Project Background

Section of Pipeline 4 at Lake Murray Reinforced with Steel Liners

The Pipeline Relining at Lake Murray Project relined approximately 5,400 feet of Pipeline 4 from the northern part of Lake Murray to the City of San Diego’s Alvarado Water Treatment Plant. The work also included decommissioning of the Water Authority’s Alvarado Hydroelectric Facility.

Construction crews conducted most of the work underground, inside the pipe, to avoid impacts to nearby homes and businesses. Water service was not interrupted during this work.

The pipe was accessed by excavating 45-foot areas, called portals. Once excavated, steel liners were installed within the existing pipe. Portals were surrounded by temporary wooden sound walls, where needed, to ease noise impacts to residents, comply with environmental regulations, and for security and safety precautions. The relining project was completed in 2017.