Rob Roberts understands why people flock to Rattlesnake Creek. As a resident of the Rattlesnake Valley and an avid fly-fisherman, he appreciates the recreational opportunities the creek provides. And so when he wades through Greenough Park, tearing down man-made rock dams and draining people’s favorite soaking pools, he’s not trying to be a spoiler; he’s doing it for the health of the creek.
“I have no problem knocking those down,” says Roberts, western field coordinator for Trout Unlimited, though he is undertaking his troubleshooting hike as a personal project. “Bull trout just moved up the creek in late July. If the water level continues to drop and those fish try to come back down, they could get stuck until the fall rains come.”
Anecdotal evidence suggests that recreational rock dam construction on the creek has increased sharply in recent years, and their existence is causing a number of undesirable consequences: waders are destroying vegetation and creating trails to the pools; diverted water is causing migration of the stream channel and increased erosion; and large pools contribute to the warming of the creek water and reduction of its flow.
According to Ladd Knotek, fisheries biologist for Montana Fish, Wildlife & Parks, the issue has passed the point of being a nuisance and is becoming a serious problem for the bull and brown trout fishery.
“If they are just moving a few rocks around it’s probably not that big of a problem, but there are people building dams that are 2 or 3 feet high” Knotek says.
He knocks them down whenever he sees them, but by the next hot afternoon persistent soakers are usually busy rebuilding them, Knotek says.
“People need to realize that it’s not legal and that it creates real problems for bull trout.”
Roberts also makes it a habit of breaching dams whenever he finds them.
On Saturday, Aug. 12 he went out looking for them.
“I think some people think [Rattlesnake Creek] is pristine, and some think it’s screwed up,” Roberts says. “I want to see for myself what condition the creek is in.”
So Roberts, along with two colleagues, began a voluntary accounting of the stream’s health. Their goal is to walk the entire length of the creek from the mouth to the Rattlesnake Recreation Area trailhead, a distance of about six miles. They covered about a third of that distance Saturday, knocking down illegal dams, picking up trash and documenting obstructions, pumps, diversions and eroded stream banks along the way.
“I think we’ve decided that the Pabst pounder seems to be the favorite beer of people hanging out along the banks of Rattlesnake Creek,” Roberts said afterward.
But he found signs of human use more troubling than litter.
“We found no less than 14 rock dams that spanned the entire creek,” he said, noting that the trio didn’t even bother dismantling the smaller off-channel dams.
The Missoula Conservation District (MCD) is charged with administering the Montana Natural Streambed and Land Preservation Act (commonly referred to as the “310 law” after the permit that’s required to do any work in or around Montana streambeds). At their July 14 meeting, MCD reviewed a complaint from landowners concerned about dams in the creek behind their house.
Arlene and Harold Braun have lived on Sycamore Street along the banks of the Rattlesnake for 26 years. The Brauns say in the past they enjoyed watching children play in the creek’s small pools, but in recent years the dam building has gotten out of hand.
“This year, particularly, the dams have gotten very ambitious and the pools a lot bigger,” Harold Braun says.
Braun—like Roberts and Knotek—is increasingly concerned about the effects the dams are having on fish spawning, water temperatures and erosion.
But the Brauns have another concern:
“As those dams get more ambitious they force the flow in new directions and the water is undercutting the bank on the west side of the creek,” says Braun.
The Brauns say if the dam-building keeps up, water will likely undercut a big cottonwood on their property, which could topple in spring runoff.
A violation of the state’s 310 law is a misdemeanor offense punishable by a fine of up to $500. But at MCD’s recent meeting, Knotek acknowledged the difficulty of punishing dam builders.
“What are we going to do if we catch a bunch of kids playing in the river? Haul them into juvenile court?” Knoteck asked the board.
MCD District Administrator Tara Comfort and Knoteck suggested, and board agreed, that the best way to reduce dam-building is to educate people on the negative impact such casual construction exerts on the resource.
“I don’t think threatening people and warning them that it’s illegal is the right approach,” Comfort said at the meeting. “We don’t want to be the big bad government trying to take away their fun. We need to explain to them that what they are doing is a detriment to the resource.”
The MCD board agreed to start developing an educational outreach campaign, which might include programs at the Rattlesnake School as well as flyers for Rattlesnake residents. Knotek is also considering putting up signs near the worst spots, though he notes that with summer winding down, new dam construction is likely to become less of a problem.
Roberts says he hopes increased awareness of the issue will lead to residents keeping a closer eye on the overall health of Rattlesnake Creek.
“My motivation for doing this doesn’t just involve rock dams,” he says. “I’m looking more long-term. How can we create a larger movement to repair some of the more serious disturbances?”
In the meantime, the MCD board is eager to see the results of Roberts’ step-by-step accounting, which he plans to complete before the end of the month.
“There are a lot of people in the Rattlesnake who really care about the health of the creek up there,” Comfort says. “I think some of the people building these dams are those same people.”