Water authorities agree on phased construction for earthen dam

By Brian Wheeler

Charlottesville Tomorrow

Tuesday, March 8, 2011

The remaining two bodies with authority over the community’s 50-year water supply plan held separate special meetings Tuesday to endorse the phased construction of a new earthen dam at the

Ragged Mountain Reservoir



Albemarle County Service Authority

and, then later in the day, the

Rivanna Water and Sewer Authority

both voted in favor of the new dam. The first phase will raise the existing reservoir pool by 30 feet, and an oversized foundation will support a future 12-foot increase if conditions indicate it is needed.

A Feb. 22 vote

by Charlottesville’s City Council to endorse an earthen dam, breaking a stalemate that had been reached with Albemarle County, has triggered a cascade of dominoes that now has all “four boards” once again behind the same water plan.

Gary O’Connell

, the ACSA’s executive director, presented his board with a draft resolution of support, which it adopted unanimously.

“This resolution also acknowledges that our board of directors still has a preference towards a 42-foot pool height [increase] and a dam of size to accommodate that,” O’Connell said. “But recognizing that our partners have agreed to be in a different place, [this resolution] looks at phasing.”

O’Connell noted that the ACSA resolution made specific references to the need for triggers that would lead to construction of the dam’s second phase.

“For phase two, which would be the raise from 30 to 42 feet, we [support the development] of some fixed and objective threshold that’s based on urban system demand and safe yield — in other words, the use that’s in the system over time,” O’Connell said.

Some county officials continued to express their disappointment Tuesday that the dam would not be built to its full height all at once. According to the RWSA, the added useable water volume for a 30-foot rise is 63 percent of the volume of a 42-foot rise.

“I think everybody on this board is very disappointed that we are getting 40 percent less water storage for the same price,” said

Liz Palmer

, a member of the ACSA board. “But we do recognize that the city has made a big step here.”

In January,

Thomas L. Frederick, Jr.

, executive director of the RWSA, said that from this point forward a full-height earthen dam would cost between $24.8 million and $28.4 million to complete.

Schnabel Engineering

, who is completing the design of the dam, said that 99 percent of the cost of a full-height dam would be expended to build just the first 30-foot phase.

At its meeting, the RWSA board authorized Schnabel to make adjustments to the final design of the dam to accommodate the phased approach. Frederick said the changes would cost an additional $28,500 and add 10 days to the schedule.

Frederick told his board that the dam’s design should be completed by April 29, the same day as a

deadline set by the Virginia Soil & Water Conservation Boar

d. In the meantime, Frederick said his staff is busy submitting modifications to state and federal water supply permits to reflect the changes.

Negotiations are continuing between the city and the county on the cost-sharing arrangements for the almost $140 million water plan, which includes not only the dam, but a new pipeline connecting Ragged Mountain to the

South Fork Rivanna Reservoir

, as well as upgraded water treatment facilities.


David Brown

said the community should move forward “expeditiously” while allowing time for continued input.

“We should move forward in a fashion that council has a chance to discuss and review, and the public has a chance to have an input on, for example, what a trigger would be,” Brown said. “That would be something that a lot of people would have some interest in making sure was transparent and thoughtful.”