Flush a toilet in Butte, and the water is treated before it ends up in Silver Bow Creek. But raindrops and melted snowflakes trickle in untreated -- and all that water picks up sediment, heavy metals and mine waste along the way.
During a big rainstorm like the one Butte experienced Aug. 21, storm water rushes down the Butte Hill and through the town’s gulches in true gully-washer fashion, sending everything from cigarette butts and motor oil to litter and toxic mine waste directly into the creek.
Butte-Silver Bow and the Environmental Protection Agency have spent millions trying to turn the tide -- more than $50 million in the past 27 years.
The EPA on Thursday met with reporters to talk about three new projects expected to wrap up next month. Besides improving the health of Silver Bow Creek, the work will spiff up areas along some of the city's busiest thoroughfares and may even create space for a new park.
As the work continues, these and other projects are teaching scientists and city officials new lessons about water and the pollution it carries.
“This is an iterative process studying how storm water comes off the Hill, where it goes and what it’s carrying, said Julie DalSoglio, director of the Montana EPA office.
Preventing storm water runoff from contaminating Silver Bow Creek is required by the state. Each municipality in Montana is required by the Department of Environmental Quality to conform to a Small Municipal Separate Storm Sewer System, or MS4, permit.
“Storm water pollution is an issue regardless of where you have civilization,” said Matt Vincent, chief executive of Butte-Silver Bow. “I think there’s a real good storm water plan in place. There have been monumental improvements over the years. I can remember in the 1990s there was so much sediment and runoff. All those hillsides in Butte were barren mine waste. We didn’t have any sediment basins or storm water ditches."
Not long ago, water runoff was carrying so many heavy metals residents would pan for gold in the drainages coming off Butte Hill.
Today, says Vincent, the gold-seekers are gone. "We have decreased our impacts on urban watershed and Silver Bow Creek by orders of magnitude."
The EPA and the county have put in a multitude of storm water controls, including drop inlets, catchment basins, hydrodynamic devices, curbs and gutters, required storm water management during construction permits, ditches and channels.
But a problem that plagues all cities, Butte included, is non-point source pollution -- the oil that leaks from cars, the dirt people sweep off their sidewalks into the storm drains, leaves, trash and a multitude of other human-created detritus. Whatever goes into the storm drains is destined for the creek, untreated. Storm water does not pass through any treatment plants in Butte.
“We’re trying to educate; that’s the biggest piece,” Vincent said. “Whatever we can do to educate people that they can take actions to improve Silver Bow Creek.”