§ 4-170. Backflow prevention methods and devices.

(a)

Any irrigation system that is connected to the potable water supply must be connected in accordance with the plumbing chapter, Texas Commission on Environmental Quality rules, this chapter, and other relevant law. All backflow prevention assemblies shall be of a type and model approved by the regulatory authority. The backflow prevention device must be installed in accordance with the laboratory approval standards or if the approval does not include specific installation information, the manufacturer's current published recommendations.

(b)

If conditions that present a health hazard exist, one (1) of the following methods must be used to prevent backflow:

(1)

An air gap may be used if:

a.

There is an unobstructed physical separation; and

b.

The distance from the lowest point of the water supply outlet to the flood rim of the fixture or assembly into which the outlet discharges is at least one-inch or twice the diameter of the water supply outlet, whichever is greater.

(2)

Reduced pressure principle backflow prevention assemblies may be used if:

a.

The device is installed at a minimum of twelve (12) inches above ground in a location that will ensure that the assembly will not be submerged; and

b.

Drainage is provided for any water that may be discharged through the assembly relief valve.

(3)

Pressure vacuum breakers may be used if:

a.

No back-pressure condition will occur; and

b.

The device is installed at a minimum of twelve (12) inches above any downstream piping and the highest downstream opening. Pop-up sprinklers are measured from the retracted position from the top of the sprinkler.

(c)

Backflow prevention devices used in applications designated as health hazards must be tested upon installation and annually thereafter.

(d)

If an irrigation system is connected to a potable water supply and requires major maintenance, alteration, repair, or service, the system must be connected to the potable water supply through an approved, properly installed backflow prevention method before any major maintenance, alteration, repair, or service is performed.

(e)

If an irrigation system is connected to a potable water supply through a pressure vacuum breaker, or reduced pressure principle backflow assembly and includes an automatic master valve on the system, the automatic master valve must be installed on the discharge side of the backflow prevention assembly.

(f)

The irrigator shall ensure the backflow prevention device is tested by a licensed backflow prevention assembly tester prior to being placed in service and the test results shall be provided to the regulatory authority and to the irrigation system's owner or owner's representative within ten (10) business days of testing of the backflow prevention device.

(Ord. No. 2010-48, § 1(Exh. A), 11-2-10)