Short definition
A cross-connection control program (CCCP) is the regulated system a public water utility uses to prevent contamination from flowing backward into the drinking-water supply. In Washington, every Group A water system runs a CCCP under WAC 246-290-490 — that’s why your irrigation backflow assembly gets tested every year by a certified tester.
What it is
A “cross-connection” is any point where the potable supply could mix with non-potable water — irrigation systems, fire protection, boilers, hose-end submersion in a bucket, chemical-injection lines, industrial processes. Three mechanisms can cause water to flow the wrong way:
- Back-siphonage — negative supply pressure (a main break, a fire hydrant flowing) sucks water backward through a connected fixture.
- Back-pressure — downstream pressure (a boiler, a pressurized irrigation system) exceeds supply pressure and pushes water back toward the main.
- Backflow — general reversal of normal flow.
A cross-connection control program identifies every connection where these can happen, requires installation of an approved backflow-prevention assembly sized to the hazard, and runs an inspection and testing schedule to make sure those assemblies actually work.
The program has three pillars: a written CCCP for each utility, at least one certified Cross-Connection Control Specialist (CCS) on staff or contract, and annual testing of every approved backflow assembly by a certified Backflow Assembly Tester (BAT).
Why it matters to a homeowner
Most homeowners interact with the CCCP through one specific channel: the annual backflow-test reminder card from their water utility. If you have an irrigation system with a PVB or RPZ, or a fire-sprinkler system, or a chemical-injection irrigation system, the utility expects you to hire a certified BAT to test the assembly each year and file the report. Ignore the reminder long enough, and the utility will shut off water service.
The reason this rule exists: a failed cross-connection can put pesticide-laden irrigation water, boiler glycol, sewage, or industrial chemicals into the drinking-water supply. Documented historical events (the Boston cross-connection cases, agricultural chemical contamination cases) caused real injury and death. The CCCP is a system that takes individual-property risk and aggregates it into utility-wide protection.
When you’ll encounter this term
- Annual reminder card from your water utility — hire a certified BAT to test, file the report
- Buying a home with irrigation: confirm a backflow assembly is present, tested, and on file with the utility
- Adding a fire sprinkler system in a remodel: triggers a DCVA or RPZ install plus permanent annual test obligation
- Adding chemical injection (fertilizer, herbicide) to landscape irrigation: RPZ required; some cities require additional permits
- Detached ADU on the same lot: may trigger a second backflow assembly depending on the AHJ
Common variants and disambiguation
- CCCP (utility program) vs. a backflow assembly (the device) — homeowners encounter the latter; the program is the regulatory framework that requires it.
- Group A vs. Group B vs. private well. Different rule chapters (WAC 246-290 vs. 246-291 vs. unregulated). Private wells aren’t part of the CCCP.
- Premises isolation (assembly at the meter, protecting the utility from the property) vs. internal protection (assembly at a fixture, protecting other fixtures in the building). CCCP enforces premises isolation; plumbing code enforces internal protection. Both may apply.
Approved assembly types
WAC 246-290-490 recognizes a graded list of assemblies, matched to the hazard level:
- Air gap (AG) — physical air break; highest level of protection.
- Reduced-pressure backflow assembly (RPBA / RPZ) — for high-hazard service connections.
- Double-check valve assembly (DCVA / DCDA) — for moderate-hazard.
- Pressure vacuum breaker (PVB) — common on residential irrigation.
- Atmospheric vacuum breaker (AVB) — simpler, for limited applications.
- Hose-bib vacuum breaker (HBVB) — the smallest assembly, screws onto a hose bib.
Common failure modes
- Homeowner unaware of test requirement. Builder-installed irrigation backflow assembly never tested; utility sends a tag warning, then service shutoff.
- PVB freeze damage in spring. Winter blow-out skipped; PVB body splits; fails the spring test.
- Lapsed BAT certification on the testing contractor. Homeowner pays for a “test” that the utility doesn’t accept.
- Homeowner removes an assembly to “fix water pressure.” Illegal removal, eventually flagged.
- Wrong assembly class for hazard. DCVA on a high-hazard line where RPZ is required.
Cost data
- Annual residential RPZ / DCVA test: $50–$150 typical statewide; some Seattle-area testers start at $73–$95.
- BAT certification (becoming a tester): $300–$500 course + exam fees through Washington Certification Services at Green River College.
- Failed assembly repair / replacement: $150–$800 typical residential.
- PVB freeze damage repair: $150–$400 for parts kit; $400–$800 for full assembly replacement.
Washington note
WAC 246-290-490 — the WA Department of Health Cross-Connection Control rule for Group A public water systems — is the load-bearing regulation. It requires:
- Each Group A water system to develop and implement a written CCCP
- At least one certified Cross-Connection Control Specialist (CCS) on staff or under contract
- Annual testing of all approved backflow assemblies by a certified Backflow Assembly Tester (BAT)
- Premises isolation (RPBA, RPDA, or air gap) for high-hazard service connections (hospitals, food processing, chemical plants — see Table 13 in the WAC)
WAC Chapter 246-292 covers Waterworks Operator Certification, including BAT (246-292-034) and CCS (246-292-033) duties. BAT certification in WA is administered by Washington Certification Services at Green River College. You can verify a tester’s certification at the WCS lookup before paying for a test.
Group B systems (smaller systems, under WAC 246-291) are also subject to cross-connection control but with less prescriptive rules. Private wells (single-family, not a public system) are not part of the CCCP — homeowner is the sole user, no public-health hazard from that supply alone.