Lawn Irrigation System Requirements

All lawn irrigation systems require a cross connection device to prevent the backflow of water from the lawn irrigation system into the structure’s potable water system. This is to ensure that contaminants from outside sources (e.g. fertilizers) do not enter the drinking water in the structure. A Plumbing Permit and inspection are required for the backflow prevention device for Commercial applications. A Limited Service and Repair Permit and inspection are required for Residential applications.

Examples of approved backflow prevention devices:

  • ASSE 1001 V. B. or CSA B64.1.1 atmospheric-type vacuum breaker
  • ASSE 1020 P.V.B. or CSA B64.1.2 pressure-type vacuum breaker
  • ASSE 1013 R.P.Z., AWWA. C511, CSA. B64.4 or C.S.A. B64.4.1 reduced pressure principle backflow preventer.

Special Notes:

  1. A valve shall not be installed downstream from an atmospheric vacuum breaker.
  2. If chemicals (i.e. antifreeze) are used to winterize the lawn irrigation system, the ASSE. 1013 RPZ is the only approved backflow prevention device.

All residential lawn irrigation systems must be installed only on private property of single family homes and NOT within the right-of-way dedicated for public street purposes. If lawn irrigation systems are located within the state right-of-way they shall be removed at the owners' expense prior to acceptance of streets into the state system. Installation of irrigation systems that fall in the right-of-way will result in unnecessary expense to the homeowner, and a delay in the acceptance of streets.

See Building Development's Policy & Procedure 4.5.2 Water Meter Crocks for more information.

If you have any questions regarding obtaining a Commercial permit, contact the Prince William County Department of Development Services Plan Review Office at 703-792-4040. If you have any questions regarding obtaining a Residential permit, contact the Prince William County Department of Development Services Permits Office at 703-792-6924.

Generally the street right-of-way limit is one of the following:

  • One foot behind the sidewalk for streets with curb and gutter
  • Seven and one-half feet behind the curb for streets with curb and gutter but no sidewalk
  • 15 feet from the roadway pavement on streets with ditches

Note that the above limits are guidelines only. Installation must be in accordance with the property/right-of-way line shown on the approved record plat.

Always dig with C.A.R.E. - Contact Miss Utility before you dig - it's the law! Dial 811 or call 1-800-552-7001 for ALL excavation work ANYWHERE in Virginia.

If you have any questions regarding right-of-way, contact the Prince William County Department of Transportation at 703-792-6825 or the Virginia Department of Transportation at 703-383-8368.