All commercial customers are required to submit annual backflow prevention assembly tests and maintenance reports through the BSI Online tracking system. BSI can be reached by phone at 800-414-4990. Paper backflow test reports will no longer be accepted directly by the City of Toledo.

BSI Online

About Backflow

To protect the public water supply, City policies require precautions to be taken to isolate any contamination or pollution that may be present in consumer water systems which could backflow into the public water supply.

Rules and regs


Contact Us

Please report any suspected cross-connections to Water Distribution at 419-245-1825.

Frequently Asked Questions

What is a cross-connection?

Any physical connection created between a possible source of contamination and any public water system piping.

What is backflow?

The flow of water or other liquids or substances through a cross connection from a possible source of contamination back into the public water system. There are two types of backflow:

  1. Backpressure
    This occurs when water pressure generated from a private service exceeds the water pressure provided by the City’s water system. Causes for increased pressures from a private system may include a pump, elevated tank, boiler, or other condition.
  2. Backsiphonage
    This occurs when backflow is caused by negative or reduced pressure in the water supply piping.Cross-connections are the links between the public drinking water supply and auxiliary water such as a pond, holding tank or well. Backflows into the public water supply can be prevented with the installation and maintenance of Backflow Prevention devices.

How can a backflow occur?

When a cross-connection is created and a pressure reversal, either as backsiphonage or backpressure occurs in the water supply piping.

What is a backflow prevention device?

Any device intended to prevent the backflow of water from a customer water system to the public water system. These devices are typically installed close to the water meter.

Who can install/test a backflow prevention device?

A licensed backflow prevention contractor is required to install and test backflow prevention assemblies. Plumbing permits are required for performing this work.

What are some common potential backflow hazards?

  • Water operated sump pumps.
  • Hose connections to chemical distributors such as lawn fertilizer or herbicides.
  • Hose connections to a water outlet or laundry tub.
  • Lawn irrigation systems.
  • Swimming pools or hot tubs.
  • Boiler heating systems that are connected to the potable water supply.
  • Private water supplies such as wells.
  • Industrial or Commercial processes.

How can I reduce the potential for cross-connections and backflow hazards?

  • Eliminate any known cross-connections if possible.
  • Do not submerge hoses in tubs, pools, buckets.
  • Use hose bib vacuum breakers.
  • Use a backflow prevention device on a water operated sump pump.
  • Use a backflow prevention device on an irrigation system.