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Cross-Connection Control Survey

Per the Colorado Primary Drinking Water Regulations (Regulation 11), Denver Water is required to survey water service lines for potentially hazardous cross-connections, where water could flow from a property into the public water system and compromise the water quality for other customers.

Denver Water technicians are surveying the following:

  • Commercial property water service lines
  • Dedicated irrigation lines
  • Fire lines
  • Multi-family residential water service lines
  • Single-family residential water service lines with an auxiliary water supply, such as a well or pond
  • Recycled water service lines, if the plumbing system includes chemical injection or pumps

How long does it usually take to complete an inspection?

A typical inspection takes less than one hour to complete, depending on the size of the facility.

If I pass the inspection, do I need to do anything else?

If you pass the inspection we will provide information about Denver Water’s annual testing requirements so you can complete this year’s process and plan ahead for next year.

It is the customer's responsibility to hire a certified backflow prevention assembly tester to annually test assemblies and submit an annual Denver Water Test Report Form to

What happens if I do not pass the inspection?

If an unprotected cross-connection is discovered on the property, Denver Water will require you to install an approved backflow prevention assembly within 60 days of the survey. We realize that, in some cases, a longer period of time may be required for larger installations. The Cross-Connection Control office will need to be contacted for approval of any extended periods of time.

It is the customer's responsibility to hire a licensed installer to install a backflow prevention assembly. Upon installation, testing is required to be completed by a certified ABPA (American Backflow Prevention Association) or ASSE (American Society of Sanitary Engineering) tester within 48 hours of installation and send the test report(s) to Denver Water. The backflow prevention assembly is required thereafter to be tested annually by a certified backflow prevention assembly tester.

It is at the sole discretion of Denver Water's Cross-Connection Control office to suspend water service if the premises poses a health risk to the public water supply, when a backflow prevention assembly has not been installed or tested.

If you did not pass inspection and have specific questions please contact Cross-Connection Control at 303-628-5969.

Do you have any tips for passing an inspection?

See our helpful hints for passing a backflow assembly inspection.

Where should I send annual test reports?

Test reports may be emailed (preferred) or mailed:


Mailing Address:
Attn: Cross-Connection Control
1600 W 12TH Ave
Denver, CO 80204