Backflow preventer installation in the Upstate

R.61-58.7(F) says no person may install or keep a cross connection between a public water system and any other non-public water system, a sewer, or a line from a container of liquids or other substances, unless an approved backflow prevention device or assembly sits between the public system and the source of contamination. The regulation names the device and the test. It does not name a trade that is allowed to set the assembly. What is backflow testing is the test. This page is the installation step on the three Upstate utilities that publish a manual.

If this page and the letter on your account disagree, follow the letter and the manual it cites.

Who installs it

Greenville Water

Greenville Water’s backflow page says customers whose water presents a backflow hazard must install a device or assembly and have it tested annually under SCDES and Greenville Water standards. The same page says Greenville Water does not install or test backflow preventers.

The Cross Connection Control Manual (PDF created November 10, 2025; the policy inside was adopted September 6, 2022) puts the work on the customer:

• Section 2-4 says the customer shall install, test, and maintain the assemblies Greenville Water, the health official, or the authority having jurisdiction requires. The customer is responsible for all costs of purchase, installation, testing, and maintenance, including when the customer does not own the piping past the service connection. The customer obtains the permits and inspections the plumbing official requires. The customer should contact the Cross Connection Control Department before buying or installing an assembly. The number printed in the manual’s introduction is (864) 241-6100.
• Section 2-2 names the plumbing official as the City of Greenville plumbing inspector or the Greenville County building inspectors. That official enforces the International Plumbing Code as adopted for the area, from the service connection out to the ends of the customer’s system.
• Section 5-4.9 says the customer’s plumber or contractor installs thrust restraints. Greenville Water may require more after the inspection.
• Section 7-1 says the installer contacts a certified tester. The installer and the tester are two roles in that sentence.

One residential case is different. Section 5-3 says a dual check on the meter setter is required for newly installed residential irrigation systems only. Greenville Water replaces the internal parts of that assembly once every thirty years. Existing residential irrigation that still has a double check valve assembly is being moved to a dual-check meter setter. If that 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.

Spartanburg Water

Spartanburg Water’s Cross Connection and Backflow page says a residential customer with a 3/4-inch to 1-inch service will have a residential dual check valve installed by Spartanburg Water. Commercial, industrial, and multi-dwelling customers get an approved testable assembly based on the degree of 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.

The manual revised June 4, 2026 (PDF created June 5, 2026) repeats that residential dual-check line in section 6. For an assembly Spartanburg Water requires in writing, section 5 says the customer installs it at the customer’s expense. Failure to install, have it tested as required, and maintain it can be grounds for discontinuing service. The same section says the customer should contact Spartanburg Water before buying or installing an assembly.

Section 5 also separates the installer from the tester. The installer’s duty is to make sure each assembly is working properly, and the assembly must be tested by an SCDES-approved tester when it is installed and before the system is placed in service. The tester is described there as an independent contractor certified by SCDES to test assemblies for Spartanburg Water customers.

Anderson Electric City

The September 2008 Cross Connection Control Policy says the customer has the sole responsibility to keep backflow out of the Electric City system by installing an approved device, and shall install, test, and maintain those systems. If a cross connection or a potential one exists, the water user installs, has tested, and maintains an approved device at the water user’s expense. The policy names the plumbing official as the City of Anderson Building and Codes or Anderson County Building Codes, enforcing the International Plumbing Code as adopted for the area. Questions in the policy go to the Cross Connection Control Coordinator at (864) 231-5230. The policy still says “SC DHEC.” Current tester cards are SCDES cards, as the program page describes.

A typical single-family domestic service without in-ground irrigation is the exception printed in that policy. Electric City supplies the protection at or near the meter and will install and maintain those devices at no additional expense to the customer. Standard residential domestic services get a residential dual check (ASSE 1024) on a meter yoke or as a stand-alone device, on new or renewed services. The policy says that exception is allowed by SC DHEC.

New customers for a device contact Electric City’s Water Operations Department first. The proper device is installed before water service is established. The installer, contractor, or owner meets an Electric City representative to inspect it. If the installation is correct, permission to establish service is granted and a test form is provided. If it is not, water stays off until it is reinstalled and inspected again. The tester has three days to test the device once Electric City personnel establish water service. A completed form goes to the coordinator within 10 days of the test, and no later than 90 days after the customer received the form, or 45 days for in-ground irrigation. The device-installation section also says the curb stop stays locked off until the installer meets a representative on site, and the installer then has 10 days to return the completed test form. Deadlines already summarized for existing Anderson customers are on the Anderson, Pickens, and Oconee page.

This page does not state an installation rule for Greer, Seneca, Easley, or any utility that has not published the document cited here. Use the notice from that utility.

The test is a separate step

Section (7) of R.61-58.7(F) applies when a double check valve assembly, a pressure vacuum breaker, or a reduced pressure principle assembly protects the public system:

• A certified tester tests the assembly after installation and before the customer uses it.
• Except for the low-hazard residential irrigation case in section (3), a certified tester tests each assembly at least once a year.
• The public water system receives a written report. The certified tester who made the test submits it.
• After a repair of any kind, the assembly is tested again immediately.

Greenville Water’s section 7-1 matches that first test: a new testable assembly is tested upon installation and before the customer uses it, the installer contacts a certified tester, and Greenville Water must receive the report within 10 days of the water service starting. The site inspection is a different visit. Sections 3-1.5 and 3-1.6 say the customer notifies the Cross Connection Control Department at least two days before that inspection at (864) 241-6100. If the installation is satisfactory, the meter or service is unlocked. Inspection vs testing follows that split. Notice timing and the non-compliance fee are on the Greenville Water page.

For a new Spartanburg Water connection, section 8.1 says Spartanburg Water evaluates the service, tells the customer the assembly and an installation timeline, and inspects the finished installation. The meter or service is unlocked if the installation is satisfactory. For an existing connection, section 8.2 says the customer notifies Spartanburg Water at least 7 calendar days before the required inspection. The annual notice tiers are on the Spartanburg Water page.

The credential for the test is an SCDES tester card. The classification that tests for the general public is the General Tester. General vs Limited explains the four cards, and notes that installing or replacing an assembly for hire can raise a separate licensing question with the South Carolina Department of Labor, Licensing and Regulation. 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 the tester list. It is not a list of installers, and it is not an appointment.

This site does not publish an installation price. The cost guide is a third-party range for the test, labeled as that site’s range.

What may be installed

The SCDES program page says assemblies used in South Carolina must be on SCDES’s list of approved backflow prevention assemblies. The January 1, 2026 list tells the reader to weigh these points before choosing an assembly:

• Local plumbing laws, codes, and regulations apply.
• The manufacturer’s installation instructions are followed.
• A reduced pressure principle assembly is installed so the relief port is never submerged or in a toxic environment. That prohibits a pit that cannot drain by gravity to the ground surface. A vertical orientation is not acceptable unless the University of Southern California’s Foundation for Cross Connection Control and Hydraulic Research has approved it.
• Assemblies are tested immediately after installation and at least once a year after that, except as section 3 of the regulation outlines.
• Bypass piping is not permitted unless the bypass has an approved assembly similar to the main-line assembly.
• SCDES may add an assembly to the list or remove one.

The regulation’s hazard classes, which your utility applies to the account:

• A low hazard, section (2), has a minimum of an approved double check valve assembly or a pressure vacuum breaker, except for the residential dual-check policy in section (3).
• A high hazard, section (4), is protected by an air gap or an approved reduced pressure principle assembly. Those assemblies are not installed where flooding is possible, including a pit or vault without a gravity drain to the surface that can pass more water than the relief valve discharges.
• Fire-line sprinklers use an approved double check valve assembly, except high-hazard systems, which follow section (4). The rule’s examples include antifreeze, foam, and systems charged from or tied to a pond, lake, stream, or any source other than the approved public supply.
• Where a pressure vacuum breaker is used, section (9) says it is installed at least 12 inches above the highest downstream piping and is not subject to backpressure.

This page does not choose the assembly for an address. The utility’s notice does.

Where the three manuals place it

Greenville Water section 5-2 says installation is usually in a box near the meter or inside a building in a mechanical area, before the first connection off the service line. Greenville Water reviews each site. Section 5-4.8 says every assembly goes in an enclosure or building on the customer’s property, protected from freezing, traffic, and vandalism, and kept accessible for testing and maintenance. Section 5-4.4 does not allow a bypass unless an equal assembly is in the bypass. Section 5-5.4 discourages underground installation of a reduced pressure assembly and allows it only in unusual cases where a gravity drain to the surface can be installed. The relief-valve air gap for that assembly is on RPZ testing.

Spartanburg Water section 9.2 says installation is usually in a structure directly behind the meter box, near the property line, or immediately inside the building in a mechanical area, before the first connection off the service line. Spartanburg Water reviews each site. Section 9.3 requires an enclosure or building on the customer’s property for the same freeze, traffic, and vandalism reasons, requires the manufacturer’s instructions, and says no black iron or black steel piping is installed on the supply side of any assembly. A bypass needs an equal assembly in the bypass. Section 9.4 discourages underground reduced-pressure installations and allows them only in exceptional cases, one site at a time, where a gravity drain can be installed.

Anderson’s device-installation section says assemblies go at the property or right-of-way boundary, on the customer’s side of the meter. Electric City may grant an exception in writing before the work, based on space, piping, safety, or protection of the assembly. An exception is not granted if the structure is more than 60 feet from the right-of-way boundary. The device is not closer to the meter than 12 inches and not farther than 6 feet, measured from the outlet of the meter yoke or flange to the inlet shutoff or strainer. Above-ground installations are protected against freezing. A double check or reduced pressure assembly installed above ground or inside a building sits no lower than 12 inches and no higher than 36 inches above grade or the floor, and it stays reachable for testing without a ladder. Reduced pressure assemblies are above ground unless Electric City specifies otherwise. The relief opening points toward the ground. The policy allows no vertical or angled installation. Pressure vacuum breakers are above ground, at least 12 inches above the highest downstream piping, and are never installed inside a building. The same section sets pipe materials, shutoff valves, and pit drains. Those details are in the PDF.

Closed plumbing after the preventer is in

Spartanburg Water’s section 13 says that once a backflow preventer or a dual check is on the service, heated water can no longer expand back into the utility main. The manual calls that a closed system and names thermal expansion. It suggests discussing three options with a licensed plumber: a bladder-type expansion tank, a special ball cock and relief valve in the water closet, or a remote thermal expansion relief valve. The same paragraph says those three methods can be do-it-yourself projects. The number printed there for thermal-expansion questions is 864-585-8296. Program questions on the public page still go to the contact named above.

Greenville Water’s section 2-4 says the customer maintains fixtures that accommodate changes in water pressure, including thermal expansion tanks, relief valves, and pressure reducing valves. The manual says Greenville Water’s supply pressure varies and that the supply can be shut off for repairs, maintenance, and construction.

Sources checked October 9, 2026: R.61-58.7 on des.sc.gov, the SCDES program page, the January 1, 2026 approved-assembly list, 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.