Backflow Prevention

Cross-Connection Control & Backflow Prevention

Cross-Connection Control is the prevention of actual or potential connections between the public water supply and a source of contamination or pollution. Backflow prevention devices prevent the unwanted reversal of flow from an end user’s water system back into the public water supply.

The Technical Services section provides expert consultation for installation of backflow prevention devices of industrial, commercial, and residential applications for domestic, fire protection, and irrigation systems. Water connections are assessed for the degree of hazard they present and backflow preventer requirements are determined by city staff.

Property owners are responsible for the installation, operation, testing, and maintenance of required backflow prevention devices.

The Cross-Connection Control Program serves as a technical reference for policy requirements and industry standards. For more information, please call 336-650-7651.

Test Report Submissions

Test reports are only accepted from testing companies registered to test within WSFC Utilities.  All failed assemblies must be repaired or replaced at the owner’s expense. An initial test report with passing results is required for all new or replaced assemblies. To register as a testing company, submit documentation, including Tester Certification and Test Kit Calibrations, to BSI-Online at or faxed to 888-414-4990. All test reports must be sent to BSI-Online. If you have any questions, please contact BSI-Online customer support at 800-414-4990.

*If setting up a new installation, theTest and Maintenance Report should be sent directly to the Cross Connection Control Supervisor, Tom McEwen.

Annual Backflow Assembly Testing Notifications

The State of North Carolina requires backflow prevention assemblies be installed on all cross-connections to help keep our water supply safe. These assemblies must be tested and certified every year to ensure that they are working properly. 

Winston-Salem/Forsyth County Utilities has partnered with BSI-Online to assist in administering the backflow program for our system. BSI-Online sends out notification letters to customers that are listed in our records as having backflow prevention assemblies. The letters are sent 30 days prior to assembly testing due date. 

Important information included in the letter:

  • The customer’s name on the water billing account.
  • The physical address of the property where the backflow assembly is listed. 
  • Information concerning the assemblies requiring testing. 
  • The “Test Due Date”.
  • Customer Confirmation Number, located in the upper right corner. This is the number used by the backflow testing company to upload test reports for the property.

Please note in the upper left corner, customers may notice an Illinois return address. This is accurate, as BSI-Online is located in the state of Illinois.

 View Sample Notice (PDF)

BSI-Online provides customer service concerning backflow prevention for Winston Salem/Forsyth County Utilities customers. Customers can call and speak with a representative, Monday- Friday, 8:00 - 5:00pm at 888-966-6050, or send an email to

Permits for Fire Hydrant Connection or Tanker Water Use

Print and submit our Fire Hydrant Connection/Tanker Water Use Permit Application (PDF) in-person with payment by cash, check, Visa, Mastercard or Discover at Utilities Customer Service located in the Bryce A. Stuart Municipal Building Monday - Friday from 8 a.m. - 5 p.m. Applications can also be mailed to the address below:

Bryce A. Stuart Municipal Building
ATTN: Utilities Customer Service
100 East First Street, Suite 121
Winston-Salem, NC 27101

The following is a summary of application information from Winston-Salem, NC Water System Policy, Article I, Sec. 17 (b).
View the official policy.

  1. Fire Hydrant Meter
  2. Tanker Water Use
  1. Applicants requesting water service from a fire hydrant must apply to Winston-Salem/Forsyth County Utilities (WSFC Utilities) at least five business days prior to the first date of requested service.
  2. Complete the Fire Hydrant Connection/Tanker Water Use Permit Application with all required information and submit with a $500 non-refundable application fee. Incomplete applications will not be approved.
  3. A $1,500 deposit is required for each reduced pressure backflow hydrant meter assembly and will be applied to the cost of water consumption, potential damages to the hydrant or backflow hydrant meter assembly or any additional costs incurred by WSFC Utilities. See the hydrant meter damage repair costs document for more details.
  4. Fire hydrant connection permits are valid for six months. When six months expires, the applicant will be required to reapply and pay the fee for a new permit.
  5. Applicants must clearly demonstrate an engineering requirement for a higher volume of water than can be delivered through a temporary two-inch or smaller water service connection.
  6. WSFC Utilities reserves the right to deny any application for any fire hydrant connection, and at the applicant’s expense may require installation of a temporary two-inch or smaller water service connection with an approved reduced pressure backflow preventer assembly.
  7. WSFC Utilities owns and maintains a limited number of reduced pressure hydrant meter assemblies and may deny an application due to lack of availability.
  8. Only one specific fire hydrant will be authorized for use by an approved fire hydrant connection permit. A separate permit application is required to use any other fire hydrant, even if located at the same work site.

See next tab for Tanker Water Use information.