will invite engineering firms to submit proposals to study whether the
Lower Ragged Mountain Dam
, built in 1908, can be safely raised 13 feet, despite the concerns of one City Councilor that the information may not be required for the community water plan.
Listen using player above or download the podcast:
said Tuesday he would prefer to wait on the study which could cost as much as $200,000 until the results of an ongoing dredging feasibility study for the
South Fork Rivanna Reservoir
“I think it’s an awful lot of money to be spending,” Brown said.
City Council is paying over $300,000
for a separate dredging study, which is expected to provide a cost estimate for removing sediment from the South Fork Rivanna Rreservoir.
However, City Manager
said issuing a request for proposals now would allow Council to proceed if it decides dredging would be a cost-effective way of increasing the water supply. If Council waits until summer to issue the RFP, information would not come back until 2011 because of the time it takes to award a bid.
“I don’t think you have anything to lose by going through this,” O’Connell said. “Some parts of this [study] you’re going to need absolutely in the decision process.”
The idea of raising the existing dam has been
championed by Mayor Dave Norris
, who claims a smaller dam could provide enough water to meet the community’s projected needs over the next fifty years if combined with dredging the South Fork Rivanna Reservoir.
Council chose to conduct the study itself
rather than have it performed by Schnabel Engineering.
Schnabel was hired last fall by the RWSA
to design a new dam at the
Ragged Mountain Reservoir
. The new dam was approved as a concept in the
2006 community water supply plan
and would raise the water pool by 45 feet inundating 180 acres of the Ragged Mountain Natural Area. Council felt having Schnabel perform both tasks would be a conflict of interest.
The request was amended by Council to require the winning firm to examine what steps need to be taken to simply repair the dam to satisfy state regulators. The dam is currently operating under a conditional certificate from the Department of Conservation and Recreation because of concerns raised in a 1978 inspection about the stability of an earthen buttress added in 1934 and the dam’s insufficient spillway capacity.
“If it’s not feasible to raise the dam by 13 feet and it is feasible to repair the dam, we’ll also have that investigated,” said Lauren Hildebrand, the city’s utilities director.
Bids will be received through the end of March.
A series of other studies regarding the community water supply plan will be completed this spring. Next week, the RWSA Board of Directors will hear reports on the feasibility of a concept to connect the South Fork and Ragged Mountain Reservoirs via a new pipeline. In early March, HDR engineering will hold a public meeting to explain the results of the first phase of the dredging study.