| Time 12:00 P.M. to 1:30 P.M. Location Pasta's Tratorria 405 Main Street Pleasanton, California 94566 (925) 417 - 2222 |
Presentation
This presentation will describe the background and current design for the Penitencia Delivery Main and Penitencia Force Main Seismic Retrofit Project located at the Santa Clara Valley Water District’s (District’s) Penitencia Water Treatment Plant (PWTP) in the City of San Jose.
The Penitencia Force Main (PFM) is a 66-inch pipeline that conveys raw water from the District’s Central Pipeline to the PWTP for surface water treatment. The Penitencia Delivery Main (PDM) is a 60-inch pipeline that conveys treated water from the PWTP to the potable water delivery system. Both the PFM and the PDM are owned and operated by the District and were installed in District-owned right of way. A third pipeline, installed parallel to the PFM and PDM in the District-owned right of way, is the 72-inch South Bay Aqueduct (SBA), owned and operated by the California Department of Water Resources (DWR). This pipeline conveys imported (raw) water from the San Francisco-San Joaquin Delta (Delta) to the SBA terminal tank at the PWTP site.
This presentation will describe the background and current design for the Penitencia Delivery Main and Penitencia Force Main Seismic Retrofit Project located at the Santa Clara Valley Water District’s (District’s) Penitencia Water Treatment Plant (PWTP) in the City of San Jose.
The Penitencia Force Main (PFM) is a 66-inch pipeline that conveys raw water from the District’s Central Pipeline to the PWTP for surface water treatment. The Penitencia Delivery Main (PDM) is a 60-inch pipeline that conveys treated water from the PWTP to the potable water delivery system. Both the PFM and the PDM are owned and operated by the District and were installed in District-owned right of way. A third pipeline, installed parallel to the PFM and PDM in the District-owned right of way, is the 72-inch South Bay Aqueduct (SBA), owned and operated by the California Department of Water Resources (DWR). This pipeline conveys imported (raw) water from the San Francisco-San Joaquin Delta (Delta) to the SBA terminal tank at the PWTP site.
The SBA was constructed in 1964 as part of the State Water Project to convey imported water from the Delta to Santa Clara County. A segment of both the PFM and PDM, between the Piedmont Valve Yard and the overflow bypass structure, was constructed by DWR in 1964 in concert with the State’s project. The remaining segment of the PDM was constructed in 1972, at the time that the PWTP was constructed to serve the east side of Santa Clara County. In 1985, the remaining segment of the PFM was completed to serve as a backup source of raw water supply to the PWTP. The site of the PWTP, commissioned in 1974, was chosen because of the SBA terminal tank location as constructed by DWR. However, the PWTP site is located on a slow-moving landslide known as the Penitencia Creek Landslid. Furthermore, the Hayward Fault runs in a northwest to southeast direction approximately 1.2 miles to the east of the PWTP site.
Over the past 40 years of operation, the slow creep of the Landslide has impacted the structural integrity of the three pipelines. In 1983, the PDM failed due to compressive forces from Landslide movement, and caused flooding of nearby homes and erosion downslope of the failure. In 1985, the Penitencia Vault (Penvault) was constructed in the landslide portion of the pipelines’ alignment. It houses flexible expansion/contraction joint assemblies that were installed on all three pipelines. Based on the District’s ongoing monitoring data, the Landslide has been relatively stable over the past 40 years; however, there is a potential that a strong seismic event on a nearby fault could result in vertical and horizontal Landslide movement that would exceed the limitations of the existing pipelines and associated vault structures.
The objective of this Project is to perform a seismic retrofit of the PDM, PFM, SBA and if necessary, the Penvault and Finished Water Meter Vault (Meter Vault), to accommodate both the slow creep and potentially extensive seismically-induced movements of the Landslide. This Project would rehabilitate existing infrastructure to assure reliable water supply operations for the next 50 years.
The Project is currently in design and will include the following major items of work:
The Project is currently in design and will include the following major items of work:
- Replacement of about 800 LF of each of the three pipelines (PDM, PFM, and SBA) in the primary and secondary Landslide deformation areas. Greater understanding of seismic events, and technological advances in pipeline materials and installation over the past several decades, has produced earthquake-resistant pipeline components, also referred to as “Compression Pipe.” These components are part of the design for this Project.
- Demolition of the Penvault and flexible joint assemblies, as they will no longer be needed after installation of the Compression Pipe.
- Replacement of existing pipe beyond the primary Landslide deformation areas to facilitate transitions to the existing pipe and overflow bypass structure.
- Structural improvements to the Finished Water Meter Vault, which would include repairs to the concrete vault walls, replacing pipe supports, and reinforcing the 48-inch diameter thrust ring in the westerly wall.
- Transition structures between the new Compression Pipe and existing pipelines to the west; and
- Instrumentation to monitor both the new pipeline and landslide movement.
Karl Neuman
Karl is an Associate Civil Engineer with the Santa Clara Valley Water District (District) and is also the Project Manager for the Penitencia Delivery Main/Force Main Seismic Retrofit Project. Karl has been working for the District since 2002 focusing on Capital Improvement Projects for flood protection (i.e. levees, floodwalls, bridges, detention basins, and natural creeks) and water utility (i.e. pipelines, dams and water treatment plant facilities). Prior to coming to the District, he spent about 5 years working for geotechnical consulting firms. He is also registered as a civil engineer and geotechnical engineer in California. Karl is active in ASCE and has served on the San Jose Branch Board between 2010 and 2015.
Karl is an Associate Civil Engineer with the Santa Clara Valley Water District (District) and is also the Project Manager for the Penitencia Delivery Main/Force Main Seismic Retrofit Project. Karl has been working for the District since 2002 focusing on Capital Improvement Projects for flood protection (i.e. levees, floodwalls, bridges, detention basins, and natural creeks) and water utility (i.e. pipelines, dams and water treatment plant facilities). Prior to coming to the District, he spent about 5 years working for geotechnical consulting firms. He is also registered as a civil engineer and geotechnical engineer in California. Karl is active in ASCE and has served on the San Jose Branch Board between 2010 and 2015.