Welcome to the cfwep.org Frequently Asked Questions (FAQ) page. Here you can find answers to commonly asked questions about the Clark Fork Basin, environmental science, and the Clark Fork Watershed Education Program (CFWEP).

Q: What is the Clark Fork Basin?
A: The Clark Fork Basin includes most of western and northwestern Montana. Water in this area drains to the Clark Fork River, a major headwaters stream of the Columbia River. The headwaters of the Clark Fork River begin in the Upper Clark Fork Basin near Butte and Anaconda, an area that was heavily environmentally impacted by over a century of industrial mining. From there, the Clark Fork River flows approximately northwest through the Deer Lodge Valley. At Garrison, Montana, the Little Blackfoot River joins the Clark Fork. At Drummond, Montana, the Flint Creek joins the river. At Rock Creek, Montana, Rock Creek joins the river. At Milltown, Montana, just east of Missoula, the Blackfoot River joins the Clark Fork. As it continues to flow west, the Clark Fork picks up the Flathead and St. Regis Rivers. Eventually, the Clark Fork flows into Idaho and Lake Pond Oreille. This lake drains into the Pond Oreille River, which flows to the Columbia.

Q: What is a watershed?
A: A watershed is any area that drains water to a common point (such as the Clark Fork River). A watershed can be thought of as a large funnel that collects rainfall, snowmelt, and surface and groundwater flows. Watersheds can be small- any small creek is part of a small watershed- and very large- the Clark Fork, a large watershed itself, is only a segment of the Columbia River watershed, which itself is only a segment of the Pacific Ocean watershed. Watersheds are bounded by divides, or high points in the topography that separate watersheds. In North America, the most well-known drainage divide is the Continental Divide. Rain falling on the west side of the Continental Divide flows to the Pacific Ocean, while rain falling on the east side flows to the Gulf of Mexico or the Atlantic Ocean. Watersheds are important to everyone, because we all live in a watershed, and because watersheds control water flows.

Q: What is being done to restore the Clark Fork Basin?
A: The Clark Fork River and surrounding ecosystems were heavily damaged by over 100 years of industrial mining and smelting in Butte and Anaconda. In the early days of mining, waste rock and tailings were regularly discharged into Silver Bow Creek, the Clark Fork River headwaters. The composition of the waste led to acidic waters with high concentrations of heavy metals and other toxins. Most aquatic life in the Upper Clark Fork could not survive these impacts, which also posed a risk to human health, and made groundwater beneath Butte, Anaconda and Milltown toxic. For the past several decades, the Basin is being restored. Mine wastes are being removed from Silver Bow Creek, and the stream has been rebuilt and revegetated. The Milltown Dam and mine waste backed up in its reservoir have been removed. Mine dumps on the Butte Hill have been capped and revegetated, and are regularly monitored to ensure that waste does not spread and again pose risks for human and aquatic life. All around the Basin, restoration projects are ongoing to return the Clark Fork Watershed ecosystems to healthy conditions. When all is said and done, over one billion dollars (most from BP-Arco, the owner of most of the historic Butte and Anaconda mine workings) will have been spent to restore the Basin.

Q: What is being done to manage the Berkeley Pit?
A: The Berkeley Pit, an open pit copper mine started in 1955 and abandoned in the early 1980's, has been filling with water. The water is toxic due to extremely high concentrations of metals from the pit and the connected underground mine workings. Water levels continue to rise. The Horseshoe Bend Water Treatment Plant was constructed adjacent to the pit in order to eventually treat the contaminated water, preventing the water of the pit from infiltrating surrounding ground and surface water. For more information, visit the PitWatch website at www.pitwatch.org.

Q: How does mine waste impact streams, groundwater, and animal and human health?
A: Due to the composition of the Butte ore body, significant acid mine drainage occurred in the Upper Clark Fork. Butte ore is high in fool's gold, or iron pyrite, a compound of iron and sulfur. When exposed to water and air, pyrite oxidizes, leading to rust (iron) and sulfuric acid. As the sulfuric acid mixes with surface water, streams and groundwater, the acidity also causes the metals present in Butte ore (copper, lead, cadmium, zinc, to name a few) to dissolve in the water in high concentrations. The resulting acidic water, with high concentrations of toxic heavy metals, poses extreme risks for fish and other aquatic life, vegetation, and humans. The mobile nature of water can cause the contimation to spread, as in the case of the Clark Fork River, where contamination spread 120 miles downstream from the sources in Butte and Anaconda to the Milltown Dam near Missoula.

Q: Why was the Milltown Dam removed?
A: A historic flood in 1908 washed considerable mine tailings from Butte and Anaconda down the Clark Fork River. Some wastes settled out in the broad floodplain of the Deer Lodge Valley. A large volume of waste continued down the River to the Milltown Dam near Missoula. Backed up against the dam, the toxic sediments settled out in the Milltown Reservoir. In the early 1980's, arsenic, a carcinogen that can be quite toxic to humans, was found in the groundwater that supplied Milltown and Bonner residents with drinking water. The source of the arsenic contamination was eventually traced to the historic mine wastes in the Milltown Reservoir. As a result, the dam was removed, and wastes are being removed from the reservoir and isolated from the Clark Fork River. The removal of the dam also removed a barrier to fish passage, which is particularly beneficial to native bull trout.

Q: Are there fish in Silver Bow Creek?
A: Yes. Historically, Butte mine wastes rendered the creek devoid of aquatic life. Since restoration work began, trout have been found returning to the creek, and there have long been suckers and other bottom-feeding species present. There are still issues preventing the creek from reaching its maximum potential as a fishery. Treated sewage from Butte is discharged into the creek, and the increased nitrate levels result in an overabundance of aquatic vegetation that can lead to very low dissolved oxygen levels. The five mile stretch of the creek downstream from the sewage discharge is still inhospitable to some aquatic life, trout included. A future planned upgrade of the treatment plant should remedy this problem. Additionally, there is some data indicating that water runoff from the Butte hill is introducing metals and acidity to the creek, though to a much smaller degree than in the past. A planned upgrade of the Butte stormwater system should help to alleviate this issue.

Q: How did the Clark Fork Watershed Education Program (CFWEP) begin?
A: The Natural Resource Damages Program (NRDP) of the State of Montana initially funded the Clark Fork Watershed Education Program (CFWEP) in 2005. With the amount of time, effort and resources going into the restoration of the Clark Fork, the NRDP felt that an investment in education about the restoration was essential to the future health and sustainability of the Clark Fork Basin. Since that time, CFWEP has expanded to serve more teachers, more students, and the public.

Q: What services does the Clark Fork Watershed Education Program (CFWEP) provide?
A: The CFWEP works with students, teachers, universities, non-profit groups, government agencies, and the general public. CFWEP's core curriculum involves middle school students in a week of in-class lessons and activities about watershed and environmental science, restoration, and environmental assessment, capped off by a day-long field trip to two field sites, one more impacted, one less impacted. CFWEP also provides Upper Clark Fork tours and field trips for students of all ages, and connects middle and high school students interested in field science with mentors and research projects. CFWEP offers a variety of other science- and place-based lessons and activities upon request for K-12 teachers. Furthermore, CFWEP provides various professional development opportunities for teachers. As part of its services for the public, CFWEP offers presentations regarding environmental science and the Clark Fork for community groups, conferences, and public events; hosts events to connect the public with restoration and science; and collaborates with other community education groups, Clark Fork organizations, and state agencies to inform the public about the Clark Fork environment and the ongoing restoration. To request a CFWEP service, or with questions about the Clark Fork, restoration, or environmental science, Contact Us.