Collaboration ensures successful relining project in North County
Realignment of State Route 76 in North County and the associated relining of sections of Pipelines 3, 4 and 5 put Water Authority crews to the test during the winter and spring. Collaboration by several departments, member agencies, the Metropolitan Water District of Southern California and Caltrans ensured that all water demands by member agencies were met and all facilities operated as designed.
The complex, multi-stage relining resulted from the final phase of a Caltrans project to widen and realign State Route 76 between Interstate 15 and South Mission Road in Bonsall. The work directly impacted the three pipelines comprising the Water Authority’s Second Aqueduct.
Caltrans agreed to spend $6.1 million relining Pipelines 3, 4 and 5 within the Second Aqueduct right of way, extending the life of those sections by 75 years. However, the project included a series of shutdowns that severely limited water entering the county and required unique operational adjustments. Those accommodations included storing more than 35,000 acre-feet of water in San Vicente Reservoir for delivery when the pipelines were out of service, and using the San Vicente Pump Station for the first time to meet operational demands.
As a result of careful planning and execution, there were no water supply interruptions to the Water Authority’s member agencies. The project was completed in March.
Nob Hill Improvements Project advances
Following certification of the final Environmental Impact Report for the Nob Hill Pipeline Improvements Project [1]in June 2014, the Water Authority continued to hold numerous public meetings for residents in Scripps Ranch in preparation for the start of construction in late 2015.
The project includes replacing two existing pipelines with one pipeline at a lower elevation and a new access road for maintenance crews. Once completed in 2017, the work will improve aqueduct hydraulics in the area, reducing the potential for pipeline damage. In addition, the new road will mean that Water Authority vehicles won’t need to use Scripps Nob Hill roads for accessing agency facilities, a long-term benefit for the community.