To: Honorable Mayor and Members of City Council
From: Joy Eldredge, Utilities Director
Prepared By: Chris Jones, Senior Civil Engineer
TITLE:
Title
Emergency Declaration for 36-inch Asbestos Cement Transmission Main Replacement
LABEL
RECOMMENDED ACTION:
Recommendation
Adopt a resolution (1) determining there is a need to continue the emergency action to execute and implement contracts for the construction to replace up to 11,000 linear feet of 36-inch asbestos cement transmission main; (2) approving a transfer in the amount of $11,000,000 from water CIP reserve fund balance account 531-35102 to CIP project account 53160139-63WT25UTER as documented in Council budget amendment No. 115; and (3) determining that the actions authorized by this resolution are exempt from CEQA
Body
DISCUSSION:
The City of Napa water system provides potable water to 86,906 persons throughout City of Napa and unincorporated Napa County. On the western side of the city, potable water is transported from the Barwick Jamieson Treatment Plant through a 36-inch asbestos-cement (AC) transmission main to the City of Napa service area. The 36-inch AC transmission main was installed in 1968 and is only 56 years old. Typically, an AC main would have a 100-year service life.
The main is critical to the City’s ability to convey water throughout the City, without the 36-inch transmission main, the City relies on the 24-inch steel transmission main on the east side of the City and smaller local distribution mains. Any further disruptions at the same time as a 36-inch AC transmission main break can cause major impacts and restrict the ability to provide water for large portions of the City.
Since 2020, the City has had nine main breaks on the 36-inch AC transmission main. Four of these breaks have occurred in the last six months. Previously the majority of main breaks were on the south side of Napa in open fields near the Napa Sanitation District. More recently the breaks have been occurring under pavement on Laurel Street and Old Sonoma Road. Historically there have been only two breaks under pavement in the 56-year lifetime of the pipeline. One of which was due to the 2014 earthquake. The types of breaks have also changed. Most of the breaks in the past were due to failures at the rubber gaskets on the collars that hold two pieces of pipe together. Two of the more recent failures had holes in the pipe wall rather than at the gasket. These main breaks are a concern because they damage the surrounding pavement, may take several days to months to repair depending on location, and release large volumes of water that may severely damage public and/or private property.
City Staff has determined that due to the increased frequency of breaks and more damaging leaks that the 36-inch AC transmission main needs to be replaced by 36-inch steel pipe. The extent of this pipe replacement is up to 11,000 linear feet of main located on the following streets:
• Linda Vista Avenue
• Robinson Lane
• Browns Valley Road
• Laurel Street
• Foothill Boulevard
Additional distribution system improvements may be required such as installing pressure regulating stations or replacing up to 1,000 linear feet of 12” or smaller mains that will be critical to continue service while sections of the 36” transmission main are out of service. These improvements are needed to allow the City to replace multiple sections of the 36” transmission main concurrently to return the transmission main back to service as efficiently as possible.
The City has current projects to pave Laurel Street and Browns Valley Road. The Laurel Street paving has been postponed until 2025 with temporary paving in place until final paving can be installed. The Browns Valley Road project is expected to start with concrete sidewalks in January 2025 and asphalt paving later in 2025. Due to these projects the main replacement is being prioritized on Laurel Street and Browns Valley Road. By prioritizing these streets, the City will realize cost savings by avoiding repairing leaks that cause greater damage when the road surface is sealed under new pavement or installing a new main in new pavement and then needing to repave after the repair or installation has been completed.
Emergency Determination:
On January 16, 2025, for the reasons summarized in this report, the City Manager determined that the 36-inch AC main replacement requires immediate action to resolve an emergency and authorized the Utilities Director to execute emergency contracts. (See Attachment 2.)
FINANCIAL IMPACTS:
A water fund CIP budget account 53160139-63WT25UTER is to be established for this project.
Funds in the amount of $18,478,149 are available in the CIP Reserve Fund Balance account 531-35102. Upon approval, a transfer in the amount of $11,000,000 will be made to account 53160139-63WT25UTER as documented in Council Budget Amendment No. 115.
CEQA:
City staff recommends that the City Council determine that the Recommended Action is exempt from CEQA pursuant to : CEQA Guidelines Section 15269 (Statutory exemption for emergency repairs, in accordance with California Public Resources Code Section 21080(b)(2)); CEQA Guidelines Section 15301 (Categorical exemption Class 1 Existing Facilities), which exempts repair, maintenance, or minor alteration of existing facilities involving negligible or no expansion of use; and CEQA Guidelines Section 15302 (Categorical Exemption Class 2 Replacement or Reconstruction), which exempts replacement or reconstruction of existing facilities on the same site and with the same purpose.
DOCUMENTS ATTACHED:
ATCH 1 - Resolution
EX A - Council Budget Amendment No. 115
ATCH 2 - Emergency Declaration for 36-inch Asbestos Cement Transmission Main Replacement
NOTIFICATION:
None