Title:                      Gird/Monserate Hill Water Line Replacement

Location:              Fallbrook, San Diego County, California

Contact Person:                Sherry R. Kirkpatrick, P.E.

Review Period: October 26, 2016 to November 28, 2016

Project Description:

The Rainbow Municipal Water District (District) proposes to replace the existing Gird/Monserate Hill water line located in the northeast quadrant of the Pala Road (SR 76) and Gird Road intersection. The District shut off the existing 2,150+-foot long water line several years ago due to a leak in the pipeline beneath a creek near Gird Road. Monserate Hills is currently served by a single pipeline in the Canonita Zone known as the Monserate Hill Pipeline. Following the installation of the new Gird/Monserate Hill water line the primary feed for Monserate Hills will be the Beck Zone and the Canonita Zone will serve the secondary feed.

The western 200+ feet of the existing water line would be replaced using a two foot wide open trench to remove the existing line and install a new line. The overall work area would be 20 feet wide, and the depth of trenching will vary depending on the topography, but the maximum trench depth is expected to be approximately five feet.

A Horizontal Directional Drill (HDD) entry pit would be excavated within an approximate 50-foot by 100-foot work area near the western end of the water line. The HDD pit will allow a tunnel to be bored 15 feet to 20 feet under the creek area which supports southern cottonwood willow riparian forest as well as under Diegan coastal sage scrub, both of which are regionally sensitive vegetation communities. A HDD exit pit would be excavated approximately 500 feet east of the entry pit. Use of the horizontal drilling technique will reduce impacts to regionally sensitive biological resources as well as any potential buried cultural resources in the project area. The existing 10-inch water line will be abandoned in place, and a 12-inch High Density Polyethylene (HDPE) water line will be installed in the bored tunnel.

The eastern 1,400 feet of the new 12-inch water line would be installed in a 24-inch wide open trench that would allow the removal of the existing water line and installation of the new 12-inch water line. The overall disturbance area would be 20 feet wide and 1,400 feet long. The depth of trenching will vary depending on the topography, but the maximum trench depth is expected to be approximately five feet.

Mitigated Negative Declaration:

In accordance with the California Environmental Quality Act (CEQA) and the CEQA Guidelines, Rainbow Municipal Water District has prepared a Draft Mitigated Negative Declaration (MND)/Initial Study (IS) for the Gird/Monserate Hill water line replacement project. Based on the IS, the District determined that the project would not have significant impacts on environmental resources, with the implementation of mitigation measures identified in the IS.

Public Comment Period:

October 26, 2016 to November 28, 2016

The public and all affected agencies are invited to review the Draft MND/IS and submit written comments. The Draft MND/IS can be viewed at the Fallbrook Branch Library, 124 South Mission Road, Fallbrook, CA. The document can also be downloaded below: 

Written comments are due by November 28, 2016 and can be sent to:

Rainbow Municipal Water District

Attn: Sherry R. Kirkpatrick, P.E.

3707 Old Highway 395

Fallbrook, CA  92028