The District is making needed improvements to the water and sanitary sewer infrastructure. The District has approved the following Fiscal Year 2025‐2030 capital improvement water projects to increase the safety and reliability of the water system. Total cost: $13,168,326.
The current water projects include:
The District has approved the following Fiscal Year 2025‐2029 capital improvement sewer projects to increase the safety and reliability of the sewer system. Total cost: $4,690,000.
The current sewer projects include:
Skyline Tank Site Improvements
BACKGROUND: The Skyline Tank Site has an approximate 20,000 SF unpaved area between and behind the three storage tanks with a downward slope towards the westerly fence. The unpaved area is inaccessible when wet and requires additional maintenance for weed and erosion control. This project involves installing a retaining wall along the westerly fence, leveling behind the tanks and paving the area. These improvements will improve site access, simplify maintenance, and eliminate weed and erosion control issues.
BENEFITS: The Skyline Tank Site Improvements improves access, simplifies maintenance, and eliminates weed / erosion control issues.
Skyline Tank No. 3 Improvements
BACKGROUND: In February 2018 the District completed a condition assessment of Skyline Tanks (3 total) including coating inspections and structural analysis in the event of a 2,475-yr earthquake (2% chance probability of exceedance within a 50-yr period). The Skyline Tanks are the District's primary water storage facility and therefore essential to providing service, especially fire suppression, following an earthquake. Skyline Tank No. 3 retrofit recommendations include structurally retrofitting the tank's roof to withstand the design level earthquake at operating levels of up to 25 feet, shell strengthening/banding, and foundation improvements to mechanically anchor the tank. In addition, recommendations also include appurtenance upgrades including overflow relocation to exterior, ladders, guardrails, roof hatches, shell manholes, level indicators, center vent, sampling station, seismic valve, flush cleanout and a drain outlet. Work also includes a full recoat of the tank exterior and interior.
BENEFITS: The Skyline Tank No. 3 Improvements protects and extends the tank's service life, ensures tank integrity following the design level earthquake, provides tank isolation during a seismic event, and reduces water waste.
Skyline Tank No. 3
Skyline Tank No. 3 exterior walls are showing signs of corrosion from the wind and ocean. This project consists of recoating the interior and exterior of the tank, appurtenance improvements to increase tank reliability, and a new drain outlet.
PROPOSED IMPROVEMENTS
• Structural improvements to withstand the design level earthquake
• Recoat the entire tank exterior and interior roof
• Various appurtenance upgrades
PROJECT BENEFITS
The Skyline Tank No. 3 Improvements protects and extends the tank's service life, ensures tank integrity following the design level earthquake, provides tank isolation during a seismic event, and reduces water waste.
Skyline Tank No. 2 Improvements
BACKGROUND: In February 2018 the District completed a condition assessment of Skyline Tanks (3 total) including coating inspections and structural analysis in the event of a 2,475-yr earthquake (2% chance probability of exceedance within a 50-yr period). The Skyline Tanks are the District's primary water storage facility and therefore essential to providing service, especially fire suppression, following an earthquake. Skyline Tank No. 2 retrofit recommendations include structurally retrofitting the tank's roof to withstand the design level earthquake at operating levels of up to 25 feet and shell strengthening/banding. In addition, recommendations also include appurtenance upgrades including overflow relocation to exterior, ladders, guardrails, roof hatches, shell manholes, level indicators, center vent, sampling station, seismic valve, flush cleanout and drain outlet. Work also includes a full recoat of the tank exterior and interior roof.
BENEFITS: The Skyline Tank No. 2 Improvements protects and extends the tank's service life, ensures tank integrity following the design level earthquake, provides tank isolation during a seismic event, and reduces water waste.
Skyline Tank No. 1 Improvements
BACKGROUND: In February 2018 the District completed a condition assessment of Skyline Tanks (3 total) including coating inspections and structural analysis in the event of a 2,475-yr earthquake (2% chance probability of exceedance within a 50-yr period). The Skyline Tanks are the District's primary water storage facility and therefore essential to providing service, especially fire suppression, following an earthquake. Skyline Tank No. 1 retrofit recommendations include structurally retrofitting the tank's roof to withstand the design level earthquake at operating levels of up to 25 feet and jacking the center column to alleviate settlement. In addition, recommendations also include appurtenance upgrades including overflow relocation to exterior, ladders, guardrails, roof hatches, shell manholes, level indicators, center vent, sampling station, seismic valve, flush cleanout, and drain outlet. Work also includes a full recoat of the tank exterior and interior roof.
BENEFITS: The Skyline Tank No. 1 Improvements protects and extends the tank's service life, ensures tank integrity following the design level earthquake, provides tank isolation during a seismic event, and reduces water waste.
King Dr Improvements
BACKGROUND: Zone 3 is supplied water from the North Coast County Water District's (NCCWD) Christen Hill Tank located at the northeast corner of intersection of Glencourt Way, Skyline Blvd and King Dr. Although the tank is owned and maintained by NNCWD, the District has an agreement to use the tank for Zone 3 storage. To get water from the tank site to Zone 3, the District uses a combination of 24" and 12" pipe. The 12" asbestos cement pipe (ACP) water main portion is located in a cross country (CC) area within a few feet of San Andreas fault, with limited access and exact location unknown. This project abandons the existing 12" CC and installs a new 16" water main along King Dr using a combination of ductile iron pipe (DIP) and earthquake resistant ductile iron pipe (ERDIP).
BENEFITS: The King Drive Improvements eliminates a CC water main, improves water main accessibility, and improves seismic resiliency.
Christen Hill Tank Water Main Improvements
BACKGROUND: Zone 3 is supplied water from the North Coast County Water District's (NCCWD) Christen Hill Tank located at the northeast corner of intersection of Glencourt Way, Skyline Blvd and King Dr. Although the tank is owned and maintained by NNCWD, the District has an agreement to use the tank for Zone 3 storage. Water is moved into Zone 3 via a 24" transmission water main located within the tank's access driveway which crosses the San Andreas Fault approximately 800 feet uphill from the site entrance. Hydraulic modeling shows the 24" water main is oversized and can be replaced with a fully restrained and earthquake resistant 16" water main. This project will replace the existing 24" water main and install a combination of new 16" ductile iron pipe (DIP) and earthquake resistant ductile iron pipe (ERDIP).
BENEFITS: The Christen Hill Tank Water Main Improvements replaces an aging and oversized water main and improves seismic resiliency.
Inline Water Valves
BACKGROUND: The District is limited in isolating shorter sections of water main during shutdown operations due to existing valve locations. This project involves the installation of new inline valves throughout the system between pipe intersections and at intersections allowing the District to isolate smaller lengths of main for emergency repairs. This will also reduce the amount of residents affected by shutdowns.
PROJECT BENEFITS: The lnline Water Valves project reduces the amount of customer disruptions during repairs and emergency events.
Westborough Pump Station Improvements
BACKGROUND: Westborough Pump Station pumps water to the Skyline Tanks through Zone 2 but it is also designed to pump water to Zone 1 for a future Zone 1 tank. However, the area within the District boundary is fully developed and there is no land available for building any tanks making the additional Zone 1 piping at the pump station obsolete. This project will abandon the Zone 1 pipe configuration along with all its valves, check valves and pipes in the pump station and will create a extra space to be used as a storage area.
BENEFITS: Improvement of water quality by abandoning the Zone 1 pipes and improved flushing capabilities for the supply line.
Rowntree Pump Station Structural Analysis / Repair
Rowntree Pump Station is located along the northwest side of Gellert Blvd. directly across Rowntree Way. The pump station is a precast concrete structure built into the hillside with a concrete roof, rear and side walls dueling as retaining walls with the front exposed to the parking lot. There is also a wet well located directly behind the pump station between the building and sidewalk along Gellert Blvd. The pump station is accessed from the shopping center parking lot to the south. Over the years, the joint between the concrete roof and back wall has been leaking during rain events or when the wet well is full. It is also not known when the last structural analysis was performed on the building. This project involves performing a structural analysis of the building in addition to repairing the leak.
Rowntree Sanitary Sewer Lift Station
The valves are old and operation is becoming difficult and replacement is recommended. The Automatic Transfer Switch also requires replacement. The Rowntree Sewer Pump Station Improvements decreases the risk of pump failure and down time.
Avalon Sewer Pump Station Improvements
The Motor Control Center (MCC) panel and associated outdoor cabinet will be redesigned and replaced as they are in very poor condition. The Avalon Sewer Pump Station Improvements decreases the risk of pump failure and down time.
Westborough Sanitary Sewer Lift Station
The valves are old and operation is becoming difficult and replacement is recommended. Automatic Transfer Switch and Motor Control Center also require replacement. The Westborough Sewer Pump Station Improvements decreases the risk of pump failure and down time.
Appian Way / I-280 Easement Sanitary Sewer
BACKGROUND: The Appian Way / 1-280 sanitary sewer alignment (±2,260 LF of 6"-10" vitrified clay pipe (VCP) and cast iron pipe (GIP)) is the sole trunk line for collecting sewage from the southeastern portion of the District and is a critical system element. The alignment is nearly 100% within cross-country terrain beginning near the Appian Way / Valley View Ave intersection, extending down steep terrain towards 1-280 and then running parallel with 1-280 before terminating at the Westborough Pump Station. In 2017, CCTV video determined the pipe showed a high frequency of internal defects as shown on the map - with some very severe. The City of Daly City also identified this alignment for replacement given access difficulties and consistent maintenance. Although some sections of main have minor defects, all pipe should be replaced holistically. This project replaces the existing sewer main in addition to replacing/rehabilitating manholes. For budgeting purposes, this project assumes open-trench construction and replacement with polyvinyl chloride (PVC).
BENEFITS: Replaces 2,260 LF of deteriorating sanitary sewer main greatly reducing future maintenance and extending overall system life.
Westborough Pump Station Bypass
BACKGROUND: The Westborough Pump Station is located along Westborough Blvd next to the Westborough Water District office. It is the only sanitary sewer pump station owned by the District that currently has no bypass. A sewer bypass for the sewer pump station is critical for easier sewer pump and valve maintenance and repair. Not having the bypass significantly increases the cost of any repair.
BENEFITS: A bypass connection will make any repair easier and significantly decrease the repair cost.
Gellert Blvd. / Archdale Ct. Sanitary Sewer
BACKGROUND: The City of Daly City identified portions of sanitary sewer main along Gellert Blvd and the Archdale Ct area (paralleling Westborough Blvd) for replacement due to known and consistent maintenance issues. The sewer mains consist of 6" vitrified clay pipe (VCP) - 260 LF along the Archdale Ct homes and ±1,300 LF along Gellert Blvd. In 2017, CCTV video determined the pipe showed a high frequency of internal defects as shown on the map - with some very severe. Although some sections of main have minor defects, it is recommended all pipe be replaced holistically. This project replaces the existing sewer main in addition to replacing/rehabilitating laterals and manholes. For budgeting purposes, this project assumes open-trench construction and replacement with polyvinyl chloride (PVC).
BENEFITS: Replaces ±1,560 LF of deteriorating sanitary sewer main greatly reducing future maintenance and extending overall system life.
Westborough Pump Station MCC Upgrades
BACKGROUND: The Westborough Pump Station is a critical pumping facility taking sewage from the lowest part of the District and pumping it uphill to Rowntree Pump Station. From the Rowntree Pump Station it is then pumped further uphill until it gravity feeds into the City of Daly City's sanitary sewer system. The City of Daly City indicated the existing motor control center (MCC), essentially the electrical infrastructure needed to power/control the pumps, has reached it's service life where replacement components are not readily available. This project replaces the entire MCC with new modern materials and equipment.
BENEFITS: Replacing the Motor Control Center will ensure the pump station continues to operate as designed without major complications due to outdated replacement parts.
Rowntree Pump Station MCC Panel Upgrades
BACKGROUND: The Rowntree Pump Station is a critical pumping facility taking sewage from the middle part of the District and pumping it uphill until it gravity feeds into the City of Daly City's sanitary sewer system. The City of Daly City indicated the existing motor control center (MCC), essentially the electrical infrastructure needed to power/control the pumps, has reached it's service life where replacement components are not readily available. This project replaces the entire MCC with new modern materials and equipment.
BENEFITS: Replacing the Motor Control Center will ensure the pump station continues to operate as designed without major complications due to outdated replacement parts.
List of Future Potential Capital Improvement Projects
A list of future, potential water capital improvement projects can be downloaded here (PDF).
A list of future, potential sewer capital improvement projects can be downloaded here (PDF).
The District is working on conducting a Rate and Fee Study to address these long lists of about $38 million worth of potential water projects and about $43 million worth of potential sewer projects. Currently, the District has been working on the most important projects first, using the "Pay-As-You-Go" Budget Rule to pay for these projects. The District is assessing the need to accelerate the Capital Improvement Program and looking for ways to finance them.