Watershed Impacts

The diversity of the land and the water has made the region abundant in its natural resources. Since European colonization, the area has seen significant impacts of our use and extraction of these natural resources. Understanding how these activities have and continue to impact the ecosystem of the watershed allows us to mitigate current damages and and prevent future environmental degradation.


Though there are no dams within the Salmo watershed itself, downstream dams have greatly altered the ecology of the watershed. The Salmo River, once named the “Salmon” river, lost its salmon runs (and its “n”) as a result of hydroelectric dam construction downstream on the Columbia River. Historically, the watershed was home to abundant salmon populations. First Nations would travel from across the land to harvest these fish. Salmon were also a part of the diet of many wildlife in the area. After spawning, these fish die and provide a significant amount of nutrients into river, creeks, and riparian areas, which eventually helps support entire ecosystems. Other fish such as bull and rainbow trout were also impacted by dam construction closer to the Salmo, such as those on the Pond d’Oreille River, and have been severely reduced in their numbers since construction.

On top of being a physical barrier dams significantly alter the hydrology of rivers, changing how much and when water flows, and can flood areas while reducing flow in others. Lifecycles of a variety of wildlife rely on the natural of flow of these rivers, and changes in these flows then drastically impact their ability to survive.

Invasive Species

As invasive species are becoming and increasing problem worldwide, the watershed is not immune to their effects. For example, since the construction of the dam downstream of the Salmo on the Pend d’Oreille reservoir, the majority of the fish population is comprised of non-native species.

Native species often provide fundamental ecosystem functions for their surrounding environment. Wildlife and other species living in the same environment also have adapted to the presence of these species, and can even be a resource for some. Invasive species are a threat to the natural function of an ecosystem, as natural function and resources are lost when invasive species out-compete native ones.

Mining and Forestry

Though mining is no longer a prevalent industry in the watershed, their impacts can still be seen. Abandoned mine sites and tailings ponds are scattered across the landscape. The locations of these tailings ponds include remote areas as well as adjacent to developed areas and well-used bodies of water. These tailings ponds have since been documented and there is continual work for remediation of prioritized sites.

Forestry continues to be an active industry around the Salmo watershed. Historically, the Salmo area was covered in large western red cedars and extensive old growth forests. Mining and forestry has played a large role in the removal of forests, wetlands, and riparian areas. These resulted in a significant loss in habitats and changed the hydrology and biology of the watershed.


The water and the landscape makes the Salmo watershed great for recreational activities such as hiking, fishing, and whitewater sports like kayaking and rafting. These can be enjoyed with minimal impact on the environment; however, there are often unintentional impacts. One main concern of recreational use is disturbing wildlife, which can be damaging to the individuals and to the offspring. For example, Harlequin ducks are a blue-listed species that inhabit fast flowing channels of the Salmo River. However, they are easily scared off and can abandon their offspring if they are disturbed. Trampling off trails and on vegetation can degrade habitat and resources for wildlife. Increasing recreational use is a concern for the wildlife of the watershed. Responsible and educated recreation is an important to ensure that the Salmo watershed can remain enjoyable for current and future generations.

Road Development

With development and industry, roads need to be built for access. In addition to removal of natural vegetation, roads also have a significant impact on hydrology of nearby creeks and rivers. Road construction often require channelizing streams, which removes natural twists and bends of flowing channels. With this loss, streams flow faster and can erode riverbanks at a faster rate. This increase of speed also takes away nutrients from the surrounding areas next to the stream, reduces habitats for fish and aquatic birds, and in some cases become a barrier for fish migration. Roads next to streams without a buffer zone of vegetation can increase sedimentation, choking channels, and lose important spawning habitat for fish. Other changes in hydrology can occur when streams and groundwater are diverted for road construction, which again can have significant impacts on the flow of water and spawning habitat.