Project Details

Project Type:	Open Trench and HDD Project
Location:	Watsonville, CA.
Owner:	Pajaro Valley Water Management Agency (PVWMA)
Engineer:	CH2M Hill Engineers
Contract Value:	$17,791,160
Contract Type:	Public Development
Completion Date:	June 30, 2008

Project Highlights:

• Installation of approximately 52,00 LF of Welded Steel Pipe(WSP)
• Pipeline diameters ranged from 6” to 36”
• Numerous appurtenances (blow-off’s, air valves, isolation valves,
      irrigation turnouts and cathodic protection)
• Two 54” steel casing tunnel crossings under State Coast Highway 1
• 36” heavy-wall WSP (HDD) crossing under the Pajaro River 1,300 LF in length
• Flow-meter assemblies that include electrical instrumentation and control features
• Significant pavement replacement, traffic control and trench de watering systems
• Construction transgressed through hundreds of active table crop acres growing strawberries,
     brussel sprouts, artichokes and similar varieties of food products

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Downloads:

Coastal Distribution Survey Results Map

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The PVWMA is a state-chartered water management district formed to efficiently and economically manage existing supplemental water supplies used for crop irrigation. PVWMA determined that a pipeline distribution system was needed to deliver usable irrigation water, reduce seawater intrusion and to minimize groundwater pumping near the coast. This pipeline system is called the Coastal Distribution System (CDS) and was constructed in two phases.

Phase I

The first phases of the CDS have been constructed over the last five years on the Santa Cruz County side of the Pajaro River. These pipelines could now supply water to about 2,000 acres in the agriculture areas most impacted by seawater intrusion. This section of the project could easily be connected to the Harkins Slough Project.

Phase II: CDS 2006-07 Construction Project

The next portions of the pipeline will serve lands in Monterey County south of the Pajaro River. In order to get the pipeline to the south side of the river, Horizontal Directional Drilling (HDD) was used by MCI. A 1,500-foot long bore-hole was installed on a curve, up to 50 feet below the river bottom. The 36-inch diameter steel pipeline was welded in sections at the surface and pulled back under the river after the initial bore was complete. There was no disturbance to the river bottom.

Now with water delivered to the south of the Pajaro River, the CDS pipeline system was expanded by MCI to supply an additional 2,000 acres of crop irrigation water. The Agency has long terms plans to expand the system to possibly service an additional 3,000 acres, but about 18,500 acres of coverage would be needs to halt seawater intrusion. Thus, the CDS pipelines and Harkins Slough Project, will not provide a total solution.

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Articles & News

Coastal Distribution Survey Results Map

CDS project construction of the two phases can be see on the following survey map.
Download pdf (95KB) here

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