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Hydrologic Hazards

The WAWSC works with many partners to monitor, assess, and conduct targeted research on a range of hydrologic hazards so that policymakers and the public have the understanding they need to enhance preparedness, response, and resilience. Real-time flood information in combination with flood inundation mapping is used by emergency management agencies to provide forecasts and warnings to mitigate near-term flood risk. The probabilistic analysis of historic flood information is used to mitigate longer-term risk by FEMA though their flood insurance program, and by planners and engineers through the proper design of bridges, culverts, levees, and stormwater facilities. Real-time water supply information is used by water-resource managers to formally declare drought in Washington State, while post-declaration monitoring and assessment provides an understanding of the effects of drought response activities on short- and long-term water availability. Acute sedimentation information is used by river management agencies to plan for and mitigate changes in flood-conveyance and increased flood risk.

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Filter Total Items: 10
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Analysis of USGS Surface Water Monitoring Networks

Analysis of USGS Surface Water Monitoring Networks

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...
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Washington Water Science Center
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Analysis of USGS Surface Water Monitoring Networks

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...
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Pilchuck Dam, July 10, 2020

Channel change monitoring following the Pilchuck Dam removal

The issue: In the summer of 2020, the Pilchuck Dam will be removed, allowing salmon access to the upper third of the Pilchuck River watershed for the first time in over a century. This removal will be associated with a short period increased sediment delivery, as the river re-works material trapped behind the dam. While the volume of impounded sediment is small and major changes in the downstream...
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Washington Water Science Center
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Channel change monitoring following the Pilchuck Dam removal

The issue: In the summer of 2020, the Pilchuck Dam will be removed, allowing salmon access to the upper third of the Pilchuck River watershed for the first time in over a century. This removal will be associated with a short period increased sediment delivery, as the river re-works material trapped behind the dam. While the volume of impounded sediment is small and major changes in the downstream...
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SR530 OSO Landslide Sediment Transport

SR 530 Slide

In the immediate aftermath of the SR530 Landslide, the USGS supported first responders and decision-makers as a key member of the collaborative effort to monitor the stability of the landslide deposit and the associated impoundment of the North Fork Stillaguamish River during rescue operations. With the initial disaster response now over, longer-term questions have arisen regarding the stability...
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Washington Water Science Center
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SR 530 Slide

In the immediate aftermath of the SR530 Landslide, the USGS supported first responders and decision-makers as a key member of the collaborative effort to monitor the stability of the landslide deposit and the associated impoundment of the North Fork Stillaguamish River during rescue operations. With the initial disaster response now over, longer-term questions have arisen regarding the stability...
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Raging River Project Location

Raging River Temperature

The Issue: Large, in-channel wood that helps to create and maintain healthy aquatic habitat in rivers throughout the Pacific Northwest was removed from many rivers in the past. In 2009, King County put wood back into the river to restore the Raging River watershed. To guide the county's restoration of the Raging River watershed, managers need to know the effect of restoration actions on in-stream...
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Washington Water Science Center
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Raging River Temperature

The Issue: Large, in-channel wood that helps to create and maintain healthy aquatic habitat in rivers throughout the Pacific Northwest was removed from many rivers in the past. In 2009, King County put wood back into the river to restore the Raging River watershed. To guide the county's restoration of the Raging River watershed, managers need to know the effect of restoration actions on in-stream...
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Pasco Groundwater Storage

Pasco Groundwater Storage

The Issue: Since 1952 water diverted from the Columbia River has been used to irrigate parts of the Pasco basin in eastern Washington. As a result of the surface-water irrigation, groundwater levels generally have risen in the area. The increases in groundwater fluxes and groundwater in storage have created a need to better understand the flow system before and after the start of irrigation to...
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Washington Water Science Center
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Pasco Groundwater Storage

The Issue: Since 1952 water diverted from the Columbia River has been used to irrigate parts of the Pasco basin in eastern Washington. As a result of the surface-water irrigation, groundwater levels generally have risen in the area. The increases in groundwater fluxes and groundwater in storage have created a need to better understand the flow system before and after the start of irrigation to...
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FEMA High Water Marks Report Cover

FEMA High Water Marks - Western Washington Flood, January 2009

The Issue: Significant flooding occurred throughout western Washington on January 7 and 8, 2009. As part of its Hazard Mitigation effort, the Federal Emergency Management Agency (FEMA) Region X needs documentation on the extent of flooding for verifying Preliminary Digital Flood Insurance Rate Maps (DFIRMs) and corresponding Flood Insurance Studies (FIS) that have been recently completed, or are...
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Washington Water Science Center
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FEMA High Water Marks - Western Washington Flood, January 2009

The Issue: Significant flooding occurred throughout western Washington on January 7 and 8, 2009. As part of its Hazard Mitigation effort, the Federal Emergency Management Agency (FEMA) Region X needs documentation on the extent of flooding for verifying Preliminary Digital Flood Insurance Rate Maps (DFIRMs) and corresponding Flood Insurance Studies (FIS) that have been recently completed, or are...
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FEMA Technical Support

FEMA Technical Support

9722-DRE00 - FEMA Technical Support, Pre-Declaration, January 2009 Floods - Completed FY2009 A wide plume of warm moist air streaming in from west of Hawaii caused widespread rainfall throughout western Washington in early January 2009. National Weather Service flood stages were exceeded in many different basins, most of which drain from the west side of the Cascade Range. Flows at four long-term...
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Washington Water Science Center
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FEMA Technical Support

9722-DRE00 - FEMA Technical Support, Pre-Declaration, January 2009 Floods - Completed FY2009 A wide plume of warm moist air streaming in from west of Hawaii caused widespread rainfall throughout western Washington in early January 2009. National Weather Service flood stages were exceeded in many different basins, most of which drain from the west side of the Cascade Range. Flows at four long-term...
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Mount Rainier

Puget Hazards

Nationally, the USGS monitors and assesses geologic and hydrologic natural hazards. In the Puget Sound Basin, common hazards that also can cause damage include earthquakes and floods. Other hazards in the region that cause less damage or happen less frequently include landslides, debris flows, tsunamis, and volcanic eruptions. Although much is known about these natural hazards, mitigation and...
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Washington Water Science Center
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Puget Hazards

Nationally, the USGS monitors and assesses geologic and hydrologic natural hazards. In the Puget Sound Basin, common hazards that also can cause damage include earthquakes and floods. Other hazards in the region that cause less damage or happen less frequently include landslides, debris flows, tsunamis, and volcanic eruptions. Although much is known about these natural hazards, mitigation and...
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Honduras flood mapping

Honduras Flood Mapping

Honduras is currently (2001) rebuilding its housing and infrastructure that was destroyed by Hurricane Mitch. To plan responsibly and minimize damage during future floods, the Honduran government needs reliable maps of the areas and depth of inundation by the 50-year flood, the design flood chosen for this project. A systematic method for defining areas and depths of inundation is needed that can...
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Washington Water Science Center
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Honduras Flood Mapping

Honduras is currently (2001) rebuilding its housing and infrastructure that was destroyed by Hurricane Mitch. To plan responsibly and minimize damage during future floods, the Honduran government needs reliable maps of the areas and depth of inundation by the 50-year flood, the design flood chosen for this project. A systematic method for defining areas and depths of inundation is needed that can...
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Puyallup Flood Alert

Puyallup Flood Alert

The Puyallup River Basin lies mostly within Pierce County, Washington, and contains 972 square miles of land ranging in elevation from zero at its mouth in Puget Sound to 14,408 feet at the top of Mount Rainier. The cities of Tacoma, Puyallup, Sumner, and Orting are some of the population centers located in the basin. To protect lives and property in the basin, Pierce County needs accurate...
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Washington Water Science Center
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Puyallup Flood Alert

The Puyallup River Basin lies mostly within Pierce County, Washington, and contains 972 square miles of land ranging in elevation from zero at its mouth in Puget Sound to 14,408 feet at the top of Mount Rainier. The cities of Tacoma, Puyallup, Sumner, and Orting are some of the population centers located in the basin. To protect lives and property in the basin, Pierce County needs accurate...
Learn More