Transboundary Watersheds
Rivers know no borders. They flow freely across landscapes, obeying only the laws of physics. Rivers sustain both human and natural systems. They provide drinking water, serve as a source of irrigation, and supply sediment that sustains soils. They function as conduits for people and goods, their flow generates electrical power, and the force of their floods can reshape landscapes. Rivers are home to many, including aquatic species and human communities living along their banks. Understanding river systems is crucial for supporting and sustaining their critical functions.
Transboundary Rivers
Because some rivers cross political boundaries, including international borders, their governance becomes a matter of cooperation. Several rivers cross the United States-Canadian border in the Pacific Northwest. In recognition of the economic, social, and ecological importance of transboundary rivers, Congress directed the U.S. Geological Survey (USGS) through the 2018 Omnibus Spending Bill to “partner with local Tribes and other Federal agencies as necessary in the area to develop a water quality strategy for transboundary rivers impacted by mining activities." In 2019, the USGS began studying water-quality of selected transboundary rivers in the Pacific Northwest. The goal of this research is to characterize current, baseline water-quality conditions. In addition to contributing to the scientific understanding of these diverse and dynamic natural systems, this knowledge will facilitate future assessments of potential impacts to the river systems.
Regional mining activity might affect water quality and ecological conditions within these transboundary watersheds. Multiple historical, current, and planned large-scale mining ventures could have measurable effects on the water quality and ecological condition of transboundary waters. Establishing an understanding of current watershed conditions will allow scientists to monitor water quality trends through space and time, detect changes, and communicate with stakeholders on both sides of the border about the condition and functioning of these shared, vital resources.
Water Quality Overview
Water quality is one way to understand the health of rivers. Generally, water quality can be thought of as a measure of the suitability of water for a particular use. Scientists study the chemical properties of water because conditions like pH and dissolved oxygen dictate which organisms will thrive. Understanding what is in water can enable predictions of how it will respond in different conditions. This can help managers decide what actions to take or to avoid, promoting the health of the people and ecosystems dependent on rivers.
U.S. Geological Survey scientists perform a range of water quality monitoring tasks in the field and the lab.
The quality of water flowing through a river may be highly variable with space and time. Water quality depends on complex relationships between processes in the watershed. A watershed is all the area of land that drains streams and rainfall to a common outlet such as the ocean, a confluence of rivers, or any point along the stream channel. Physical processes – both human and natural – can influence the quality of water moving through any given watershed. Factors may include the amount, timing, and form of precipitation; terrain; plant and animal communities; and human activities.
A river may have seasonally higher concentrations of sediments corresponding with precipitation increasing the amount of water transported by the river, and thus its power to carry particles. Continuous monitoring of key parameters (measures) such as temperature, pH, and dissolved oxygen allow scientists to understand the critical conditions under which chemical reactions occur. Though the processes are complicated, scientists and land managers have developed standard tools to monitor the health of rivers. Additionally, modelling aided by computers can fine-tune the knowledge for specific rivers and watersheds.
More information about water quality found here: Water Quality | USGS.gov
Access USGS water quality data here: USGS Water-Quality Data for the Nation
Mining
Mines are one form of economic activity that produce materials needed for everyday life. However, mining activities can present a risk to water quality and ecological conditions. Mined material may contain minerals and elements that are released into the environment when material is excavated. Geochemical reactions of mined material with water and air can produce acid mine drainage. Additional elements may be introduced during the processing of mined materials. For example, milling operations historically used mercury to separate gold from other materials. When elements enter water in certain concentrations, they can alter water quality and impact ecological health.
Detecting geochemical changes and determining the cause is complicated by the varied geology within watersheds, the complex nature of these chemical and biological pathways, and the heterogeneity of how water flows through large river systems. Thus, the need for rigorous scientific investigations of these systems, to better quantify risk and protect the health of rivers and all the species that rely upon them.
More about mining and water quality here: Mining and Water Quality
Alaska Watersheds
The Alsek, Unuk, Stikine, Taku, and Salmon Rivers originate in Canada and flow through southeast Alaska before entering the Pacific Ocean. Steep mountain ranges scatter the landscape and glaciers fill valleys and fjords between peaks. Mountain ridges, and, occasionally, even glaciers, define the boundaries between watersheds, dictating which path precipitation takes on its downward journey to the sea. Amidst the rugged topography and harsh climate, the region supports many ecosystems including taiga, mixed forests, scrublands, and grasslands. The United States–Canada border traces northwest along the aptly named Boundary Ranges, forming the coastal region known as the Alaska Panhandle to the west. In Canada, the province of British Columbia is separated along the 60° parallel from the Yukon Territory to the north.
History and Overview
For thousands of years, Indigenous peoples have called this land and its rivers home. An abundance of marine resources, terrestrial mammals, and diverse vegetation sustained their cultures and many of these traditional practices are carried on today. The arrival of European traders in the 1700s initiated an era of natural resource extraction and exportation. The fur trade and mining started first, and timber harvest, commercial fishing, and tourism soon followed.
While the Yukon region spurred the famous Klondike Gold Rush, the southeast transboundary region also attracted droves of prospectors in the late 1800s. In addition to placer gold operations on rivers, mining ventures extracted copper, gold, silver, and lead from bedrock deposits. Over the course of millions of years, land masses (known as "terranes") crashed into the continent, introducing new material, initiating volcanism, and applying enough heat and pressure to metamorphize rocks. These processes concentrated precious metals such as copper, gold, silver, and zinc into geologic deposits that occur primarily in a region in British Columbia known colloquially as the “Golden Triangle.”
The recently completed Northwest Transmission Line has brought power to the southern transboundary region and accelerated mineral exploration and mine developments, especially in the Golden Triangle. Planned large-scale mining could produce more than three gigatons of tailings — more than has been mined in the past 100 years at Bingham Canyon, the largest mine in the United States. Large-scale mining could have measurable effects on the water quality and ecological condition of transboundary rivers.
Research Activities
The U.S. Geological Survey is assessing the baseline conditions of transboundary watersheds in the southeast Alaska region in partnership with tribal nations and government agencies. Collecting data on water quality and watershed conditions can help identify natural sources of water quality constituents such as metals. These data will contribute to a comprehensive understanding of current conditions which will serve as a reference (baseline). This information can then be used to monitor the long-term water quality during the operation of large-scale mines in the Canadian portion of the watersheds.
The USGS operates streamgages on the Alsek , Salmon , Stikine , Taku , and Unuk Rivers. These gages record the quantity of water flowing in the rivers (discharge), which can be viewed on NWIS . In addition to stream flow measurements, the USGS is characterizing water quality, sediment quality, biological condition, regional geology and mineralization potential.
U.S. Geological Survey Scientists engaged in various research activities and maintenance in Alaskan watersheds during the brief time when stations are safely accessible.
The immense volume of water carried in large Alaskan transboundary rivers necessitates careful planning for scientists to collect representative samples. The USGS uses rigorous methods to ensure that the water and sediment samples that they collect are reflective of conditions throughout the river. Field visits are scheduled every six to eight weeks to capture seasonal variations.
The health of the ecosystem is a major motivation for this scientific work. Stakeholders want to ensure that salmon runs continue to thrive due to their ecological, cultural, spiritual, and economic significance in the region. Additionally, it is important that ecosystems function as a resilient web of systems, especially when facing global pressures such as climate change.
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Alsek Watershed
The Alsek watershed is a 28,922-square-kilometer basin located in the northern portion of the Alaska panhandle region. The main stem of the Alsek River travels south from Canada collecting meltwater from the numerous glaciers perched in the Ruby Ranges, St. Elias and Fairweather Mountains, and Alsek Ranges.
The Tatshenshini River flows from the northeast to join the Alsek shortly before the United States-Canadian border. Indigenous peoples recognize the Alsek watershed as part of their traditional territories, including multiple Tlingit Kwáans and the Champagne and Aishihik First Nation.
The Yukon Territory village of Haines Junction is in the north of the watershed, at the junction of the Haines and Alaska Highways. The Alsek watershed spans parts of Glacier Bay National Park and Preserve in Alaska, Tatshenshini-Alsek Provincial Park in British Columbia, and Kluane National Park and Reserve in the Yukon Territory. Nearly the entirety of the Alsek watershed is protected as parks and there are no large-scale historical, current, or proposed mining operations in the watershed. A large open-pit copper mine proposed in the early 1990s in the Alsek watershed did not result in development.
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Taku Watershed
The Taku River drains an 18,517-square-kilometer watershed and is formed by the confluence of the Inklin River and Nakina River. The Nakina River flows southwest from the Northern Gulf Forelands of British Columbia, passing through the Yukon-Stikine Highlands before joining the Inklin River which flows northwest through the Boundary Range. The Tulsequah River is another major tributary of the Taku River, entering the mainstem near the international border.
Three conservancies and one provincial park form a network of protected areas in Canada, and the Tongass National Forest protects the entirety of the Alaskan portion of the watershed. The conservancies are managed to ensure that the lands and waters forming the traditional territory of the Taku River Tlingit Nation continue to support their way of life. Juneau, the state capitol of Alaska, is located near the mouth of the Taku. Four historical large-scale mining operations in the Taku watershed persist as sites of mineral exploration and prospecting, as well as environmental remediation. Gold, silver, copper, lead, and zinc constitute the major commodities extracted.
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Stikine Watershed
The Stikine River drains a 50,893-square-kilometer watershed. The Stikine River arises in the Stikine Plateau of British Columbia and flows through the Boundary Ranges where it is joined near the international border by the Iskut River, a major tributary that drains southwest from the Skeena Mountains.
The Stikine watershed is asserted as the traditional territory of the Tahltan people, as well as the Tlingit Shtax’héen Kwáan in the Iskut watershed, and the Liard First Nation, Ross River Dena Council, and Kaska Dena Council in the eastern uplands. The small Alaskan portion of the watershed is protected as part of Tongass National Forest, part of which is managed as the Stikine-LeConte Wilderness. Twenty-four conserved areas in Canada range in size with the largest, Spatsizi Plateau Wilderness Provincial Park, located in the eastern headwaters of the watershed. Mount Edziza Provincial Park and the Todagin Wildlife Management Area cover much of the center of the watershed, while the Stikine River Park protects the upper river corridor.
The region remains sparsely developed; Dease Lake and Telegraph Creek are small communities in British Columbia connected to the Stewart-Cassiar Highway. Gold rushes brought miners to the basin in the 1860s and precious metal mining continues today. One large-scale mine currently operates in the watershed, while three projects are in the exploration and permitting phases of development. Mining ventures in the watershed target gold, copper, and silver ores. A proposed hydroelectric project on More Creek, a tributary which drains to the Stikine via the Iskut, is currently undergoing environmental review.
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Unuk Watershed
The Unuk River drains 2,476 square kilometers, from the Boundary Ranges in Canada to the Behm Canal, Alaska. Mountain ridges separate the watershed from the Iskut River—a tributary of the Stikine—to the north, and the Salmon River to the south.
The Tahltan and Tlingit Sanyaa Kwáan recognize the Unuk watershed as part of their traditional territories, and they remain stewards of the land. Misty Fjords National Monument Wilderness, administered as part of Tongass National Forest, encompasses the Alaskan portion of the watershed. In Canada, Lava Forks and Border Lake Provincial Parks protect areas immediately adjacent to the border.
Mineral deposits in the upper region of the watershed are associated with the Stikinia geologic terrane. In addition to extensive placer mining for gold, hard-rock mining has focused on large porphyry gold, silver, copper, and molybdenum deposits. Within the Unuk watershed, there are four large-scale mines that are currently operating or in the later stages of permitting and development.
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Salmon Watershed
The Salmon River drains meltwater from the Salmon Glacier in British Columbia and crosses the international border near Hyder, Alaska, before terminating in the Portland Canal. At 526 square kilometers, the salmon watershed is comparatively small, and its topography is primarily mountainous.
The watershed is part of the traditional territory of the Tlingit Sanyaa Kwaan. In Alaska, the state manages small parcels of land, including the community of Hyder, while the majority of the area is part of Tongass National Forest. A highway connects Hyder with the larger municipality of Stewart, British Columbia, which is just a mile away, onto major Canadian transportation routes.
Gold, silver, and copper mining occurred episodically on several properties in the area, including at the Premier underground mine which opened in 1918 and at the time of its closure in 1952 was the largest gold mine in North America. Efforts are currently underway to refurbish operations and develop new mines at these sites.
Just reaching the rivers can be a challenge. Scientists travel by float plane, helicopter, and boat to access remote field sites. Steep valleys, long periods of cloudy weather, and wintry conditions add another level of complexity.
Once USGS scientists arrive at the sites, they work to capture a wealth of data, including physical properties and concentrations of major ions, metals, suspended sediment, and nutrients. Several water quality parameters, such as temperature and pH, are measured directly in the river. Other parameters, such as the concentrations of metals, must be obtained from a lab. Scientists traverse the rivers collecting bottles filled with water from multiple locations and depths in the channel. Laboratory scientists use precise techniques to analyze additional parameters that cannot be measured in the field. In some cases, they have developed new cutting-edge techniques to detect constituents from low volumes of collected material. Data from these discrete field visits are publicly available through NWIS .
Once a year in the late summer or early fall, USGS biologists make a special visit to the southeast Alaska transboundary rivers to collect baseline biological data. They gather samples of organisms at different levels on the food web, including moss from rocks on streambanks, and juvenile fish endemic to the local stream sampled. Laboratory scientists run tests to measure the concentrations of constituents, including metals, in different tissues. These data may inform researchers and managers about the health of the individual organism and species. The data may also clarify how different organisms uptake metal from the aquatic environment and metals move through the food web.
Few recent geologic maps exist for southeast Alaska, meaning that little is known about the underlying geologic conditions in the Alaskan portion of transboundary watersheds. Improving our understanding of the bedrock geology is a major first step for characterizing transboundary watersheds. For instance, the bedrock geology can help evaluate the potential acid generating or neutralizing effects of rocks in the watersheds. Additionally, geologic mapping may inform the location and abundance of precious metal deposits. These deposits are prevalent on the Canadian side of the watersheds and are presumed to extend into the United States. Understanding the regional geology and possible distribution, types, and abundance of both mined and unmined deposits in Alaska and Canada is crucial to determination of baseline conditions and predicting the possible downstream effects of future mining. The USGS seeks to close this knowledge gap by synthesizing information available from existing geologic maps and geochemical databases, as well as collecting and analyzing geochemical samples of stream sediment, and conducting a geospatial analysis of mineralization potential within the watersheds.
Washington Watersheds
Washington state and British Columbia share an approximately 350-mile long border along the 49th degree of latitude. The headwaters of many Washington Rivers, including the mighty Columbia River, are located in the Canadian Rockies. Some, like the Similkameen, have headwater streams in Washington which flow into Canada before returning to the United States. While cooperation and monitoring efforts by US, Canada, Tribal, First Nations, state and province governments occurs to some degree along the entire border, the USGS Transboundary group actively studies two basins, the Skagit and the Similkameen.
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Skagit Watershed
The Skagit River originates in the North Cascade Range and drains into the northern end of the Puget Sound. Fed by over one hundred glaciers, the river traverses high mountainous terrain in Canada and the United States before forming a sweeping valley near its mouth. Much of the upper portions of the watershed are protected by Manning and Skagit Valley Provincial Parks in British Columbia, and North Cascades National Park, Ross Lake National Recreation Area, and Okanogan and Mt. Baker- Snoqualmie National Forests in Washington. Seattle City Light owns and operates three dams as part of the Skagit River Hydroelectric Project which supply approximately 20 percent of the city’s power. The uppermost, Ross Dam in Washington state, impounds the 23-mile-long Ross Lake which extends into British Columbia. The areas above Ross Dam are considered part of the transboundary Upper Skagit watershed.
The USGS is conducting a baseline assessment and monitoring to determine whether proposed upstream mining activities in British Columbia are having or will have measurable effects on the Skagit River water quality. The data characterizes current conditions and allows for detection of changes in long-term water quality. Scientists are tracking both trace elements and precious metal concentrations in water, sediments, and aquatic organisms.
Working with Canadian partners, the USGS has installed continuous water quality monitoring instruments near the international border and at a downstream gage. The sensors measure dissolved oxygen, pH, conductivity, turbidity, temperature, and fluorescent dissolved organic matter. Discrete water quality sampling supplements the continuous record by providing further data throughout the year on nutrients, major ions, metals, and suspended sediment. During field visits, scientists collect samples of stream-bed material to analyze sediments. They also collect aquatic organisms to determine metal concentrations in tissues at multiple levels in the food web.
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Similkameen Watershed
The 72-mile long Similkameen River originates in the North Cascade Range of British Columbia and Washington state. It shares a drainage divide with the Upper Skagit watershed, which drains the North Cascades to the west while the Similkameen drains to the east. After passing through British Columbia and entering Washington, the Similkameen joins the Okanogan River, which flows into the Columbia River in north-central Washington. Water from the Similkameen River is used for irrigation, drinking, livestock watering, recreation, and industrial use, and also sustains life. The Similkameen watershed falls within the purview of the International Lake Osoyoos Board of Control, an International Joint Commission (IJC) board which cooperatively manages outflows from Osoyoos Lake. Manning and Cathedral Provincial Parks in British Columbia and North Cascades National Park protect portions of the watershed.
The Similkameen watershed has been mined since the 1850s. Prospectors initially targeted placer gold around Oroville and Nighthawk, and later developed hard rock mining operations in the region. Mine shafts and tailing piles remain visible across the landscape. In British Columbia, a large open-pit mining operation continues to produce copper, gold, and silver.
Previous monitoring in the watershed has found elevated concentrations of several metals, at times in excess of water quality guidelines for aquatic health. High levels of arsenic have been linked to historical tailings in the mining area between Hedley, British Columbia and the United States border, prompting a listing under Section 303(d) of the federal Clean Water Act in 2000 and 2001. Water and sediment quality remain a concern as the legacies of historical mining unfold, and modern large-scale mines operate and expand in the Similkameen watershed.
The USGS is characterizing current trace element and precious metal concentrations in water, sediment, and tissue at the United States-Canada border. The monitoring complements previous efforts by multiple Federal, State, Provincial, Tribal and First Nations entities, allowing for the detection of changes in long-term water quality. Data generated will contribute to an understanding of how historical, current, and proposed upstream mining activities in British Columbia affect water and sediment quality on the Similkameen River.
The USGS has equipped the Nighthawk streamgage with continuous water quality monitoring instruments. The sensors measure dissolved oxygen, pH, conductivity, turbidity, temperature, and fluorescent dissolved organic matter. Discrete water quality sampling supplements the continuous record by providing further data throughout the year on nutrients, major ions, metals, and suspended sediment. During field visits, scientists collect samples of stream-bed material to analyze sediments. They also collect aquatic organisms to determine metal concentrations in tissues at multiple levels in the food web.
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Enloe Dam
Enloe Dam forms a 1.6-mile-long impoundment on the Similkameen River in Okanogan County, Washington. The 100-year-old structure has not produced hydropower since 1958 and is being considered for removal. However, the volume of sediments trapped behind the dam and the concentrations of sediment contaminants from historical mining and smelting could pose a risk to downstream water and sediment quality, necessitating special handling. In a related study, the USGS is providing information on the concentrations of trace elements such as arsenic and mercury and precious metals such as gold and silver in bed sediments stored behind Enloe Dam. Water and sediment quality data collected upstream near the international border will be incorporated into the evaluation of Enloe Dam.
Kootenai Watershed (Idaho-Montana)
The Kootenai River (Kootenay when in Canada) originates from the Northern Rocky Mountains in southwestern British Columbia. It arcs south through Montana and Idaho before turning north back into British Columbia where it joins the Columbia River just beyond Lake Kootenay.
The Kootenai River and its tributaries are home to a diversity of aquatic organisms including culturally important, threatened, and endangered species such as white sturgeon (Acipenser transmontanus) and bull trout (Salvelinus confluentus). The sedimentary rocks forming the Northern Rockies contain rich coal deposits that have been mined for many decades.
The coal beds and associated rock layers are enriched with other minerals as well, and in the last two decades, elevated concentrations of selenium in downstream waters have raised concerns. Selenium is nutritionally essential in minuscule amounts, but in excess, it is an environmental contaminant known to bioaccumulate and cause reproductive effects in fish and wildlife. The USGS is conducting studies to better understand selenium in the Kootenai transboundary watershed.
History and Overview
The Kootenai River originates in the Northern Rocky Mountains physiographic region, in southwestern British Columbia. The river is impounded along with the Elk and Bull Rivers by Libby Dam forming the transboundary reservoir Lake Koocanusa. The Columbia River Treaty between the United States and Canada led to the construction of Libby Dam in 1972 as part of a cooperative effort to manage the water resources of the Columbia River watershed. The reservoir has a volume of 7.16 cubic kilometers and provides flood storage, hydroelectric power production, and recreation benefits. The 148-km reservoir straddles the United States-Canadian border and impounds water from about 23,271 square kilometers, or 47 percent, of the Kootenai River watershed.
Downstream of Libby Dam, the Kootenai River flows through northwestern Montana and northeastern Idaho before crossing the international border back into British Columbia, where it joins the Columbia River. The transboundary Kootenai watershed contains critical habitat for the threatened bull trout and genetically pure west slope cutthroat. The river basin also serves a vital role in maintaining adequate flows and water quality for several endangered salmon and steelhead runs in the Columbia River. The Kootenai River below the reservoir provides critical habitat for the white sturgeon (Oncorhynchus clarkii lewisid), which was listed as endangered in this river during 1994 through the U.S. Endangered Species Act.
The Montana Department of Environmental Quality has identified Lake Koocanusa as threatened by selenium and listed the water body under Section 303 (d) of the US Clean Water Act . Six water treatment plants designed to remove selenium are currently operating in the Elk River watershed, with additional treatment plants planned for the future. The U.S. State Department and the Department of Interior are actively engaged in this high visibility transboundary issue.
USGS Science in the Kootenai Watershed
The USGS is contributing scientific expertise to help stakeholders in the Kootenai watershed answer several questions. This body of research is guided by the following questions:
- What are the current water quality conditions in the Kootenai watershed?
- What is the nature and extent of selenium pollution in the watershed?
- How does selenium travel and behave throughout freshwater food webs?
- What are the most appropriate monitoring techniques to clarify selenium risk to aquatic communities, and to provide stakeholders with actionable data and information?
Water Quality Monitoring
Water quality platforms provide real-time data at various depths on Lake Koocanusa in northwestern Montana.
Water quality data are collected by the USGS and several other agencies in the Kootenai watershed. These data are available through NWIS and form the basis for watershed-scale assessments of selenium and other water quality trends. Scientists continue to collect water quality information at a network of stream gages and non-gaged locations throughout the watershed. These measurements will inform and refine selenium and nutrient loading determinations. Water quality is not uniform throughout the water column, especially in stratified water bodies like Lake Koocanusa, where density differentials inhibit mixing. To obtain water quality data at multiple depths, specially equipped platforms are positioned in Lake Koocanusa. They provide near-real time data, which can be viewed through the National Water Quality Information System .
Biotic Monitoring
The USGS works with partners to collect biological samples from aquatic organisms throughout the Kootenai watershed. A 2018 study showed that selenium concentrations in fish from the Kootenai River were elevated relative to fish in other rivers, with some fish exceeding relevant water quality criteria. A 2018–2019 study generated further baseline data on selenium and mercury concentrations in fish tissue of the Kootenai River and principal tributaries in Montana and Idaho. Current efforts seek to replicate past fish tissue sampling, establish further reference sites, and conduct spring-season sampling. Scientists are experimenting with novel methods for collecting and analyzing biological samples. For instance, algae represent a large trophic step in the concentration of selenium in the food web. However, collecting algae samples from rivers is not a simple task becasue algae grows in thin films on rocks. Scientists at the Idaho Water Science Center have developed three methods for collecting algae samples from rivers. This type of analysis not only generates robust data for understanding selenium movement in the Kootenai system, but it also contributes more broadly to establishing scientific best-practices. Another area of active research is comparison of selenium and other constituent concentrations between different tissues in the same fish species. Each tissue has the potential to accumulate selenium in different concentrations, with implications for fish health. Because there are limited tissues on these tiny fish, USGS laboratory scientists are developing new methods for doing low-mass, high precision analysis of samples.
Food Web Research
In order to comprehensively evaluate the ecological risks of selenium in aquatic environments, it is necessary to understand bioaccumulation and trophic transfer. USGS biologists are engaged in several projects examining selenium concentrations in organisms to better understand selenium pathways through aquatic food webs. Research indicates that the dietary route of exposure generally dominates bioaccumulation processes. This is important because the traditional ways of predicting bioaccumulation and toxicity in aquatic animals on the basis of exposure to water concentrations do not work for selenium, necessitating new research. The USGS has published data and reports in support of ecosystem-scale selenium modeling. This effort aims to provide an ecosystem-scale model that illustrates the site-specific range of potential selenium exposure and bioaccumulation that can inform the basis for regulatory decision-making. The biodynamic model requires information not only on dissolved selenium, but on other ecosystem compartments as well including particulate material, invertebrates, fish, and wildlife. The modeling approach brings together the main concerns involved in selenium toxicity: likelihood of high exposure, inherent species sensitivity, and close connectivity of ecosystem characteristics and behavioral ecology of predators. This approach leaves room for model refinement as more data become available and understanding of the system improves.
Idaho-Montana Project Links
Kootenai Watershed Partners and Cooperators
Kootenai Watershed NWIS Data links
- USGS gage 12301933 (Kootenai River below Libby Dam)
- USGS gage 12305000 (Kootenai River at Leonia)
- USGS gage 12310100 (Kootenai River at Tribal Hatchery)
- USGS gage 12322000 (Kootenai River at Porthill)
- USGS gage 12302055 (Fisher River near Libby MT)
- USGS gage 12304500 (Yaak River near Troy MT)
- USGS site ID 12307750 (Moyie River near mouth)
