Land and Water Resource Change

The Issue: Most of the Lower Duwamish River Valley in Seattle, Washington, is less than 20 feet above sea level; consequently, the river valley is prone to flooding during high tides, extreme rainfall, and high streamflow. In addition, groundwater inundation—localized coastal flooding due to a rise of the groundwater table with global sea-level rise—may compound flooding issues in the area. The...

The Issue: Sediment loads in the Puyallup River and its major tributaries, the White River and Carbon River, are high and river channels are dynamic. While there is a relatively rich history of sediment transport and channel change studies in the Puyallup River and its tributaries, there has not been an integrated assessment of channel-elevation trends in nearly a decade. This lack of up-to-date...

The Issue: The Chehalis River deposits sediment in Grays Harbor, which the U.S. Army Corps of Engineers regularly dredges to maintain shipping access. The sources and overall volumes of sediment transport in the lower river were last assessed in the 1960s. Given substantial changes in land-use and watershed regulations over the subsequent half-century, there is an open question as to if or how...

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: 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: 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...

The Issue: Ongoing channel aggradation has reduced flow conveyance along the lower White River, increasing the flood risk in urban-suburban areas. A refined understanding of the delivery, transport and deposition of sediment in the White River, and how those processes may be influenced by climate and existing dam operations, is necessary in order to plan for future flood hazard in the lower White...

Fine-grained sediments in the lower reach of the Sauk River are adversely affecting the health and spawning of Chinook salmon. Climate change and forestry practices have been proposed as suspected causes of a reported increase in sediment loading to the river. To determine the amount and timing of suspended-sediment loading to the river and possible connections to adverse effects on Chinook salmon...

Glaciers, snow, and ice sheets are important components of the Earth's water and climate. They respond to and indicate changes in climate, as well as exerting an influence on global and regional climate. They also have an effect on water resources, serving as natural reservoirs. Measuring changes in the size and volume of glaciers and snowpacks provides one direct way of knowing what kind of...

RRAWFLOW: Rainfall-Response Aquifer and Watershed Flow Model

The Issue: The State of Washington issues Municipal Stormwater Permits to local governments in the Puget Sound region that require them to develop and implement a stormwater management program that reduces the discharge of pollutants and protects the quality of water in rivers, streams, lakes and Puget Sound. The permitees in partnership with the State need to measure whether water quality and...

The Issue: Seasonally frozen ground occurs over approximately one-third of the contiguous United States, and the extent and duration of frozen ground have been decreasing as a result of global warming. In semi-arid regions such as the Columbia Plateau and Snake River Plain in the Pacific Northwest, nearly all natural recharge occurs between October and March when intermittent or seasonal frozen...