Aquatic Ecosystems and Habitats

The Issue: Polycyclic aromatic hydrocarbons (PAHs) are a class of oil-derived compounds widely distributed in fresh and marine waters. They pose a significant toxicity risk to fish. It can be challenging to pinpoint the source of PAHs found in wild fish populations. PAHs are widespread and come from many sources, so it is hard to determine whether fish exposure is event-related or consistent with...

The Issue: Mercury contamination and toxicity threaten Pacific lamprey recovery in the Columbia River basin. Methylmercury concentrations in larval Pacific lamprey from tributaries in the mid-Columbia were measured to be as high as 4.0 µg/g wet weight. At these concentration levels, injury is predicted to occur in more than 50% of larval and adult fish and more than 90% of early-life stage fish...

The Issue: Native American treaty rights depend on the availability of adequate and high-quality streamflow across the Western Washington, which can be degraded by water and land use, reservoir operations, and climate change among other factors. Streamflow during critical low-flow periods depend on groundwater discharge from aquifers, which also is vulnerable to human activities in the Western...

The Issue: Wildfires can negatively impact reservoirs and water supply. On August 4th, 2021, a lightning strike started the Muckamuck fire in Okanagan County, Washington. The fire burned approximately 13,297 acres (~21 square miles) of forest and shrubland before it was contained. The burn engulfed a large portion of the area which drains into the Conconully Reservoir, a popular location for...

The Issue: Streamflow permanence refers to the probability that a stream will lose surface flow (become a dry channel), as well as the timing, duration, and frequency of drying. Patterns of streamflow permanence drive important decisions regarding forest management and other land uses. The Colville National Forest Land and Resource Management Plan (2019), for example, specifies riparian management...

The Issue: The Quillayute River supports habitat for migrating, spawning, and rearing steelhead and salmon. All six miles of the river are influenced by tides, which influence its stage, discharge, and exchange with groundwater. The Quillayute River, like many salmonid-bearing rivers in the Pacific Northwest, is projected to warm in the coming decades due to projected increases in atmospheric...

The Issue: Puget Sound watershed nutrient loads are known to have an impact on marine water quality along with wastewater treatment plants discharging to Puget Sound. To effectively reduce and control nutrient loads to the Sound, the Washington State Department of Ecology needs a regional watershed model that fits within their Puget Sound Nutrient Source Reduction Project’s management framework...

The issue: National interests in water information are important but challenging to incorporate into planning and operation of a monitoring network driven by local information needs. These interests include an understanding of the spatial variability in water availability across the United States, anthro-physical factors including climate and land use that affect water availability, and federal...

The issue: Learning more about where and how much nitrates there are in the Nooksack river basin. How USGS will help: Provide continuous nitrate concentration data at three locations. Provide validation water samples analyzing for nitrate concentration. Compute nitrate load estimates using stream discharge data coupled with newly collected nitrate concentration data.

The Issue: The Enloe Dam, a 100-yr old structure on the Similkameen River in Washington State, has not produced hydropower since 1958 and options are being considered for potential removal of the dam. The concentrations of sediment contaminants (primarily trace elements from a long history of mining and smelting operations in the US and Canada) trapped by Enloe Dam are unknown and may be high...

The Skykomish and Snoqualmie River basins in western Washington provide spawning, rearing, and migration habitat for several salmonid species, including Endangered Species Act-listed Chinook salmon, steelhead trout, and bull trout. The production, abundance, distribution, and the health of fish and other aquatic life is strongly influenced by water temperature, which affects their physiology and...

The Issue: In Washington State, groundwater (GW) inflow to streams, or baseflow, is essential for maintaining aquatic habitats, and for out-of-stream uses such as irrigated agriculture during the typically dry summers. However, the National Hydrologic Model (NHM) currently is most suited to predicting total daily streamflow. This project aims to assess the NHM’s performance in simulating baseflow...