Avondale City Code 24-6 and 24-7: which backflow assembly you need and where it goes

Section 24-4(a) starts the process: "An approved backflow prevention method shall be utilized or installed at every water service connection to a customer's water system when the director determines" that the public water could be contaminated by conditions inside the customer's system. Section 24-4(b) then says the department decides the method, sized to the hazard.

Section 24-6 ranks the approved methods from most to least restrictive:

"A reduced-pressure assembly is required at all direct connections to the public potable water supply for domestic use as close to the meter as feasible."

That is item (2). The full ladder in 24-6(b):

1. 1Air gap. Required when hazardous activities are conducted and served by the same water service connection or by multiple connections.
2. 2Reduced-pressure assembly (RPA). Required at all direct domestic connections, as close to the meter as feasible.
3. 3Reduced-pressure detector assembly (RPDA). Required on all fire systems that use chemical additives for fire suppression.
4. 4Double check valve assembly (DCVA). Required on all fire systems supplying water only to fire sprinkler systems.

If several activities share one premises, 24-6(a) applies the most restrictive method required for any of them to each water service connection. Section 24-7 covers installation: the customer installs the assembly at the customer's expense, in an accessible location the department approves, "as close to the water service connection as possible."

• Direct connection for domestic use. The code does not define it. The practical reading is the ordinary service line that feeds a building's sinks, toilets and water heater. That is a reading, not a definition.
• Hazardous activities. Not defined by a list. Section 24-5 sorts hazards into four factors (health, plumbing, pollution and system), and ties the health factor to "the judgment of the director."
• Department and director. Section 24-1 defines the department as the Avondale Public Works Department and the director as the person in charge of it or a designee.

Section 24-3 says the article applies to all new and existing customers, and that backflow assemblies installed before the article that do not comply "shall be replaced with approved backflow prevention assemblies." That puts old, non-conforming assemblies in scope, not just new installs.

It does not make every property need an assembly. The trigger in 24-4 is the director's determination about a hazard.

A new restaurant space. The domestic line gets an RPA near the meter. Section 24-7(f) says that after installation the customer must have an initial test on the assembly and have it inspected by the department "before the certificate of occupancy can be issued." The assembly is on the critical path to opening day.

A replacement. The old assembly was installed before the article took effect and does not meet it. Section 24-3(b) says non-complying assemblies "shall be replaced with approved backflow prevention assemblies."

The edge case. A buried-vault layout looks tidy, but 24-7(c) puts RPAs and pressure vacuum breakers above grade between 12 and 24 inches. Only the double check assembly gets the option of a below-ground vault, so a vault layout works for a double check assembly and not for an RPA.

1. 1Ask the Public Works Department which method it has determined for your connection (24-4(b)).
2. 2Ask for its list of approved assemblies by type and manufacturer. Section 24-6(d) says the department furnishes it to any customer required to install one.
3. 3Get the city backflow permit before work starts: 24-7(a) allows installation "only upon receipt of the necessary city backflow permit." Avondale's Development Services Department takes development applications online through the Accela Citizen Access portal and answers questions at (623) 333-4000, so start there to confirm the record type for a backflow permit.
4. 4Check the fee on the city's FY 2026 Rates & Fees Schedule, which lists a Backflow Permit Fee of $50.00 each (Municipal Code 24-04). The same schedule also lists "Water - Backflow Preventer" lines of $75.00 (up to 3 inches) and $120.00 (3 inches and greater) and a Landscape Backflow Preventer line of $125.00. It does not say which line fits your assembly, so ask which one applies.
5. 5Request the initial test and the department's inspection once the assembly is in, and do it early if a certificate of occupancy depends on it.

HQ Plumbing & Air installs, tests and replaces domestic backflow assemblies. Fire-line assemblies are outside what we do.

• Myth: only restaurants and factories need one. Section 24-6(b)(2) puts an RPA on every direct domestic connection, and 24-4 turns on the director's determination, not on a list of business types.
• Myth: any location near the meter works. The RPA and pressure vacuum breaker rule is above grade, 12 to 24 inches.
• Myth: the assembly is the end of it. Annual testing starts right after, and the Avondale annual testing page covers it.
• Myth: a bypass is a shortcut. Section 24-7(h) makes bypassing a backflow prevention method unlawful and a misdemeanor, with an exception in 24-13(b).

The text comes from Avondale City Code 24-3 to 24-8 on Municode and the city's FY 2026 Rates & Fees Schedule, read on 2026-10-04. This page explains them, and the official text governs.