LOLO – Where does Lolo Creek go?
Once that was a question for Lewis and Clark to explore. Now it’s more a puzzle for residents along U.S. Highway 12 to ponder as the landmark waterway consistently disappears in late summer. On Wednesday, about 50 people came to the Voyage of Discovery’s old campsite, Traveler’s Rest, to learn about a new exploration of Lolo Creek’s hidden qualities.
“The creek has been drying up in many years when it hadn’t before,” said Bobbie Bartlette of the Lolo Watershed Group, which organized the gathering. “We’d like to understand the reason for that, and what we can do about it. Is it climate change, water usage, growth in the community?”
The volunteer organization put together a request to Montana Bureau of Mines and Geology to research the water question. Of the 11 proposals submitted, Lolo’s ranked No. 1. That’s brought a long table full of scientists to town to begin several years of research on the creek’s behavior.
“We need to find the places where something interesting is going on, and try to figure that out,” explained Camela Carstarphen of the Butte-based Bureau of Mines and Geology. Despite its name, the bureau spends much of its time studying the state’s landscape to learn how farmers, ranchers, communities and the natural environment use the state’s groundwater.
Carstarphen said initial studies show the creek near its headwaters pushes about 18 cubic feet of water per second downstream. After it’s picked up most of its tributary streamflows, Lolo Creek hits 35 cfs. By the time it reaches Traveler’s Rest, that’s shrunk to 1.5 cfs, and this year, disappears altogether before it reaches the Bitterroot River. Bureau work teams are drilling several new test wells in strategic places to get a better picture of how both the surface and groundwater move through the drainage.
That helped attract the Department of Natural Resources and Conservation to do a pilot study of its own. DNRC is charged with developing a statewide surface water study, and Lolo work will be the training ground over the next five years.
“We’re trying to capture a low-flow year – looks like we kind of got it this year – a medium-flow and a high-flow year,” said DNRC’s Aaron Fiaschetti. “We put in a lot of gauges this summer. We’ll start the study this October.”
That study will produce a water budget – a picture of where Lolo Creek’s water comes from, when it comes, and where it gets used. The work feeds into the Bureau of Mines and Geology groundwater investigation, which has the job of explaining “why” those whats, whens and wheres take place.
And those studies depend on research done by a couple of programs based at the University of Montana, including the state climate office and the geosciences department. State Climatologist Kelsey Jensco will gather decades of past precipitation and temperature data and future forecasts to reveal what water supplies come in from above. Hydrogeologist Payton Gardner will tease out the chemical fingerprints of isotopes and cosmic ray traces that reveal where the rain and snow joined the underground aquifer, how long it’s been down there and how fast it moves from place to place.
Meanwhile, the private Clark Fork Coalition has been teaming with the U.S. Forest Service in rehabilitating old logging roads around the headwaters of Lolo Creek. That work erased 13 miles of road this summer, and restored seven miles of mountain streams that were formerly too sediment-clogged for fish to use.
Once the pile of information gets big enough, the studies might point to ways irrigators could be more efficient in their farming needs. It could help Lolo residents decide where and when they might need a fourth water well to serve their community. It could produce drought management plans similar to a system pioneered by the Blackfoot Challenge that keeps farms and ranches functioning in the Blackfoot River drainage.
“We don’t know what the results are going to be,” Lolo Watershed Group member Michele Landquist said. “But we hope to add some tools to our toolbox.”