The lowdown on sewer

Where does all the gray water go?


Alone under a stand of tamaracks, 50 yards from a tent, small shovel in hand, a backpacker having taken care of business doesn’t question how Mother Nature will manage what is buried. But throw together a few thousand people living more or less permanently in the Rattlesnake Valley, and the volume of human waste overwhelms the Mother. People—finite wisdom, flawed technology—must step in.

In 1910, Missoulians piped raw sewage out of the city and into the Clark Fork River. In 1963, the city erected a wastewater treatment plant between the toilets and the river. In 1998, Missoula, Butte/Silverbow, Deerlodge, Smurfit-Stone, the Department of Environmental Quality and the EPA signed an agreement to reduce nutrients in the Clark Fork River. Part of Missoula’s agreement was to connect unsewered properties to the city system.

Last year, it was the Rattlesnake’s turn to hook up, according to a Missoula Valley Water Quality District study of pollution trouble spots. Most of the Rattlesnake’s 570 septic units presently in use within city limits are seepage pits. The problem, according to the city, is that seepage pits drain gray water—including nitrates, bacteria and viruses—directly into the ground, eventually contaminating the aquifer. Water from the pits dirties Rattlesnake Creek, too, and in turn, the Clark Fork.

One year ago, the conflict about how to best manage the Rattlesnake’s waste erupted into a lawsuit. Loreen Folsom charged the city with suppressing the public’s input. In December, Judge Douglas Harkin ruled in her favor. Since then, the public has inundated Council with information—comments, data, PowerPoint slides and overhead transparencies. Though a handful are begging for city sewer, most either don’t believe their septic systems are the main culprits in polluting the river, or they don’t trust that the city’s treatment plant is a better vehicle with which to manage waste. Alternative onsite systems, some contend, would do a better job of keeping the river and aquifer clean, are less expensive and would also help ensure that neighborhoods don’t further expand at homeowner expense and developer profit.

Next week, the public’s time to comment will likely be over. The proposed special improvement district (SID), the fate of the Rattlesnakers—and downstream water quality—will be in the hands of the Council. One community member has made them a request. In part because citizen distrust of the city is still thick, the Council, he believes, should appoint an impartial, independent committee to look at the problem and various solutions. “The city right now has very little credibility,” says Michael Bennett, a former Council member who has lived up the Rattlesnake for 20 years. A recommendation from an independent body might be more palatable to citizens suspicious that the city is not listening to them, or considering viable alternatives to sewer.

Here are some of the options: the older, no-frills tanks and pits used in many Rattlesnake homes currently; alternative onsite septic systems; and, via city sewer hook-up, the wastewater treatment plant.

Since 1970, Hunton Pre-Cast Concrete has poured concrete into molds in Missoula. Dave Hunton sells the barebones component of a septic system—the basic cement tank—and he explains exactly how it works: Waste flows into the septic tank. The heavy solids sink to the bottom, and scum—grease and fat—floats to the top. The clear liquid in the middle, the gray water, runs through a filter and into a dry well, from which it seeps into the soil and rock. Newer systems, Hunton says, feature added components to additionally filter the gray water.

The city itself has researched newer systems, which city officials admit are promising. Though some systems effectively remove between 40 and 96 percent of total nitrogen, the city considers such alternatives short-term, costly solutions that work best in larger yards.

The Waterloo Biofilter is one such alternative. Various states and the EPA have tested it extensively. “The main key,” says Iggy Ip, with Waterloo Biofilter Systems Inc., a Canadian company, “is it’s a very simple system.” From the septic tank, where microbes convert ammonia into nitrates, gray water flows through the Biofilter. The filter, Ip explains, is a tank filled with patented foam cubes where bacteria grow. Gray water, sprayed across the top of the tank, trickles down through the cubes, where bacteria further break down the waste. Nitrogen, a gas, is released into the air. Before seeping into the ground, half the water is routed back through the Biofilter. The Biofilter, says Ip, removes anywhere between 50 to 70 percent of total nitrogen.

The U.S. Environmental Protection Agency website recommends the Waterloo Biofilter as an effective alternative to traditional waste management. The tank comes in large and small sizes, can be installed above-ground, and, according to the EPA, requires only minimal maintenance. In Canada, some homes pipe the filtered gray water back into the house for laundry or baths. Golf courses reuse the water for irrigation. The system costs $10,000 to $15,000 Canadian, says Ip—roughly $7,000 to $11,000 American dollars.

For each of the 477 Rattlesnake properties in the proposed special improvement district, the total cost of hooking up to the city sewer would be approximately $9,000—but financed over a 20-year period, say sewer opponents, the project would cost residents upwards of $20,000.

If the city’s main concern is clean water and some of the new systems have proven to be effective, why not let people choose their own onsite system? “It isn’t a long-term solution for the community,” says Bruce Bender, director of Public Works. Monitoring the systems and being accountable for their maintenance, says Bender, is critical. Plus, he says, even the newer systems rely on the city. Septic tanks eventually need the solids pumped out. Trucks deliver that waste to the city’s plant.

Meanwhile, the wastewater treatment plant is upgrading services and capacity. By July, the plant is expected to be able to remove about 78 percent of total nitrogen and 87 percent of phosphorous, and its capacity will expand by one third.

If Rattlesnakers learned from their peers that connecting to the sewer was their best option, they might be convinced. But so far, Bennett’s proposal for a committee that includes citizens has not been met with action. Sooner rather than later, Council is likely to take the decision, and all the waste that has accompanied it, out of their hands.

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