Revised_SOW_(11.8.24).docx

DRP-114 – City of West Sacramento, Well 22 Rehabilitation

SCOPE OF WORK AND MILESTONES

Under this Agreement, the Recipient shall rehabilitate a dormant well (Well 22) through repair and replacement of components as necessary and reintegrate it into the city’s distribution network.

Brief Project Description:

Well 22 is located between Oak Street and Harbor Boulevard in West Sacramento, California, on a 2.5-acre parcel of land. The city of West Sacramento is located in the Eastern part of Yolo County in California’s Central Valley. The project has coordinates of 38°35'16.6" N, 121°32'44.9" W. The Project is located on a parcel of property owned by the City of West Sacramento with adequate space to complete the well rehabilitation. Well 22 was once an integral part of the City’s water system and the Oak Street property already has a functioning water tank that the City currently uses in its water distribution system. Connection to this system will allow immediate supply integration for City water deliveries. Among the City's dormant wells, Well 22 was chosen for its strategic location and existing infrastructure. Its proximity to the North Area and the active tank site makes it an optimal choice for enhancing the reliability and redundancy of the City's water supply system.

West Sacramento’s water system serves 53,600 residents from a single surface water source – the Sacramento River – that is treated at the George Kristoff Water Treatment Plant (GKWTP). Historically, the city relied on groundwater as its sole source of water supply but transitioned to surface water in 1988. Because West Sacramento relies on a single source of surface water, there is currently zero redundancy in the system. Rehabilitation of Well 22 will allow the City to re-access groundwater resources to provide a reliable water supply to a disadvantaged community during drought conditions, like those experienced in 2022.

The City of West Sacramento is dependent on surface water supplies to serve the entire City. In 2022, the State implemented water rights curtailments and low water deliveries for the State Water Project and Reclamation reduced the Central Valley Project deliveries, and the Sacramento Valley took unprecedented cutbacks to senior contractors. There is a need for the City to develop an emergency back-up water supply that augments its existing water supply portfolio. The Well 22 Rehabilitation project will provide protection against a multi-year drought and natural disasters that could impact the current surface water supply.

The major components of the project include but are not limited to:

· Feasibility analysis and condition assessment of existing Well 22 to determine the condition of well casing, bore hole, drop pipe, and pump to determine what components need repair or replacement as part of this well rehabilitation process.

· Provide emergency backup water supply through well rehabilitation (based on feasibility analysis).

· Rehabilitating Well 22 by installing a new power drop and drop pipe, and repair/replace well casing as needed.

· Well bore hole, casing, drop pipe and pump repair and/or replacement as determined by the feasibility analysis.

· Installing pipes to connect the rehabilitated well to the City’s distribution system.

· Assessing the need for water treatment systems on this well, and implementing those systems, if needed

Purpose/Objective of Well 22:

Well 22 Rehabilitation Project will provide City residents, located in a disadvantaged and low-income area, with a reliable potable water supply during droughts. This Project will provide a dependable dry year water supply to these residents and provide the entire City with an additional backup water supply for health and safety service should the City’s primary surface water supply system break down.

The configuration of the City’s water rights and water contracts omit a small portion of the City’s service area in the northern section of the City boundary (“North Area”) creating a water supply vulnerability to a disadvantaged community in drought conditions. In short, the North Area does not have a fully reliable water supply to serve City residents in drought conditions.

The City’s water rights and contracts include an appropriative water right (Permit 18150), a Central Valley Project contract (CVP), and a water supply derived from the North Delta Water Agency (NDWA). Both Permit 18150 and the CVP supply serve the entire City during normal water supply conditions. The NDWA supply is the City’s only reliable drought water supply but this water supply may only be served in the NDWA service area that is south of the Union Pacific Railroad (UPRR) tracks. As such, the City’s North Area residents are inequitably deprived of reliable water supplies in drought conditions. The Project will remedy the inequity to the City’s low-income North Area, allay a drought year water supply vulnerability, and improve the City’s overall water security.

An urgent need for the Project exists because the City entirely relies on surface water (entitlements/water rights), which is vulnerable to drought conditions. There is a growing risk of water shortages for communities due to place of use limitations of the City’s NDWA entitlement, changes in climate, and new regulatory constraints. The Project will restore Well 22 and provide the City with additional groundwater supplies when the City’s surface water deliveries are insufficient.

The new well will eliminate the need for emergency response actions like purchasing emergency water supplies to serve the North Area. In addition, this Project will provide emergency and backup water supplies for fire protection should the City’s main surface water diversion and treatment facilities break down. This additional public safety benefit is valuable to all City residents.

Importantly, reactivation of Well 22 is the shortest and most efficient path to providing supplemental water to the City under drought conditions to the North Area that has inadequate dry-year water supplies. The most recent drought resulted in the state’s driest three-year period on record. This new climate reality requires all water providers to adapt to extreme conditions as California transitions to a hotter, drier, and variable future. In 2022, the City purchased emergency water supplies to serve the North Area when no City-controlled alternative water supplies were available. The Project will reduce the likelihood that the City will (a) drastically restrict water use in the low-income North Area while other areas in the City do not have the same water use restrictions; and (b) be forced to purchase scarce and expensive emergency supplies in future droughts to meet the North Area demands.

The City anticipates that the treated well water will be blended with the City’s treated water supplies from the GKWTP in the existing storage tank located at the well site. The level of treatment of the water required would need to be determined based on water quality samples taken after the well rehabilitation effort. Chlorine injection is anticipated at a minimum for residual disinfection, but other water quality constituents may require additional treatment such as a greensand type filter or simple ion exchange beds. Based on historic sampling, it is assumed that manganese levels may exceed secondary MCL levels and may require treatment.

Milestones/Tasks/Activities:

The milestones for completing the scope of work are:

Start Date Planned Completion Date

Aerial Maps

While the NDWA Contract was initially considered supplemental, during recent droughts, the City's CVP Contract and Permit supply were curtailed. Health and safety regulations require that if one part of the city faces restrictions, then the entire city must comply. As a result, the City had to spend a substantial amount on purchasing water from the open market for this area to alleviate the inequity and provide water to the North Area that is outside of the NDWA service area.

image1.png image2.png