ScholarWorks at University of Montana

The Montana Legacy Project aims to conserve important forestland most recently owned by Plum Creek Timber Company in northwestern Montana. In 2008 the Legacy Project partners, The Nature Conservancy and The Trust for Public Land, reached an agreement with Plum Creek to purchase approximately 310,000 acres of timberland. The transaction is structured as a three-phased purchase to take place over the next two years. The first closing occurred in December 2008 and the second took place in February of 2009. The acquisition portion of the project is to be completed in December 2010. While the Legacy Project partners will hold a portion of the land temporarily, ultimately all land will be conveyed into a mix of federal, state and private ownership. Much of the land included in this purchase is within the Clark Fork River watershed, including land in the upper Clearwater Valley near Seeley Lake, the Lolo Creek watershed, the Mill Creek area, Fish Creek and Petty Creek west of Missoula, the Rock Creek area and in the Garnet Mountains between Potomac and Interstate 90. It is part of what is known as the Crown of the Continent, one of the largest, most intact ecosystems remaining in the United States. The landscape provides habitat and habitat linkages for several threatened and endangered species including grizzly bears, lynx, and bull trout. Much of the land is low elevation terrain that is critical for terrestrial and aquatic species and highly susceptible to development pressures. The Legacy Project partners will raise funds from federal, state and private sources to implement this project.

Random sampling of particle composition of instream substrate can help quantify the effects of fire on watersheds. Using the Wolman pebble count, hydrologists of the Bitterroot National Forest monitored five East Fork Bitterroot River sites over eight years and documented substrate particle composition. In each site a minimum of 100 samples were taken, intermediate axes were measured and particle sizes were determined. Percentiles were calculated in the Forest Service database in order to determine statistical accuracy of the data. Observations indicated little change in composition in the sampled watersheds during the study period.

Bioaccumulation studies of a resident aquatic organism can provide a direct indicator of bioavailable metal in mine-impacted rivers. This approach is supported by concurrently evaluating bed sediment metal concentrations and water quality data. We examine the effectiveness of mine waste remediation in the Clark Fork River using a resident biomonitor (Hydropsyche spp., O: Trichoptera) and streambed sediment. Over a 19-year period, Cu concentrations declined in both indicators at the two most upstream stations, a pattern coincident with remediation events. Sediment Cu declined at most stations along the 200 km study reach. However, Cu concentrations in Hydropsyche in the middle (85 km) and lower (190 km) reaches were significantly influenced by total annual discharge, masking the impact of remediation on bioaccumulation, at least to date.

A biodynamic model was used to make predictive assessments of Cu bioaccumulation under varying metal exposures. We experimentally-derived physiological constants and used site-specific geochemical field conditions to predict Cu bioaccumulation in Hydropsyche (Hydropsyche is a useful proxy for metal exposure in sensitive species). Hydropsyche has a fast Cu uptake and loss rate. However, dietary Cu influx is ~3-fold higher than dissolved influx, suggesting that Cu uptake from food prevails in nature for that species. Bioaccumulation data from the Clark Fork was used to validate this model. The model under-predicted Cu concentrations in Hydropsyche by ~70% when only dissolved Cu concentrations are considered. However, predicted concentrations fall within range of observed values when dietary influx is incorporated into the model. Ongoing field monitoring coupled with biodynamic modeling is a unique approach that strengthens our predictive capabilities as metal exposure conditions change.

This topic was presented as both a talk and as a poster.

Flood Insurance Rate Maps (FIRMs) commonly referred to as flood maps are primarily used for two purposes:

1. Information for local communities including counties, municipalities and tribes to enforce local regulations pertaining to development in “100-year floodplains” and “floodways”
2. For management and regulation of mandatory flood insurance rules.

To a large extent the first purpose complements efforts related to river protection. FIRMs are developed from the best scientific and hydrologic information available. In 2005 a national effort was initiated by FEMA to convert paper FIRMs into a modern digital format, referred to as DFIRMs. When feasible, DFIRMs incorporate new hydrologic and hydraulic analysis and floodplain mapping study information.

The proposed poster will show areas of the Clark Fork that have been remapped are in the process of being re-mapped. The preliminary DFIRM map for Missoula County was released on April 6, 2009, however this draft is being updated and a new revised version will be released in the future. This Geographic Information Systems (GIS) formatted map reflects current mapping and mapping of some new hydrologic and hydraulic analysis study work. The Montana Department of Natural Resources and Conservation (DNRC) utilized a grant from FEMA to contract PBS&J to perform both the digitization and new floodplain mapping work for this project. This GIS project was undertaken in cooperation with local governments. Data from the new DFIRM is not used for insurance purposes until the map is finalized.

The Groundwater Information Center database (GWIC) has records of 85,400 wells in the Clark Fork Basin, most (73,200) have a reported use of “domestic”, that is, they are wells that serve individual households. Other wells provide water for irrigation, municipal, industrial/commercial, and stockwater use. Although the number of wells seems large, groundwater accounts for only 7 percent of the water withdrawals in the basin. Surface water dominates the water withdrawals; an estimated 1,510 million gallons per day (MGD) of surface water is withdrawn (93 percent), primarily for irrigation use, as compared to 112 MGD of groundwater. Of the groundwater withdrawn, most is used for irrigation, municipal water, and industrial uses. Domestic use accounts for only 8 percent of groundwater withdrawals.

In the Clark Fork Basin, there are generally two types of aquifers: (1) shallow water table and (2) deeper confined to semi-confined. The extent of basin-fill aquifers generally coincides with the extent of basin-fill deposits. Near-surface sand and gravel deposits (mostly Quaternary alluvium) coincident with the floodplains of main-stem streams contain very permeable alluvial water-table aquifers that store and yield large volumes of water. These aquifers are generally in hydraulic connection with adjacent streams. The deeper confined-semi-confined aquifers occur in layers of sand and gravel separated by silt and clay.

Pumping groundwater will remove water from aquifer storage. Long-term water-level data, collected as part of the Montana Groundwater Assessment Program, show changes in groundwater storage in the basin-fill aquifers across the Clark Fork Basin. The data show that groundwater fluctuations in basin-fill aquifers vary with regard to the timing and magnitude of recharge and discharge. Most long-term trends are stable, indicating little or no depletion of basin-fill aquifer storage. Water levels in parts of the highly utilized deep aquifer in the Flathead Valley show long-term declines.

In groundwater systems, water removed by pumping is derived from aquifer storage, and some combination of increased recharge and/or decreased groundwater discharge (as base flow to streams). During the months of December, January, and February the steady low flows shown in stream hydrographs represent the “base flow” period, when groundwater contributes most, if not all stream flow. Annual December-February flows were averaged to provide a measure of the base-flow rate at stations on the Clark Fork, Bitterroot, Swan, and Blackfoot Rivers. The base-flow graphs show variability from year to year but flat long-term trends.

Fish populations in the Upper Clark Fork River were completely decimated in the early 1900s due to the deposition of hazardous mining waste. Improvements in wastewater treatment and mine waste remediation have allowed fish population to return to the river, although in numbers less than 10% of expected carrying capacity. In April 2009, 100 trout were surgically implanted with radio transmitters throughout the Upper Clark Fork River, from Warms Springs to Turah. Transmitters were spatially distributed evenly throughout the study area and species were selected based on relative abundance found in the river: 72 brown trout Salmo trutta, 15 westslope cutthroat Oncorhynchus clarki lewisi, 6 rainbow trout O. mykiss, 6 suspected cutthroat/rainbow hybrids, and 1 bull trout Salvelinus confluentus. An additional 100 trout will be surgically implanted with radio transmitters in the spring of 2010. Radio tagged fish are relocated at least once a week during spring, summer, and fall (more during periods of spawning) and at least twice per month during the winter. Fish will be tracked year round until winter 2011. Using the relocation data, we will identify areas of critical habitat, such as spawning areas, refuge habitat, and over-wintering habitat. Movement patterns will also be analyzed to assess how fish are reacting to the environmental factors unique to the Upper Clark Fork River Basin (pulsed metal events, increased temperature, and others). By identifying the critical habitat of the system, efforts can be made to guide remediation in order to be most effective for fisheries restoration.

The Blackfoot River Watershed has benefited from a long history of cooperative partnerships involving federal, state, and county agencies, local conservation organizations, landowners, and other stakeholders committed to solving problems and reaching common goals. The successful restoration of key fisheries and their associated riparian areas within the watershed is one such goal.

In order to improve water quality and enhance bull trout and west slope cutthroat trout fisheries in Blackfoot tributaries, the Big Blackfoot Chapter of Trout Unlimited has partnered with area landowners, the Natural Resources Conservation Service, the Blackfoot Challenge, and the U.S. Fish and Wildlife Service , among others, to fund and implement several area stream restoration projects.

This assessment summarizes eight revegetation projects implemented in the Blackfoot River Watershed between 2005 and 2008. We gather background information for each project, identifying species lists, seed sources, container sizes, plant material suppliers, and soil and hydrological site conditions by project. We report on revegetation methods and techniques employed on each project, and summarize ongoing project maintenance programs. During the 2009 field season we tabulated revegetation species survival, established project photo points, evaluated the various revegetation techniques and surveyed the general site conditions and responses following project implementation.

This comprehensive document takes an in depth look at these restoration efforts, specifically focusing on success rates of the revegetation component of each project. Finally, with this evaluation we can make effective recommendations that will help guide partners involved in future restoration efforts within the Blackfoot River watershed and beyond its boundaries.

A remediation goal in Silver Bow Creek is to restore trout populations which provide recreational angling opportunity and are an indication of ecosystem recovery. Remediation has been in progress since 1998. All of the mainstem fish populations were lost as the creek received more than a century of copper mine tailings. Several tributary fish populations survived, including genetically unaltered westslope cutthroat trout Oncorhynchus clarki lewisi in German Gulch. In 2009, we tagged 977 fish (259 westslope cutthroat trout, 664 brook trout Salvelinus fontinalis, 54 longnose sucker Catostomus catostomus) with Passive Integrated Transponder (PIT) tags in three tributaries to Silver Bow Creek; German Gulch, Brown’s Gulch, and Blacktail Creek. Stationary antennas at tributary confluences continuously monitored the timing and direction of fish movements between Aug-7 and Nov-15, 2009. In German Gulch 7.4% (n=256) of tagged westslope cutthroat trout and 8.0% (n=158) of tagged brook trout moved into Silver Bow Creek. 23.1% (n=169) of the brook trout tagged in Brown’s Gulch moved into Silver Bow Creek. Once they moved into the mainstem, nearly all fish remained in Silver Bow Creek throughout the study. In Blacktail Creek, only 1.1% (n=350) of the fish tagged were detected in Silver Bow Creek. Of 54 longnose sucker tagged, none moved into Silver Bow. German Gulch and Brown’s Gulch trout populations may provide an important population subsidy to Silver Bow Creek’s nascent trout population. Blacktail Creek’s relatively large population of brook trout may be functionally disconnected from Silver Bow Creek, and may not provide the same benefit to upper Silver Bow Creek.

In Montana and other parts of the arid west, water diversion can create environmental challenges for downstream fish populations. Diverting water out of a stream in the autumn and winter has particular implications for autumn-spawing fish whose eggs are in the gravel all winter, such as brown trout and bull trout. This study was designed to examine how the year-round diversion of water by a local mining industry affects redd building and egg-tofry survival of wild brown trout in a Montana creek. To measure redd-building activity, I had access to fifteen years of annual redd-count data at this site. To measure egg-to-fry survival, I counted fertilized brown trout eggs into meshlined baskets and placed these baskets into artificial redds. I removed these baskets after hatch in April and tallied the number of live fry, dead fry, live eggs and dead eggs. While the eggs were developing in the gravel, I measured parameters critical to egg development and survival that could be affected by dewatering, including: intergravel dissolved oxygen (IGDO), intergravel temperature, stream temperature, rate of flow through the gravel, and depth and water velocity at each artificial redd. There was no autumn or winter dewatering during the course of this study, so I cannot comment on the effects of a dewatering. The survival rate for the first two years was similar, 38% and 35%. Survival was considerably lower the third year, measuring only 8.5%. This may be due to a longer, colder winter the third year. The data collected and methods developed in this study will be useful for a future study in the event of an autumn or winter dewatering.

When you wade into the Clark Fork River in the summer you will most likely slip on the rocks because of benthic diatoms and the mucilaginous excretions they use to adhere to the substrate. Diatoms are microscopic, jewellike, single-celled algae with silica cell walls. They possess characteristics of both plants and animals, such as photosynthesis and directed motility. Diatoms are the base of the aquatic food chain, but they can also be harmful, producing powerful neurotoxins that contaminate crustaceans, bivalves and fish in the oceans and also the massive stalk growths of Rock Snot (Didymosphenia geminata) that choke out other aquatic life in some rivers and streams. Diatoms are good indicators of water quality and have been used to monitor the health of the watersheds of Montana since the 1970s. As an example, assessments were made of diatoms in the Clark Fork River upstream and downstream of the Frenchtown pulp mill in 2005, 2007 and 2009. These assessments suggest that there is some impairment of beneficial uses due to excess nutrients, and this assessment did not change over the sampling period. Examples are presented of diatoms common to the middle Clark Fork and considered indicative of various water quality conditions.

Since its inception in 2005, the CFWEP has reached over 13,000 students and 250 teachers in western Montana with an science inquiry-rich curriculum using the Upper Clark Fork River as an outdoor laboratory and professional scientists and university faculty as instructors. The programs mission is to foster environmental stewardship and scientific decision making through place-based learning. This poster will present an overview of three of the CFWEPs main programs: the Clark Fork Education Portal, an on-line educational resource; the CFWEP Base-level program and the Milltown Dam Education Program. Overview will include student and teacher data, as well as field data collected at various sampling sites on the Upper Clark Fork from Butte to Missoula.