Liam Schenk
Liam Schenk is a hydrologist with the Oregon Water Science center since 2011, with prior work as a hydrologic technician and hydrologist at the USGS Arkansas Water Science Center from 2008-2011. Liam conducts and collaborates on water quality and hydrologic studies in cooperation with federal, state, and local agencies and tribal organizations.
Biography
At the Oregon WSC, Liam is a member of the surface water team and conducts a variety of studies in both fluvial and lentic environments on water quality, sediment and nutrient transport, sediment fingerprinting, sediment transport during deep reservoir drawdowns, and mercury in surface waters. He has worked on projects across Oregon, including in the the Upper Willamette, Deschutes, Malheur, and Klamath basins.
Much of Liam's research is focused on the upper Klamath Basin, evaluating water quality dynamics in Upper Klamath Lake, and assessing nutrient and sediment loading into the lake using turbidity and acoustic backscatter surrogate models and multi-variate weighted regression models. Liam is also evaluating physical variables that effect water quality in upper Klamath Lake using machine learning models, and is on the USGS research team evaluating sediment budgets on the lower Klamath River prior to the anticipated removal of four hydroelectric dams.
Liam received his B.Sc. in Mining Engineering from Colorado School of Mines, and an M.S. in Geology from the University of Arkansas.
Science and Products
Sediment Fingerprinting in the Upper Klamath Basin
Sediment fingerprinting has been used successfully to identify land uses that are the major sources of sediment. This study will apply these techniques in a predominantly rural, volcanic landscape.
Upper Klamath Basin Studies
In 1992, the USGS began studying possible causes for the change in trophic status of Upper Klamath Lake. Since then research has expanded to include groundwater, geomorphology, streamflow forecasting, and fish ecology.
Nutrient and Sediment Loading to Upper Klamath Lake
The USGS employs state-of-the-science techniques to estimate nutrient and suspended-sediment loads to Upper Klamath Lake.
Nutrient Loading to Lost River and Klamath River Subbasins
The USGS has characterized nutrient concentrations in the Klamath River and Lost River drainages over multiple years, identified spatial and temporal patterns in nutrient and organic carbon concentrations, and quantified surface water nutrient loads entering and exiting the Klamath Project.
Sediment transport, turbidity, and dissolved oxygen responses to annual streambed drawdowns for downstream fish passage in a flood control reservoir
Sediment transport, turbidity, and dissolved oxygen were evaluated during six consecutive water years (2013–2018) of drawdowns of a flood control reservoir in the upper Willamette Valley, Oregon, USA. The drawdowns were conducted to allow volitional passage of endangered juvenile chinook salmon through the dam's regulating outlets by lowering...
Schenk, Liam N.; Bragg, Heather M. Effects of harmful algal blooms and associated water-quality on endangered Lost River and shortnose suckers
Anthropogenic eutrophication contributes to harmful blooms of cyanobacteria in freshwater ecosystems worldwide. In Upper Klamath Lake, Oregon, massive blooms of Aphanizomenon flos-aquae and smaller blooms of other cyanobacteria are associated with cyanotoxins, hypoxia, high pH, high concentrations of ammonia, and potentially hypercapnia...
Burdick, Summer M.; Hewitt, David A.; Martin, Barbara A.; Schenk, Liam N.; Rounds, Stewart Monitoring the effect of deep drawdowns of a flood control reservoir on sediment transport and dissolved oxygen, Fall Creek Lake, Oregon
Annual reservoir drawdowns at Fall Creek Lake, Oregon, have occurred for eight consecutive years from December 2012 to November 2019. The annual drawdowns are the result of the 2008 Biological Opinion of the US Army Corps of Engineers (USACE) Willamette Valley Project operations, which directed the USACE to carry out interim operational measures...
Schenk, Liam N.; Bragg, Heather M.
Differentiating sediment sources using sediment fingerprinting techniques, in the Sprague River Basin, South-Central Oregon
Identifying sources of sediment to streams in the Sprague River Basin, in south-central Oregon, is important for restoration efforts that are focused on reducing sediment erosion and transport. Reducing sediment loads in these streams also contributes to compliance with the total maximum daily load reduction requirements for total phosphorus in...
Schenk, Liam N.; Harden, Tessa M.; Kelson, Julia K. Refining the Baseline Sediment Budget for the Klamath River, California
Four dams in the Klamath River Hydroelectric Project (KHP) in Oregon and California (Figure 1) are currently scheduled to be removed over a period of a few weeks or months, beginning in January 2021. The Klamath dam removal will be the largest in the world by almost all measures, and is an unprecedented opportunity to advance science of river...
Anderson, Chauncey W.; Wright, Scott A.; Schenk, Liam N.; Skalak, Katherine; Curtis, Jennifer A.; East, Amy E.; Benthem, Adam
Nutrient loads in the Lost River and Klamath River Basins, south-central Oregon and northern California, March 2012–March 2015
The U.S. Geological Survey and Bureau of Reclamation collected water-quality data from March 2012 to March 2015 at locations in the Lost River and Klamath River Basins, Oregon, in an effort to characterize water quality and compute a nutrient budget for the Bureau of Reclamation Klamath Reclamation Project. The study described in this report...
Schenk, Liam N.; Stewart, Marc A.; Caldwell Eldridge, Sara L.
Evaluating external nutrient and suspended-sediment loads to Upper Klamath Lake, Oregon, using surrogate regressions with real-time turbidity and acoustic backscatter data
Executive SummarySuspended-sediment and total phosphorus loads were computed for two sites in the Upper Klamath Basin on the Wood and Williamson Rivers, the two main tributaries to Upper Klamath Lake. High temporal resolution turbidity and acoustic backscatter data were used to develop surrogate regression models to compute instantaneous...
Schenk, Liam N.; Anderson, Chauncey W.; Diaz, Paul; Stewart, Marc A. Comparison of mercury mass loading in streams to atmospheric deposition in watersheds of Western North America: Evidence for non-atmospheric mercury sources
Annual stream loads of mercury (Hg) and inputs of wet and dry atmospheric Hg deposition to the landscape were investigated in watersheds of the Western United States and the Canadian-Alaskan Arctic. Mercury concentration and discharge data from flow gauging stations were used to compute annual mass loads with regression models. Measured wet and...
Domagalski, Joseph L.; Majewski, Michael S.; Alpers, Charles N.; Eckley, Chris S.; Eagles-Smith, Collin A.; Schenk, Liam N.; Wherry, Susan
Assessment of suspended-sediment transport, bedload, and dissolved oxygen during a short-term drawdown of Fall Creek Lake, Oregon, winter 2012-13
The drawdown of Fall Creek Lake resulted in the net transport of approximately 50,300 tons of sediment from the lake during a 6-day drawdown operation, based on computed daily values of suspended-sediment load downstream of Fall Creek Dam and the two main tributaries to Fall Creek Lake. A suspended-sediment budget calculated for 72 days of the...
Schenk, Liam N.; Bragg, Heather M.
Water-quality data from Upper Klamath and Agency Lakes, Oregon, 2009-10
The U.S. Geological Survey Upper Klamath Lake water-quality monitoring program collected data from multiparameter continuous water-quality monitors, weekly water-quality samples, and meteorological stations during 2009 and 2010 from May through November each year. The results of these measurements and sample analyses, as well as quality-control...
Eldridge, D. Blake; Caldwell Eldridge, Sara L.; Schenk, Liam N.; Tanner, Dwight Q.; Wood, Tamara M.
USGS Uses State-of-the-Art Science to Estimate Nutrient and Suspended-Sediment Loads in the Klamath Basin
USGS uses state-of-the-art science techniques to estimate phosphorus and suspended-sediment loads to Upper Klamath Lake in the Klamath Basin.