Posts

Mission Trails Water Project Completed; Park Trails Reopened

One of the San Diego County Water Authority’s large-scale capital improvement projects – the Mission Trails Flow Regulatory Structure II and Flow Control Facility (FRS II) – is now completed. The project upgraded the Water Authority’s untreated water supply system by improving the delivery of water to treatment plants serving the central and southern areas of San Diego County.

The FRS II project, which began construction in spring 2020, includes a new 5-million-gallon underground covered reservoir, a flow control facility and pipeline interconnections. The reservoir is covered with soil and vegetation, except for several access hatches and vents that allow for air movement inside the reservoir.

FRS II is the Water Authority’s second underground water tank located in Mission Trails Regional Park – the other one, located just west of the new one, is a treated water tank. The two tanks work to efficiently move water through the region, ultimately to customer’s homes and businesses.

“The Water Authority thanks the community for their patience while crews work to successfully build this important water delivery project,” said Michael Heu, the Water Authority’s construction manager for the project. “With the project completed, we are pleased to reopen the park trails which were previously impacted due to construction activity. The public’s safety was a top priority during this work.”

Boil Water Order for Tierrasanta, Low Pressure Elsewhere After Pipeline Breaks

The city of San Diego Monday issued a boil water order for around 600 residents of the Tierrasanta neighborhood due to low water pressure issues.

All affected customers will receive more detailed information at their homes. The affected area is largely around those streets adjacent to Mission Trails Regional Park.

New Water Tank in Mission Trails Nearly Complete and Will Soon Disappear

Construction of the new Flow Regulatory Structure II, or FRS II, in Mission Trails Regional Park is nearing completion. The structure is now completely enclosed on all sides and was successfully tested.

Construction crews have started placing soil around the exterior walls to begin burying the structure. In the next three weeks, the roof will be covered so the facility is concealed. Water is expected to begin flowing into FRS II in June 2022.

underground-tank-mission-trails

New Water Tank in Mission Trails Nearly Complete and Will Soon Disappear

Construction of the new Flow Regulatory Structure II, or FRS II, in Mission Trails Regional Park is nearing completion. The structure is now completely enclosed on all sides and was successfully tested.

Construction crews have started placing soil around the exterior walls to begin burying the structure. In the next three weeks, the roof will be covered so the facility is concealed. Water is expected to begin flowing into FRS II in June 2022.

Mission Trails Regional Park project

The new structure, located in the northwest portion of Mission Trails Regional Park, is part of a San Diego County Water Authority project to upgrade the untreated water system that delivers water to treatment plants servicing the central and southern areas of the county, helping to balance the flow of untreated water. Once in operation, the FRS II will be capable of holding nearly five million gallons of water – enough water to fill seven Olympic-sized swimming pools.

Area will be restored with natural vegetation

Revegetation efforts will begin after FRS II is work is complete this fall. The topsoil was removed and stored onsite and will be returned help restore native plants and vegetation to pre-construction conditions.

Before the project began, 225 pounds of live seed was gathered from within Mission Trails Regional Park and taken to a dedicated nursery. From these seeds, more than 22,000 native plants are being grown and will be planted over a 17-acre area. Once planted, there will be a 120-day plant establishment period followed by five years of maintenance and monitoring to assure successful implementation.

Construction began in March 2020 just as the coronavirus pandemic began. As an essential infrastructure project, construction on the water project continued during the pandemic.

The Water Authority operates and maintains a regional water delivery system capable of delivering 900 million gallons of water per day.

Watch a recent news story about the project nearing completion.

Update on Water Project in Mission Trails

Construction continues in Mission Trails Regional Park to upgrade the San Diego County Water Authority’s untreated water supply system. The estimated completion of the project has been extended from mid-2022 to late 2022 due mostly to necessary design changes. The project will improve the delivery of a safe and reliable water supply to treatment plants serving the central and southern areas of San Diego County.

FRSII-Mission Trails Regional Park-Trail Closure Map

Trail closures will continue Monday through Friday from 7 a.m. to 7 p.m. and reopen as soon as it is safe. The Water Authority’s work in Mission Trails Work will not affect the delivery of high quality drinking water to homes. Graphic: San Diego County Water Authority

For more information about the project including an interactive map showing the closed trails, visit sdcwa.org/mission-trails-FRS. Call 877-682-9283, ext. 7004, or email  with questions.

Water Authority Completes Pipeline 3 Relining in Mission Trails Regional Park

San Diego County Water Authority Operations and Maintenance staff recently completed a complex relining project on a section of Pipeline 3 in central San Diego, within Mission Trails Regional Park. Pipeline 3 traverses the western portion of the region from the Riverside County border in the north to Lower Otay Reservoir in the south. The proactive Pipeline 3 relining project is part of the asset management program to make preventative repairs to large-scale infrastructure.

Worker relines water pipeline

Water Authority Completes Pipeline 3 Relining in Mission Trails Regional Park

San Diego County Water Authority Operations and Maintenance staff recently completed a complex relining project on a section of Pipeline 3 in central San Diego, within Mission Trails Regional Park. Pipeline 3 traverses the western portion of the region from the Riverside County border in the north to Lower Otay Reservoir in the south.

Large-diameter pipelines operated by the Water Authority and its 24 member agencies extend approximately 310 miles to convey water throughout the region.

By relining pipes ahead of time or conducting timely repairs, the Water Authority and its member agencies avoid pipeline failures and improve the reliability of future water supplies. The proactive Pipeline 3 relining project is part of the asset management program to make preventative repairs to large-scale infrastructure.

Pipeline 3 Relining

In June 2020, O&M staff performed an inspection of Pipelines 3 and 4 within Mission Trails Park during a routine shutdown. They inspected an area of Pipeline 4 that had previously been repaired, and the repairs were found to have held up successfully. Pipeline 3 has similar characteristics to Pipeline 4 in that area, and during the shutdown, staff inspected and found a 32-foot section of pipeline that had sustained lining damage. Between August and September 2021, staff completed the complex repairs on Pipeline 3.

Operations and Maintenance teams collaborate, overcome challenges

“The project was challenging due to several geographical factors, including the distance of access structures from the damaged section and the steep grade of the hill that the section of pipeline traverses,” said David Hernandez, maintenance technician at the Water Authority. “Our asset management, facility maintenance, and mechanical maintenance teams collaborated closely to plan and execute the complex repairs.”

To begin the relining project, heavy concrete covers at access point structures were first removed to allow staff to access the pipeline. Piping and an air valve at the top and pumping well at the bottom of the hill were then removed to allow for safe access. Staff installed an atmospheric ventilation fan that moved fresh air into the pipeline. Once the piping and valves were removed, they were able to enter the pipeline.

Staff then hiked through the pipeline to perform a visual inspection and locate the damaged area. They located the broken lining section and loaded broken pieces into buckets and manually hauled the buckets to access structures. Then the metal pipeline was prepared for the application of new liner. Preparation of the pipe took several days – it involved carefully cutting out any remaining damaged liner, descaling rust from the metal, and cleaning up and wiping down the metal to prepare for new lining. O&M staff then mixed the new lining material – approximately 4,400 pounds of dry material was mixed and lifted over the course of the project. The new liner was then manually applied to the pipe, starting from the bottom half for traction and then applied up to the crown of the pipe. Finally, every inch of the new lining was carefully inspected.

Careful planning protects crews during critical repairs

The highly specialized work effort was performed in a safe and efficient manner due to careful planning and execution by the Water Authority’s O&M staff. Throughout the process, staff took multiple safety measures, including wearing personal protective equipment, having a confined space rescue team on standby, and tying hand and foot loops into a safety rope. The entire project took approximately one month. It will extend the lifetime of Pipeline 3, a crucial component to the region’s water supply.

Water Project in Mission Trails Park More Than 50% Complete

The San Diego County Water Authority’s Mission Trails FRS II water project is now more than halfway complete.

The project will upgrade the Water Authority’s untreated water system in Mission Trails Regional Park. When finished in 2022, the upgrades will provide more reliable water delivery to treatment plants that serve the central and south sections of San Diego County.

FRS II-water project-Mission Trails Regional Park-water infrastructure

Water Project in Mission Trails Park More Than 50% Complete

The San Diego County Water Authority’s Mission Trails FRS II water project is now more than halfway complete.

The project will upgrade the Water Authority’s untreated water system in Mission Trails Regional Park. When finished in 2022, the upgrades will provide more reliable water delivery to treatment plants that serve the central and south sections of San Diego County.

Construction began in March 2020 just as the coronavirus pandemic began. As an essential infrastructure project, construction on the water project continued during the pandemic.

The project includes construction of a new 5-million-gallon underground covered tank, flow control facility and pipeline connections. The largest component of the project is the building of the underground tank called a flow regulatory structure (FRS II) which will be used to balance flows in the aqueduct system.

Roof pour begins on water project

One June 11, the pouring of concrete to create the roof for FRS II began. FRS II will be the second underground water tank in the park – both work to efficiently move water through the region.

Construction efforts are also underway to build the new flow control facility. Once construction is complete, the work area will be graded to its previous contours and revegetated with native plants – many seeded from plants within the park itself.

New construction activities have begun about a half mile north of the FRS II. This most northern construction site will be used to connect the water flowing through the Water Authority’s pipelines to the FRS II.

Some trails closed for construction safety

To keep trail users safe, some trails are closed through early 2022 when work is complete. Signs are posted to clearly mark the closures, detours and provide a map to find alternative routes. In addition, the Water Authority created an interactive map showing the location of the closed trails. Go to www.sdcwa.org/mission-trails-FRS to view the map and learn more about the project.

Mission Trails FRS II water project construction

Construction crews formed and poured the walls of the Flow Regulatory Structure in December 2020. Photo: San Diego County Water Authority

Value of Water-Mission Trails-FRSII-Underground reservoir

Value of Water: Mission Trails FRS II

What does project do?

The Mission Trails Flow Regulatory Structure II Project, or FRS II, will be an underground concrete water tank in Mission Trails Regional Park that will store slightly less than five million gallons of water and be used to balance flows in the aqueduct system. FRS II will be the second underground water tank in the park – both work to efficiently move water through the region. Construction is underway and expected to be completed in 2022.

Why is this project important?

Improving the region’s water infrastructure ensures that San Diego County residents are getting a clean, safe, and reliable supply. The FRS II project is another example of the successful long-term strategy by the Water Authority and its 24 member agencies to diversify its water resources, make major upgrades in the regional water delivery and storage system, and improve water-use efficiency.

How do water ratepayers benefit?

The underground reservoir is being constructed within the park to improve the Water Authority’s untreated water system in the northwest area of the park. The upgrade will increase reliable water delivery to treatment plants that serve the central and south sections of San Diego County.

In 2013, the Water Authority finalized the Regional Water Facilities Optimization and Master Plan Update, the agency’s roadmap for infrastructure investments through 2035. This updated plan focuses on optimizing the Water Authority’s existing infrastructure while maintaining the flexibility to adjust to a range of future water supply needs.

Notable

Once complete, the dirt hill will be leveled to its previous contours and revegetated with native plants – many seeded from plants within the park itself. The reservoir will be completely underground – out of sight – but within the control of the San Diego County Water Authority.

Quotable

“The San Diego County Water Authority is building a massive 5-million-gallon concrete water storage tank, called a flow regulatory structure. You will never see it once it’s completed.” — Joe Little, Reporter, NBC 7, April 9, 2021.

[Editor’s note: This feature, the Value of Water, focuses on the projects, operations and maintenance by the San Diego County Water Authority and its 24 member agencies that increase the value, reliability, and safety of water for ratepayers in San Diego County.]