Irrigation backflow testing in Upstate SC

If this page and the letter on your account disagree, follow the letter and the manual it cites. What is backflow testing is the general annual-test rule. This page is the lawn and in-ground irrigation case on the three Upstate utilities that publish a manual.

What the state rule splits

R.61-58.7(F) section (3) is only about residential lawn irrigation.

Section (3)(a) says each public water system that has low-hazard residential irrigation connected to it must have a written policy, approved by the system’s governing body. The policy names the minimum device. The minimum the regulation accepts for a low-hazard residential lawn sprinkler system is a residential dual check. If the system requires some other assembly instead, the policy has to be adopted with a chance for public comment. The written policy has to do three things:

• Name the device or assembly required on low-hazard residential lawn irrigation connections.
• If that minimum is a double check valve assembly or another testable assembly, set how often it is tested, and keep records that show the system is following that schedule.
• If the minimum is a residential dual check, set how often those devices are changed out, and keep records of the change-outs.

Section (3)(b) is the other case. A residential lawn irrigation system that includes chemical addition, or that is also connected to a water source which is not an approved public water system, is a high-hazard cross connection. It has to meet section (4): an air gap or an approved reduced pressure principle assembly. That assembly is the device covered on RPZ testing.

Section (7) is the test. When a double check valve assembly, a pressure vacuum breaker, or a reduced pressure principle assembly protects the public system, a certified tester tests it after installation and before the customer uses it. Except for the schedule in paragraph (3)(a)(ii) — the low-hazard residential policy’s own test frequency — each of those assemblies is tested at least once a year. The tester sends the written report to the water system. After any repair, the assembly is tested again immediately.

A residential dual check is the device in paragraph (3)(a)(iii). Greenville Water’s manual and Spartanburg Water’s manual both describe it as two spring-assisted check valves with no shutoff valves and no test cocks. There is no gauge test of that device. The policy’s job is the change-out schedule.

The residential dual-check sentence is about residential lawn irrigation. It does not name commercial irrigation. A commercial irrigation account follows the hazard the utility assigns. A testable assembly on that account follows section (7) unless the notice says otherwise.

SCDES still links a June 15, 2005 policy letter from the program page. The letter says the regulation was amended, effective April 29, 2005, so each water system would adopt a written policy for existing and future residential lawn irrigation. The letter told systems that chose a testable assembly to state the test frequency, and systems that chose a residential dual check to state the change-out frequency. The current text of section (3) is the regulation file linked above, not the letter by itself.

Greenville Water

The manual’s introduction says the policy was adopted September 6, 2022. The PDF file was created November 10, 2025. The introduction says most commercial, industrial, irrigation (as noted), and private fire-protection customers install, maintain, and test the assembly on the service. Section 5-3 is the note for residential irrigation.

Section 5-3 says a dual check on the meter setter is required for newly installed residential irrigation systems only. Section 5-3.2 says that dual check is part of the meter setter on newly installed meters, and Greenville Water replaces the internal parts once every thirty years.

Section 5-3.1 says existing residential irrigation that still uses a double check valve assembly is being phased out. Greenville Water is installing dual-check meter setters in place of those testable double checks. If the double check is not replaced within fifteen years of the effective date of the policy, a certified tester tests it then, and once every fifteen years after that. The introduction dates the policy’s adoption as September 6, 2022. The manual does not print a calendar day for that fifteen-year mark.

Section 5-1 still says a high hazard uses a reduced pressure principle assembly or an air gap, and a low hazard uses a double check valve assembly or a dual check. Section 5-3 does not add a separate sentence for a residential irrigation system that injects chemicals or ties in another water source. That case remains section (3)(b) of the state rule. If the notice names a testable assembly, use the notice.

Section 7 applies to testable assemblies. A new testable assembly is tested at installation, before the customer uses it, and the report has to reach Greenville Water within 10 days of the water service starting. Section 7-2 says existing assemblies are tested at least annually as determined by the current cross-connection policy, and the customer has the test made within 45 days of the scheduled due date. For a residential-irrigation double check that section 5-3.1 has not replaced, that policy states the fifteen-year test above. Notice timing and the non-compliance fee are on the Greenville Water page. Greenville Water’s backflow page says the utility does not install or test backflow preventers. The manual’s section 5-3.2 is the narrower line: Greenville Water replaces the internal parts of the new residential-irrigation dual check on the schedule above. Questions in the manual go to the Cross Connection Control Department at (864) 241-6100. Who installs a new assembly is on Backflow preventer installation.

Spartanburg Water

The manual revised June 4, 2026 (PDF created June 5, 2026) defines residential lawn irrigation (low hazard) as any irrigation system on a single-family dwelling that has no chemical injection system and no auxiliary water source.

Section 10.1’s low-hazard paragraph says customers who operate those systems install at least a dual check. The device is replaced with the meter change-out program, or if it malfunctions. The definitions section says replacement of residential dual checks coincides with the meter change-out schedule used by Field Technical Services.

Section 10.1’s high-hazard paragraph says a high-hazard residential lawn irrigation system has to meet the high-hazard cross-connection requirements, including a reduced pressure assembly, and that regulation requires an annual test of that device.

Section 10.2 says all existing approved backflow assemblies are tested annually, excluding low-hazard residential lawn irrigation systems. Customers with assemblies on that annual schedule get a Tier 1 letter 30 days before the test is due. The later tiers, the failed-test clock, and the administrative fee are on the Spartanburg Water page.

Section 6, and the Cross Connection and Backflow page, say a residential customer with a 3/4-inch to 1-inch service gets a residential dual check installed by Spartanburg Water. Commercial, industrial, and multi-dwelling customers get an approved testable assembly based on the hazard the cross-connection technicians identify. Questions on that page go to Matthew Jamison, Field Operations Manager, at (864) 598-7213 or ccc@spartanburgwater.org.

Anderson Electric City

The September 2008 Cross Connection Control Policy says Table 1 is a guide and that every service is evaluated on its own. On that table, landscape irrigation with injection of any type is listed as high hazard. Lawn irrigation without injection, commercial and residential, is listed as low hazard. The same low-hazard list includes interconnections with surface-water intakes, with a lake irrigation system given as an example. Section (3)(b) of the state rule treats a residential lawn system that is also connected to a water source other than an approved public system as high hazard. The policy says the table does not replace a case-by-case evaluation. Use the notice Electric City sends for the account.

The policy’s device rule: a high hazard requires an air gap, a reduced pressure principle assembly, or a pressure vacuum breaker, and a pressure vacuum breaker is not used where backpressure is expected. A low hazard may use those or a double check valve assembly. Atmospheric vacuum breakers, barometric loops, double checks with an intermediate atmospheric vent, and hose-bib vacuum breakers are not approved to protect the public system. The policy says they may be used for internal protection, and that an additional device is still required under the policy.

For an irrigation tap, the first contact named in the policy is the Water Administration Department. Protection on an in-ground system follows the hazard in Table 1.

• Above-ground sprinklers only, on the domestic meter: the customer does not install a device beyond what Electric City supplies at or near the meter.
• An irrigation meter teed off the domestic service: a backflow prevention device is required regardless of irrigation method. The pipe size in that sentence does not come through as a readable number in the PDF text. Take the size from the policy itself.
• In-ground irrigation on the domestic service: the device follows Table 1.
• An unprotected in-ground system, whether or not it is running, still needs a device installed and tested under the policy. That includes systems fed only from the domestic service with no separate irrigation connection.

A typical single-family domestic service without in-ground irrigation is the other case. Electric City supplies the protection at or near the meter and says it will install and maintain those devices at no additional expense to the customer. The device named there is a residential dual check, ASSE 1024. That sentence is for the house service. It is not the in-ground irrigation test below.

Residential in-ground irrigation devices are tested at installation and every 12 months after that. Commercial in-ground irrigation devices are on the same 12-month schedule. The tester has a current SC DHEC card and is in good standing with Electric City. Current cards are SCDES cards, as the program page describes. Reminder letters go out about 30 days before the test is due. Results have to meet Table 2. The tester sends the form to the Cross Connection Control Coordinator within 10 days of the test, and no later than 45 days after the customer received the form. The policy says the 45-day figure is “per ordinance.” The 90-day figure used for other customers is on the Anderson, Pickens, and Oconee page. A defective device is repaired or replaced as soon as possible, and no later than 20 business days after the failed test. Questions in the policy go to the coordinator at (864) 231-5230.

On an in-ground system, the tester also checks the installation:

• If a reduced pressure assembly is in a pit, the tester inspects the pit drain at the annual test, writes that inspection on the form, and a drain that is slow or clogged is cleaned or repaired immediately. A sump pump is not a substitute for a gravity drain. The relief opening points toward the ground. The policy allows no vertical or angled installation.
• If the device is a pressure vacuum breaker, the tester checks that no permanent debris, such as a shrub, sits within 1 foot in any direction, and that the device is at least 12 inches above all downstream piping. The tester documents debris on the form and does not remove it. Electric City follows up, and debris still there 14 days after the test puts the customer at risk of disconnection until the condition is fixed. The installation section also says a pressure vacuum breaker is above ground, is never installed inside a building, and has a landscaping setback of 3 feet. Section (9) of the state rule requires the same 12-inch height and says the assembly is not subject to backpressure.

Table 2 is Anderson’s minimum for a passing test. It is not printed in the Greenville Water or Spartanburg Water sections read for this page, and it is not a statewide number from R.61-58.7(F). For a pressure vacuum breaker, Table 2 lists the check at 1.0 psi minimum and 4.0 psi maximum, and the air inlet valve at 1.0 psi maximum and 4.0 psi maximum. For a double check valve assembly tested with a differential gauge, both checks close tight and hold a minimum of 1.0 psi. The reduced-pressure bands are on RPZ testing.

The same table still describes a vertical-tube direction-of-flow test for a double check. A letter dated June 1, 2018, linked from the SCDES program page, says the Department will no longer allow the vertical-tube procedure for a double check valve assembly as of December 31, 2018. From January 1, 2019, the letter says the two remaining options both use the tester’s differential gauge: the differential-pressure test and the direction-of-flow test. Anderson’s 2008 policy has not been replaced in the file linked above. The later letter is the one the program page still publishes.

The policy says the customer pays applicable reconnection fees if service is disconnected. It does not print the fee amount in the sections read for this page.

If your water system is not one of these three

This page does not state an irrigation rule for Greer, Seneca, Easley, Blue Ridge Rural Water, or any utility that has not published the document cited here. The state split in section (3) still applies. The device, the test date, and the place the report goes are on that utility’s notice.

Who can test a testable irrigation assembly

In R.61-58, a certified tester holds an up-to-date card from the Department. The classification that tests for the general public is the General Tester. A Limited Tester tests only assemblies the employer owns. General vs Limited has the course and the gauge rule.

County pages copy General Testers from the SCDES report printed July 9, 2026. Start with Greenville County, Spartanburg County, or Anderson County. Confirm the current card before you hire. A row on this site is not an appointment, and it is not a list of irrigation installers.

Assemblies used in South Carolina have to be on SCDES’s approved-assembly list. SCDES publishes a sample test form. The form says many jurisdictions require their own form.

This site does not publish an irrigation-only price. The cost guide keeps a third-party range for the test, labeled as that site’s range, and keeps utility fees separate. Official links are on Resources.

Sources checked October 10, 2026: R.61-58.7 in the regulation PDF on des.sc.gov, the SCDES program page, the June 15, 2005 lawn-irrigation policy letter, the June 1, 2018 vertical-tube letter linked from that page, Greenville Water’s backflow page and November 10, 2025 manual, Spartanburg Water’s cross-connection page and June 4, 2026 manual, and Anderson Electric City’s September 2008 policy.