connection Control Device Inspector (CCCDI), not ASSE 5110 or ABPA. The CCCDI certification is administered through the Environmental Resources Training Center at SIU-Edwardsville (SIUE/ERTC). The CCCDI program is coordinated by IEPA’s Field Operations Services as a basic element of the water supply program, with actual training and certification primarily conducted by ERTC.
CCCDI certification requires a four-day training course addressing IEPA and IDPH rules and regulations, hands-on practice testing of different backflow devices, and proper maintenance and repair. Testing procedures include back pressure testing of double-check valves at 2 PSI and the technique of testing each check in Direction of Flow at 1 PSID. Annual one-day symposiums and one-to-two-day refresher courses are also offered.
In Illinois, the tester must be a licensed plumber in Illinois and a Certified Cross-Connection Control Device Inspector. The dual requirement — Illinois plumbing license PLUS CCCDI certification — distinguishes Illinois from states where only a standalone backflow tester credential is required. This means general contractors without an Illinois plumbing license cannot legally perform backflow testing in Illinois, even if they hold ASSE 5110 or ABPA credentials.
Chicago Municipal Exception
The City of Chicago operates under a separate municipal ordinance — the Chicago Plumbing Code — which differs from the statewide IDPH plumbing code in material, inspection, and licensing requirements. Chicago’s Cross Connection Control requirements are administered through the City of Chicago Department of Water Management. Property owners in Chicago should confirm requirements with the Chicago Department of Water Management directly, as Chicago’s local ordinance may impose requirements beyond the state baseline.
Illinois's Dual License Requirement: Plumbing License + CCCDI
Unlike most U.S. states where a standalone backflow tester certification is sufficient, Illinois requires that the tester be both a licensed plumber in Illinois AND a Certified Cross-Connection Control Device Inspector (CCCDI). This means backflow testing in Illinois must be performed by someone who has met the full requirements of both credential systems. A tester who holds only ASSE 5110 but not an Illinois plumbing license cannot legally perform testing in Illinois. Always verify both credentials before scheduling.
Major Water Purveyors in Illinois
Chicago Department of Water Management
The City of Chicago’s Department of Water Management serves Chicago and also provides water wholesale to more than 120 suburban communities. Chicago’s cross-connection control requirements are administered under the Chicago Plumbing Code ordinances. Annual testing is required for all covered assemblies. Chicago’s size and the scale of its wholesale supply relationships make it one of the most significant water systems in the Midwest for cross-connection control enforcement. Property owners in Chicago should confirm program requirements directly with the Department of Water Management.
Suburban Chicago Utilities — BSI Online Is Dominant
Across the broader Chicago metropolitan area, a large number of suburban municipalities have contracted with Backflow Solutions Inc. (BSI Online) to administer their cross-connection control programs. Communities using BSI Online include Deerfield, Glencoe, Lake Zurich, and dozens of other northern and western suburbs. Under BSI-administered programs, testers must enter results in the BSI Online tracking system at bsionline.com; notifications are sent to property owners approximately 30 days before devices are due for annual testing; and compliance letters are managed by BSI on behalf of the municipality. The Illinois plumbing code requires annual testing regardless of whether the irrigation system is currently in use — a device must be tested annually even if the irrigation system is turned off for the season.
Illinois American Water
Illinois American Water is the largest investor-owned water utility in Illinois, serving communities across the state including Peoria, Alton, Springfield (portions), and many other communities. Illinois American Water’s cross-connection control program aligns with IEPA Title 35 and the Illinois Plumbing Code. Annual testing by Illinois-licensed plumbers with CCCDI certification is required. Test verification must be submitted to Illinois American Water within their specified window.
Springfield and Central Illinois
The City of Springfield (Capital City Utilities) and surrounding central Illinois communities each operate individual cross-connection control programs. Springfield’s utility has a comprehensive program requiring annual testing for all commercial, industrial, institutional, and covered residential assemblies. Test results and maintenance records must be kept on-site and available for inspection.
Peoria, Rockford, and Other Major Illinois Cities
The Illinois American Water Peoria division, Rockford’s public utilities, Aurora, Joliet, Naperville, and other major Illinois communities each operate programs aligned with IEPA requirements. The Illinois Section of AWWA (ISAWWA) maintains a backflow information resource at stopbackflow.info that provides utility-specific guidance and regulatory references for Illinois water professionals.
Annual Testing Required Even for Inactive Irrigation Systems
Illinois municipalities and their BSI-administered programs are explicit on a frequently contested point: backflow prevention assemblies on irrigation systems must be tested annually even if the irrigation system is not in use for the season. A property owner who shuts down their irrigation system for the winter is still required to have the backflow assembly tested annually. The device must be in acceptable working condition regardless of use status.
Property Owner Compliance Summary for Illinois
Credential: Testing must be performed by an Illinois-licensed plumber who is also a Certified Cross-Connection Control Device Inspector (CCCDI). Both credentials are required.
Annual testing: All RPZ, RPDA, DCVA, and DCDA assemblies must be tested before initial operation and at least annually thereafter. Records must be available on-site.
Filing: Verification submitted to your water utility. Many suburban utilities use BSI Online — submit through bsionline.com where applicable.
Chicago: Confirm Chicago-specific requirements with the Chicago Department of Water Management.
Irrigation: Annual testing required even when irrigation system is not in use.
Find a Certified Backflow Tester in Illinois
Find Illinois-licensed plumbers with CCCDI certification at getyourbackflowtested.com/backflow-testing-near-me/illinois-backflow-testing — covering Chicago, suburban Chicagoland, Springfield, Peoria, Rockford, and all major Illinois markets.
Illinois Regulatory Reference Links
| Resource / Agency | URL / Link Target |
|---|---|
IEPA — Cross Connection Control | |
Illinois Administrative Code Title 77, Part 890, Section 890.1130 | |
ERTC at SIUE — CCCDI Certification | |
ISAWWA — StopBackflow.info Resource | |
BSI Online — Illinois Compliance Portal | |
Chicago Department of Water Management |