Backflow Laws: Indiana
Indiana Backflow Prevention Laws, Regulations, and Compliance Requirements
Indiana's backflow prevention requirements are governed by Indiana Administrative Code 327 IAC 8-10, administered by the Indiana Department of Environmental Management (IDEM). Indiana requires annual testing by IDEM-registered Cross-Connection Control Device Inspectors, test results reported on State Form 55788 within 30 days, and submission to the water utility (not to IDEM directly). Carmel has a notable local ordinance with semi-annual RPZ testing. This guide covers Indiana's full regulatory framework, IDEM's registered tester program, and requirements for Citizens Energy Group (Indianapolis), Carmel, and other major Indiana utilities.
Indiana State Regulatory Framework
Indiana’s cross-connection control and backflow prevention program is established in Indiana Administrative Code 327 IAC 8-10, administered by IDEM (Indiana Department of Environmental Management). IDEM holds EPA primacy under the federal Safe Drinking Water Act and is responsible for administering state regulations for cross-connection control and water quality standards. The Indiana State Department of Health (ISDH) addresses water quality standards at 170 IAC 6-1-20, and the Indiana Department of Homeland Security oversees the Indiana Plumbing Code at 675 IAC 16-1.3-64 through 85.
327 IAC 8-10 requires that customers of public water systems install backflow prevention devices (by licensed installers) to protect the public water system from potential contamination. Devices must be tested at a minimum of once a year by IDEM-registered inspectors. Test results must be reported on the Backflow Device Test Form — State Form 55788 — and submitted to the water utility within 30 days of the test being completed. Results should not be sent to IDEM directly unless IDEM specifically requests them.
IDEM’s Cross Connection Control and Backflow Prevention Manual (most recently revised July 2016) provides detailed guidance for public water systems, backflow testers, homeowners, and industrial facilities. The 2016 edition incorporated revised rules effective December 13, 2012, a sample ordinance, the State Backflow Device Test Form, and clarifications on exemptions within the IDEM rule.
Approved Assemblies in Indiana
Approved backflow prevention assemblies in Indiana must be listed as approved by the USC Foundation for Cross-Connection Control and Hydraulic Research (USC-FCCCHR) at the time of installation. The City of Carmel specifies this explicitly in its local ordinance.
IDEM's Tester Registration Program
IDEM maintains a list of licensed Backflow Inspectors who are Registered Cross-Connection Control Device Inspectors for Indiana. Testers are certified after attending a 35-hour training class and passing a written examination and practical tests on backflow prevention devices. The IDEM tester registration does not expire in the traditional sense — however, testers wishing to remain on IDEM’s ‘Active’ list must complete the Active list questionnaire when sent. License or registration numbers can be verified on the Indiana Professional Licensing Agency website at pla.IN.gov.
Fire Line Exemption Under 327 IAC 8-10-4
Indiana has a specific exemption for certain dedicated fire lines from the standard backflow protection assembly requirements. Under 327 IAC 8-10-4(a)(2) and 327 IAC 8-10-6, the exemption applies to fire suppression systems meeting all conditions in the rule: the system must be looped with no dead ends, must have no non-potable connections, must not have a fire department hose (Siamese) connection, must have 20 sprinkler heads or fewer, and must be constructed of potable water supply quality pipe. When any of these conditions are not met, double detector check valve or double check valve assembly protection is required at the fire system’s connection point.
Indiana's State Form 55788 Is the Required Test Report Document
Indiana requires that backflow device test results be reported on State Form 55788 — the official IDEM Backflow Device Test Form. Results cannot simply be reported on a contractor’s generic test form. The completed State Form 55788 must be submitted to the water utility within 30 days of testing. IDEM does not receive test reports directly unless specifically requesting them for compliance review. Many Indiana utilities have adopted third-party platforms that accept electronic submission of the equivalent information.
Major Water Purveyors in Indiana
Citizens Energy Group (Indianapolis)
Citizens Energy Group is the primary water utility for Indianapolis and Marion County, serving approximately 300,000 customers. Citizens has partnered with Aqua Backflow — a technology-based backflow management firm — to implement its cross-connection control program. Citizens will only accept backflow device test results submitted through TrackMyBackflow.com. Testers must currently be IDEM-certified AND registered with Aqua Backflow at TrackMyBackflow.com before submitting results. IDEM certification alone is not sufficient — utility registration with the Aqua Backflow platform is also required for testing in Citizens’ service area.
Citizens requires annual testing by IDEM-certified testers. All costs — installation, maintenance, testing, repair — are the customer’s responsibility. Property owners receive notification letters from Aqua Backflow when testing is due.
City of Carmel Utilities
Carmel has enacted local ordinance A-69 governing cross-connection control. Carmel’s program includes a notable distinction on testing frequency: Reduced Pressure Principle (RP) assemblies must be tested at intervals not exceeding six months (semi-annually) unless installed on an irrigation system, in which case annual testing applies. This semi-annual RPZ testing frequency for non-irrigation applications is more demanding than IDEM’s minimum annual standard and makes Carmel one of Indiana’s more stringent local programs.
Air Gaps in Carmel must be inspected annually. USC-FCCCHR approved assemblies are required. New backflow assembly installations and replacements must be reported to Carmel Utilities for a Backflow Replacement Inspection before the new assembly can be put into service, ensuring IDEM specifications and utility requirements are verified.
Indiana American Water
Indiana American Water serves multiple Indiana communities and is the largest investor-owned water utility in the state. Indiana American Water aligns with 327 IAC 8-10 requirements for annual testing. Test results are submitted to Indiana American Water through the utility’s designated procedure.
Fort Wayne City Utilities
Fort Wayne City Utilities serves Indiana’s second-largest city. Fort Wayne’s cross-connection control program requires annual testing for all commercial, industrial, and high-hazard residential connections. Results are submitted to Fort Wayne City Utilities within the 30-day window required by 327 IAC 8-10.
Other Notable Indiana Utilities
South Bend, Evansville, Muncie, Terre Haute, Bloomington, and Hammond each operate cross-connection control programs aligned with IDEM requirements. The Indiana Rural Water Association provides technical assistance to smaller rural Indiana water systems implementing their first cross-connection control programs. Rural systems must maintain the three most recent test reports for any registered backflow device and make them available for IDEM review.
Carmel's Semi-Annual RPZ Testing Requirement
Property managers with commercial or industrial properties in Carmel, Indiana should be aware that RPZ assemblies require testing every six months (semi-annually) for non-irrigation applications under Carmel’s local ordinance — not annually as in the rest of Indiana. Scheduling a single annual test is not sufficient for RPZ assemblies in Carmel outside of irrigation applications. Calendar both testing dates at the start of each year to avoid compliance gaps.
Property Owner Compliance Summary for Indiana
Installation: By licensed installer using USC-FCCCHR approved assemblies.
Annual testing: By IDEM-certified Backflow Assembly Tester. Carmel: RPZ assemblies tested every 6 months (non-irrigation); annually for irrigation.
State Form 55788: Test results reported on this form within 30 days of testing, submitted to the water utility.
Citizens Energy: Results must go through Aqua Backflow at TrackMyBackflow.com. Testers must register with Aqua Backflow in addition to IDEM certification.
Fire systems: Confirm whether your fire suppression system qualifies for the IDEM exemption or requires DCVA/DDCVA protection.
Find a Certified Backflow Tester in Indiana
Find IDEM-registered backflow device inspectors at getyourbackflowtested.com/backflow-testing-near-me/indiana-backflow-testing — covering Indianapolis, Carmel, Fort Wayne, South Bend, and all major Indiana markets.
Indiana Regulatory Reference Links
| Resource / Agency | URL / Link Target |
|---|---|
IDEM — Cross-Connection Control and Backflow Prevention Manual | |
IDEM — Backflow Prevention Manual PDF | |
327 IAC 8-10 — Indiana Cross-Connection Control Rule | |
IDEM — Registered Cross-Connection Control Device Inspectors List | |
Citizens Energy Group — Backflow Prevention | |
Aqua Backflow (TrackMyBackflow.com) | |
Carmel Utilities — Backflow |