Raw sewage pump replacement

Learn about the raw sewage pump replacement project at West Point to replace the plant’s aging pump system and make seismic improvements to the building that holds the pumps.

Project update

West Point readies for new pump system to replace its aging ‘heartbeat’. May 2025

Project description

The raw sewage pump system at West Point was built in 1966 with the original facility. The original system uses 4 pumps to meet the needed capacity. Pumping untreated combined sewage over a long time has resulted in significant wear on the pumps. In addition, the system could fail during an earthquake due to its age.

The purpose of this project is to replace the raw sewage pump system at West Point and implement structural improvements to the facility that holds the pumps.

Project benefits

This project will improve both the pump system at West Point and the building that holds the pumps.

Replacing the pump system at West Point will build redundancy in the pump system. The current system needs all 4 pumps to meet maximum capacity needs and does not have capacity to handle potential overflows. The new system will only require 3 pumps of the 4 pumps to meet maximum capacity needs. The maximum capacity for the system can still be handled even if 1 pump needs maintenance.

This project will also make seismic improvements to the pump building structure in the event of an earthquake.

Project schedule

The project began in 2024. It will take approximately one year to replace each of the four pumps. Construction will last approximately five years, through 2029.

2024
- Construction equipment staging begins.
- Initial demolition and abatement of sections of the RSP building starts.
2025
- Demolition and abatement work continues.
- Relocation of existing utilities and installation of new utilities for new pumps begins.
- A new bridge crane will be installed.
- Demolition of breakroom, bathroom, day room.
- New battery room constructed.
- Structural seismic upgrade work begins.
2026
- First pump and engine are replaced with new pump and electric motor.
- New electrical equipment and controls installed.
- New breakroom, bathroom, and day room constructed.
- Structural, electrical, piping, and control modification made for first pump.
2027
- Second pump and engine are replaced with new pump and electric motor
- Rehabilitation of morning glory and pump discharge for second pump
- Structural, electrical, piping, and control modification made for second pump
2028
- Third pump and engine are replaced with new pump and electric motor

Community impacts and outreach

The County anticipates that impacts to the nearby community during construction, such as noise, will be minimal as construction will take place inside the treatment plant walls.

We will provide ongoing updates on our website as the project progresses. Sign up for email or text updates for current West Point Treatment Plant capital improvement projects below.

Project documents

Project FAQ sheet, February 2025

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Frequently asked questions

The purpose of this project is to replace the Raw Sewage Pump system and implement structural improvements to the facility.

The Raw Sewage Pump system was built in 1966 with a capacity of 440 million gallons of wastewater and stormwater per day (MGD). The system uses four pumps to meet the needed capacity. When the treatment plant was upgraded in 1988, the pumps were not upgraded. While the capacity remained at 440MGD after the upgrade, pumping untreated combined sewage over a long time has resulted in significant wear on the pumps. The cost to keep the system reliable has significantly increased due to the maintenance and repairs required to keep the pumps in service. In addition, the system could fail during an earthquake due to its age.

Replacing the pump system will build redundancy in the system, meeting the needed capacity even if a pump needs maintenance.

The current system needs all four pumps to meet the maximum capacity while the chosen alternative for the new pump system will only require three pumps, making maintenance much easier.

The existing pump system is engine driven which requires the use of gas. The new system will be driven by electric motors, reducing the need for gas at the plant.

This project will also make improvements to the building structure to make it more reliable during a potential earthquake.

The current system will be replaced with four new pumps driven by four electric motors. Only three electric motors will be needed to meet West Point’s 440 million gallons per day (MGD) capacity. This allows West Point staff to work on a pump without reducing the plant’s capacity and have a pump available in case another pump needs maintenance.

Minor construction activities began in 2024. Construction is expected to last five years, until fall of 2029.

The plant must remain operational every day of the year. This makes this project complicated. One pump and its associated engine will be replaced by a new pump and electric motor at a time to maintain West Point’s ability to treat incoming wastewater. Most major pump work will be completed in the summer months when wastewater flows are lighter.

Additionally, there will be major electrical and structural work to the building housing the raw sewage pump system. This will ensure the new facility meets current earthquake building standards.

$216 million. The Wastewater Treatment Division was able to acquire a low interest loan from the EPA for nearly $110.3 million of the project’s cost.

The biggest impact anticipated at this time is the presence of a large crane. The crane will be onsite to help move equipment in and out of the raw sewage pump building.

All other construction will take place behind and below West Point’s walls.

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