Dredging 101: $25-$30 million
Until a few months ago, dredging had all the glamor of using diesel equipment to pump mud off a lake bottom. Which of course is what it is.
"Dredging is a fancy word for digging dirt underwater," said one of the suits, Chris Gibson. By the end of the evening, the Wilmington, Delaware-based vice-president of Gahagan & Bryant Associates was tossing out ballpark figures of what dredging should cost this community. And, unfortunately for would-be entrepreneurs hoping to leverage a "MudCat," a "Dragon," or even the evening's touted device– a 1,200+ horsepower "Wilko"– into hundreds of millions of dollars at the Rivanna Reservoir, such hopes are sinking into the turbid waters of reality.
Four years ago, after two unsolicited proposals landed at the then-leaderless Rivanna Water & Sewer Authority, the Pennsylvania-based firm that was busily rewriting Charlottesville's 2002 post-drought water plan declared dredging too expensive. The firm, Gannett Fleming, had yet to earn infamy for designing a system of eventually fatal overhead concrete panels at Boston's Big Dig. Here, the firm simply claimed that dredging, which doesn't appear to be one of its specialties, would cost up to $225 million, the bulk of the price based on the questionable theory that most of the dredged material would be put in trucks and driven away.
"You could haul it to D.C. for that," Gibson told the audience. "That seems like a high cost."
In contrast to Gannett Fleming's vision of thousands of trucks hauling five million cubic yards of material over 50 years, Gibson suggested that an impending dredge would probably need to move 1.7 to 2.5 million cubic yards, as the reservoir is not yet choked enough to produce so much.
He guessed a total of just $25-30 million and said his firm would like to conduct a full-blown feasibility study to come up with a firmer estimate, and he claims that such estimates are usually five to ten percent from the eventual cost. He said the "tipping fee" paid to any landowner with at least 50 spare acres to clog with mud and sand might bump up the cost a few more million.
"Ultimately, disposal site selection is the cornerstone of any good project," said Gibson. "You need a hole. Whether you find one or construct one, that's what you need."
He and his associate, Rob Kite, said they examined two tracts near the reservoir, including Panorama Farm, a site already known for dirt-farming (as its sells a compost called Panorama Pay-Dirt). Gibson called Panorama a "perfect" site due to its plentiful acreage, its mid-dredging zone location, and its shallow rise above the pool.
(Dredging advocate Rich Collins pointed out that the owners of Panorama haven't expressed an interest or disinterest in such project yet.)
At the meeting, Gibson conceded that dredging would probably require an Army Corps of Engineers "401" permit but tried to assuage attendees– who included Authority director Tom Frederick– over some of the concerns that have erupted in recent days, now that dredging is finally taken seriously. Frederick and his board have thrown their support behind a $143 million plan to upgrade two treatment plants and create a new Interstate highway-hugging, pipeline-dependent reservoir that requires the felling of 180 acres of mature forest.
River-loving attendee Leslie Middleton, who hosts a weekly five-minute WTJU radio program called the Rivanna Rambler, blasted the Hook for providing "partial information" that has fostered "divisiveness." She says she supports both maintenance dredging and the $143 million plan.
"It's an odd, multi-faceted, and– to my understanding– elegant solution to a lot of problems." The plan is said to restore historic stream flows on the Moorman's River by pumping water out of the Rivanna Reservoir during wet times and storing it in the proposed jumbo reservoir.
One thing everyone can agree on is that the 42-year-old Rivanna Reservoir is filling with sediment.
"Today," said Gibson, "we were running aground in a boat that drew eight inches of water, and I couldn't see the bottom. That's turbidity."
In response to an audience question, Gibson said that a full-blown feasibility study by his firm will cost about $275,000, including lake-bottom imaging, geotechnical probing, sediment sampling, and going door-to-door to find a willing disposal site.
One attendee was Mitch King. With Blue Ridge Sand Inc., he offered one of the two unsolicited bids from four years ago. He wants to win the dredging business by employing a system of sluices that simultaneously dewater and classify the material for greater marketability to contractors and landscapers."We need about three acres," said King.
The other unsolicited dredging firm, Dock Doctors, was also in attendance. Owner Don Meyer said he'd planned to buy a farm with the proceeds and create wetlands on the parcel to earn credits for any environmental damage that might occur. He'd offered to perform the dredging for just $21 million.
Dredging supporter Joe Mooney, one of the activists who encouraged Gahagan & Bryant to come to Charlottesville, was asked what he thought of it all.
"I don't know," said Mooney, who slipped into the meeting around 9pm as it was ending, "because I was over at the City Council meeting talking about William Crutchfield's letter."
The founder and CEO of one of the nation's biggest consumer electronics retailers, Crutchfield recently entered the fray with a letter [RTF] blasting the decision-makers. He questioned the expertise of the Nature Conservancy, asked about a potential Gannett Fleming conflict of interest, and worried about the carbon footprint of a system dependent on pumping water uphill. Crutchfield wrote that "prudent businesspeople" would have gotten a second opinion on dredging. And that's what Gibson wants to provide.
"It's not a real complex project," said Gibson. "It's not a real big project. It's middle of the road."