Mission Trails Flow Regulatory Structure II

Project Background

The Water Authority is building a new flow regulatory structure to upgrade the untreated water system in the northwest area of Mission Trails Regional Park. When complete, the project will upgrade the untreated water system that delivers water to treatment plants that serve the central and southern areas of San Diego County.

Standard construction hours are Monday through Friday, 7 a.m. to 7 p.m. with occasional 24-hour and weekend work. As a result, portions of trails in the western portion of the park are closed to public access. Trail closure signs and park maps showing alternate trails are posted to help park users navigate the trails.

A new underground flow regulatory structure, or covered reservoir, is being constructed to help regulate the water system’s flow of untreated water. It will be capable of holding up to five million gallons of untreated water. The facility will be covered with soil and vegetation, with the exception of access hatches and above-ground vents to allow for air movement in and out of the reservoir.

The work is part of a suite of projects called the Mission Trails Project located in the western portion of the park. In 2010, a new pipeline tunnel, removal of existing blue vent stacks and a new all-weather crossing of the San Diego River was completed. Construction of the flow regulatory structure portion of the project was planned to begin soon after but was delayed by the Water Authority’s Board of Directors in early 2011, citing increasing water rates due to lower water demands.

Trail Closures

Public safety is of the utmost importance during construction. To help keep trail users safe, certain trails in the western portion of the park are closed during construction hours, Monday through Friday, 7 a.m. to 7 p.m. Active construction sites are fenced and at these locations trail access is closed 24 hours a day, seven days a week through the duration of construction. Trail detour and closure signs with a trail map are installed on the trails to help hikers and bicyclists navigate the area. Closed trails will be reopened after construction.

Printable Map: Mission Trail Regional Park Trail Closures

Truck Traffic

Nearby residents will see an increase in construction traffic on Clairemont Mesa Boulevard, Calle de Vida, Portobello Drive and Antigua Boulevard as well as in and near the western portion of Mission Trails Regional Park. Construction vehicles will use park trails to access work areas. Truck drivers will be required to follow appropriate traffic rules as well as weight and speed limits.

School Information

Trucks will travel near certain Tierrasanta schools to access the western part of the park. Safety is the Water Authority’s first priority, and we want to help keep kids safe. During construction, please talk to your child about street safety. “Street Smart” posters providing street safety tips will be provided to schools near the access routes.

Project Status: Current

  • March 2020: FRS II construction starts
  • Early 2022: FRS II construction ends