Surface water from the Sacramento River would become Davis' new primary source of supply, with a few of the city's best wells providing summer surplus, through a project overseen by the Woodland-Davis Clean Water Agency. The new water intake would be just below the Interstate 5 overpass over the river, on the right. Courtesy photo


Cost should be No. 1 priority on water

By From page A11 | January 01, 2012

By John Munn

The Yolo County Taxpayers Association commends the Davis City Council for recognizing the need for a pause in the rush toward higher water rates. Whether we bring in surface water or not, the primary concern of the Taxpayers Association is affordability, and we hope that the design and cost of facilities needed to meet water quality and quantity needs of both Davis and Woodland can now be re-evaluated based what we can afford.

Water concerns in Davis and in Woodland are somewhat different. Davis may be able to meet the selenium standard imposed by the Regional Water Quality Control Board for treated waste water by mixing water from different wells, but the quantity of water available from deep wells being used to meet water quality standards might be limited by both aquifer capacity and UC Davis water rights claims.

The main constraint in Woodland is meeting water quality standards, and the city is currently being fined by the state board for exceeding the selenium discharge standard.

Use of surface water with much lower concentration of dissolved minerals, including selenium, could address the problems of both cities. Surface water is now available to Davis and Woodland based on rights to Sacramento River water that recently were granted by the State Water Resources Control Board following a multi-year approval process (for 47,000 acre-feet) and that are being purchased from the Conaway Ranch (for 10,000 acre-feet).

The larger, state-approved water allocation is junior to older rights, which would preclude taking water during dry periods when more senior rights holders are using all the available river supply, while the Conaway Ranch water right is senior to most other river water users.

These rights are hard to obtain, would be very difficult to replace, and when managed together should provide year-round access to river water during all but the most severe droughts. However, getting river water to Davis and Woodland will be expensive.

The current cost estimate for the proposed surface water project, in 2011 dollars and including administrative costs, is $337 million. This project would withdraw water from the Sacramento River by improving and adding pumping capacity to a reclamation district intake just upstream from the Interstate 5 bridge east of Woodland.

Water then would be moved across the Yolo Bypass in two pipes passing 80 feet beneath bypass levees to ensure levee stability and extending to a water treatment plant east of Woodland. After treatment, water would be transported in separate pipelines to Woodland and Davis, which have their own plans and costs for connection to and distribution through city water supply systems along with additional repair and maintenance costs.

The cost of a new water intake facility would be shared with the reclamation district and further reduced by already approved federal grants. The rest of the system would be paid for by Davis and Woodland water ratepayers to cover the costs of repaying construction bonds, purchasing the Conaway Ranch water rights, water treatment and delivery, and system maintenance.

Several elements of the current plan could use another look and/or more documentation. The use of two pipes from the water intake to the water treatment plant is proposed for 1) a continuing source of water should one of the pipes fail when repair work is delayed by flooding in the bypass and 2) sufficient flow velocity to reduce sediment accumulation.

However, conjunctive (combined) use of groundwater and surface water would allow wells to be used for emergency supply and decrease the amount of surface water required to meet city needs. Resulting reductions in required flow capacity could permit use of a single pipeline to reduce the cost of materials and excavation and cut the cost of boring under levees by nearly half, while still maintaining pipe flow velocities for sediment removal.

Another cost concern is the 80-foot depth requirement where pipelines pass under bypass levees. There is no disagreement that levee integrity is critically important, but it does seem odd that such a great depth would be needed to protect against seepage through fine-textured deposits in the Yolo Bypass area.

This depth requirement adds cost and the method by which it was determined should be made available for technical review.

The treatment plant is the most costly part of the surface water system paid for by Woodland and Davis. The total cost of this facility increases with required capacity, which could be reduced by additional use of ground water, as mentioned above.

Treatment plant construction also could be phased to avoid paying interest on capacity that is not needed now or in the near future. Greater reliance on existing wells also could reduce the size and cost of the pipeline projects needed to transport water from the treatment plant to Davis and Woodland.

A network of new pipes is planned to move surface water into the cities’ existing water systems. If complete surface water integration is not needed on the supply side to meet water quality standards on the discharge side, it may be possible to achieve savings by reducing the number of connection points.

However, this probably would result in different concentrations of dissolved minerals in water delivered to different service areas (which already occurs because of differences in water quality from existing wells).

A separate cost concern is the proposed design/build/operate (DBO) bid process being used to select a company to construct the surface water project. Altogether, this is a huge project and the operations component extends years into the future.

Few companies are large enough to undertake the combined design, construction and operation of such a large project, which includes several million dollars just to develop the design part of the bid. And the availability of bidders is further reduced by the small number of firms providing required operating services.

This has resulted in qualifying only three DBO bidders on the project, and it is possible that only two of these will submit a bid.

The DBO process makes the successful bidder responsible for cost increases from design oversights and future increases in operating costs. However, companies preparing bids are aware of these risks and account for them in their bid price, which means that risks will be paid for whether potential cost increases occur or not.

Breaking the project into smaller parts (intake, bypass pipeline, treatment plant, pipelines to cities, and such) would attract many, competing bids from local and non-local construction companies, which might lead to a lower combined cost.

Operating the system then could be put out to bid or assumed by the cities depending on cost projections and other considerations.

With the numerous concerns noted here and elsewhere in mind, an objective review of project alternatives should be conducted to ensure that bias for the proposed project does not influence the manner in which alternatives were considered.

There is also a governance problem with having the huge cost of a surface water project, plus past and upcoming costs of wastewater treatment plant upgrades, being imposed without recourse on the people of Davis, Woodland and throughout California by appointed members of State Water Quality Control Boards who cannot be held accountable by voters.

Local ratepayers can express their concerns about this situation by contacting the governor, who is responsible for making appointments to these boards.

The Yolo County Taxpayers Association hopes that these, and any other, suggestions for minimizing local ratepayer costs will be evaluated before further consideration of water rate increases. We recognize that not everything suggested here may turn out to be a cost savings or part of an optimal solution. However, all means of keeping water affordable need to be considered.

Residents of Davis and Woodland cannot afford to have their water rates tripled and doubled, respectively, as would be required to pay for the currently proposed surface water project.

In addition, this project must address real needs and problems. It is not acceptable to be paying more for the appearance of political correctness or, as should have been learned in elementary school, because of what other people are doing.

— John Munn, a Davis resident, is president of the Yolo County Taxpayers Association.

John Munn

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