Washington is an unincorporated community located in Nevada County, approximately 13 miles east of Nevada City, on the South Fork of the Yuba River. The community is small and isolated, with few opportunities for expansion due to wild and rugged watershed lands, surrounded entirely by Tahoe National Forest property. Washington is also a popular recreation destination, which results in considerable spikes in summertime water use.
Washington was initially settled as an active gold mining community in the 1850s. The water collection and delivery system designed during that era served as the basis for subsequent infrastructure design. The Washington water treatment and distribution systems are very basic, utilizing gravity flow and a sand-filter/chlorination treatment to provide treated water.
The Washington County Water District (WCWD) is the only water agency serving the community. The district provides water through 122 hook-ups that serve approximately 140 residents and businesses, including two campgrounds and a bar/hotel.
The Problem
The infrastructure that serves the district is aging and was installed prior to development of modern conservation standards, with much of the piping and distribution system dating from the mid-to-late 1800’s. The current system collects water from Canyon Creek via a small impoundment created by a diversion dam located near the creek’s convergence with the South Fork of the Yuba River. Water is piped using gravity flow through a 4-inch-diameter PVC line to the slow-sand filter and chlorination system housed on Maybert Road. Treated water is then piped three miles to a storage tank, following the alignment of the original wooden flume that served the District from the 1860s through the mid-70s when the line was replaced with a PVC pipe system. Residents along Maybert Road, which parallels the alignment, receive their water via lateral connections to the main distribution line.
The distribution system operates entirely via gravity flow with one storage tank serving the entire system. The lack of sufficient local/on-site water storage is especially problematic during peak water use. The storage tank currently spills considerable amounts of water during high-demand summer months, due to outdated technology. The main and lateral connections in the town of Washington are currently poorly mapped and the loss through undetected leaks is likely to be considerable, though currently undocumented.
As a disadvantaged community, Washington has not had the resources to map its infrastructure system, conduct systematic leak detection and repair activities on its aging pipelines, upgrade water storage and distribution systems, engage in community-level water conservation, or meter any portion of its system. The district has almost no capacity to adapt to low-flow scenarios. Additionally, residents are not financially able to retrofit aging plumbing.
The district currently lacks a method for monitoring water use, as opposed to the amount of water treated, so WCWD has no way to locate or repair system leaks, whether large or small, nor do they have the ability to conduct residential water audits. In addition, the absence of a high headwater storage facility and/or pump-supported water distribution system has resulted in below-standard water pressure across the higher elevation portions of the system. Irrigation efficiency strategies and hardware have not been provided to the community, leaving local residents unable to improve the peak summer water demands.
Finally, the design and installation of the various WCWD improvements has been delayed due to three critical factors: the retirement in summer 2013 of the engineer who prepared the initial design concepts and estimates for the grant proposal, and the deaths of both the WCWD Operations Manager (John Stark, August 2012) and the long-time Board President (Don Edgman, December 2013).
The net effect of losing these key individuals has been: loss of specific technical knowledge of the system and its operation and components; the need to locate an engineering company and accommodate its timeframe to learn the system; reevaluation of the system components as proposed to ensure that the installed improvements will function as described in the grant; recruitment and hiring of a new Operations Manager (OM) for the District (and allowing adequate time for new OM to fully understand the system to allow for full participation in the review and design of all project components); and, ensuring that the project components (Project # 9 – 14) are holistically evaluated and the resulting infrastructure improvements are designed in response to this holistic evaluation.
As a result of these factors the entire WCWD suite of projects was systematically reevaluated. In several cases, this resulted in an alteration of the project design methodology or approach, or technical specifications, though with no change in the final deliverables.
The Solution
This project package includes a comprehensive water conservation and infrastructure improvement plan with the following components:
# 9 – Maybert Road Transfer and Distribution Line Replacement
# 10 – Relief Hill Road Flow Control Pressure System Improvements
# 11 – Level-Control Altitude Valve Improvements
# 12 – System-Wide Installation of Water Meters
# 13 – Downtown Leak Detection and Repair
# 14 – Comprehensive Water Conservation Planning Program