July 9, 2001
Duvall moratorium may be eased with limitations
City Council to take public comments
by Lisa Allen
Valley View Editor
DUVALL - The city's building application moratorium, in place since July of 1999, may be lifted on a limited basis after the sewage treatment plant outfall extension project is completed next month, officials say. The extension of the outfall, which now ends at the riverbank, will improve mixing of the effluent that goes into the Snoqualmie River.
According to City Engineer Elizabeth Goode, the work had to be completed during the time the state Department of Fish and Wildlife calls the "fish window," which falls between June 16 and August 15. Fish populations are affected the least during that time frame. The $330,000 job is being performed by Fury Construction.
The new outfall will extend 60 feet into the deepest part of the river. Currently, the city is in violation of the Department of Ecology's (DOE) standards of heavy metal discharge into the river.
Goode said metals include copper, silver and zinc. Some metals occur naturally, but the copper probably comes from pipes, she said. Better mixing of the effluent will lessen the effects of the metals on fish.
"Based on the outfall extension being installed we will request the DOE amend our National Pollution Discharge Elimination System (NPDES) permit," she said. "We are asking them to revise the permit so we would no longer be in violation."
Goode said if the permit was revised, the plant would have some extra capacity.
"We think we may have some limited additional capacity," she said. "The City Council will take testimony on that at their regular 7 p.m. City Council meetings on July 12 and 26. The purpose is to listen to how folks think the additional capacity should be allocated. We also don't know what DOE will be willing to grant. And, there will continue to be a sewage capacity problem until we do a major plant expansion."
Completion of the planned expansion will be at least five years down the road, she said. Property needed for the plant expansion has been acquired, but she explained that the city is looking at different technologies, options and costs.
"We don't want to increase rates beyond what people can pay," she said. "We want to produce quality effluent, but the problem is cost."
Goode said the plant was originally designed for 6,000 residents, and with the buildout of all the new developments that have been approved, population will soon go from 4,500 to an estimated 6,600. The Copper Hill mixed-use development alone, under construction across from the sewage treatment plant, will add 88 new dwelling units, plus businesses.
"That's why we went under the moratorium," she said. "The outfall will take care of the metals, but we still have a total hydrology problem."
Goode said early on in the life of the plant, officials thought that because Duvall was a rural area, the plant could handle up to 9,000 residents. But that thinking changed when the town became more suburbanized, with more appliances in each residence.
Experts studying the differences between the rural and suburban household concluded that the element in the newer homes that makes the difference is the garbage disposal, said Goode.
"Homeowners using garbage disposals don't realize that all that stuff has to be digested in the plant," she said. "Plus, it takes a lot more water to wash it all down. All that adds to the stress on the plant, so it can't handle as many households. Residents put as much as a grocery bag full of stuff down the drain in a week that could be composted or go in the garbage. Maybe it would help if people were aware of that."