Encroachment Policy

1.0  Purpose:

The purpose of this policy is to establish guidelines for the protection of District-owned underground infrastructure.  Specifically, this policy is intended to protect the underground BMID-owned pipe valves, fittings and appurtenances but also the private property through which these easements run by establishing standard dimensions of easements and bury depths (depth of cover) over the pipe distribution systems. (RCW 58.17.310)

2.0  Definitions:

Encroachment is defined as any placement or construction of a permanent structure or excessive excavation or filling on the existing grade within a BMID pipe easement: A permanent structure is defined as a house, garage, shop, tennis court, underground swimming pool, keystone block or structural concrete blocks or walls, underground fish pond/waterfall feature, wood decks, or large structural pergolas requiring embedded treated wood columns. The planting and placement of large trees, shrubs or hedges will also not be allowed within BMID easements without prior approval from the District. Exempt structures or items are defined as City or County Roads, private driveways generally perpendicular to the easement, decorative curbing crossing the easement, corrals and fences and other buried utilities crossing under or over the District’s easement and pipeline.

Easements are defined as narrow strips of land designed and recorded on all lots, blocks or parcels of land that provide for the routing and placement of underground utilities.

All BMID underground pipe, valves, fittings and appurtenances shall be protected on all sides by an easement. Specifically, underground pipe, valves and appurtenances shall be situated horizontally and vertically within either a 10-foot or 20-foot wide easement depending on the size and type of pipe. (See 5.0 below)  An easement allows for the unencumbered ingress and egress of District personnel for the purpose of the operation, maintenance, modification, inspection and repair of these various District-owned assets.

Depth of cover means that distance from the finish grade to the top of pipe. Horizontal dimensions of pipe cover vary according to the diameter and type of pipe. (See Fig. 1).The minimum and maximum depth of cover is defined in Sections 4.0- 5.0.

3.0  Procedure: These standards shall become part of the BMID Standard Construction 

      Standards for both the Irrigation and Domestic pipe distribution systems.

4.0  Standard Dimensions: Easements / Depth of Cover

All BMID easements are either 10-feet wide or 20-feet wide.

Ten foot wide easements are reserved for sub-main, water distribution piping typically along residential lot lines or within public street right of ways.. Typical pipe sizes within these easements shall be from 1-inch to 12 inch diameter. There are some exceptions were larger diameter pipe is allowed.

Twenty-foot easements are intended for large diameter, high-pressure distribution/transmission mains (typically irrigation).

These distribution mains are high pressure, larger bore pipe ranging in size from 6-inch to 48-inch diameter. Pipe material is welded steel.

Depth of Cover:

The minimum depth of cover over a BMID domestic water line is 4.0 feet. (48 inches)

The minimum depth of cover over a BMID irrigation pipe is 2.5 feet. (30 inches)

The maximum depth of cover for any pipe is 5.0 feet. (60 inches).

The minimum lateral distances (protective pipe envelope) of backfill for each pipe is shown in Figure 1.  These distances are measured from the point of tangency from the outside of the pipe wall.

Note:  Minimum depth of cover underneath street varies according to jurisdiction. (City of Richland or Benton County Public Works)


5.0  Pipe Classifications:

         High Pressure Distribution Main (100-250 psi)

         Material:  Welded Steel, 6”- 48” diameter

               Service: Irrigation

               Standard Easement Width: 20-feet

               Reduced Pressure Sub-Mains (60 – 110 psi)

               Material: PVC, 2” – 14” diameter

               Service: Irrigation and Domestic

   Standard Easement Width: Either 10-foot or 20-foot depending on pipe size and


               Transmission / Distribution Mains

               Material: PVC / Asbestos-Cement, 6” – 12” diameter

               Service: Domestic

               Standard Easement Width: 10-feet

               Service Lines

               Material: PVC, Copper or HDPE Poly 1” – 1.5” diameter

               Service: Domestic

               Standard Easement Width: 10-feet

6.0  Figure 1 (Attached)

Adopted by the Board of Directors of the Badger mountain Irrigation District, Benton County Washington at a regular open meeting on the 7th. Day of August 2013.


     Badger Mountain Irrigation District

87525 E. Reata Rd, Kennewick, WA 99338
Phone: (509) 628-0777