Luther Schalk (Former Employee)
Science and Products
Methods for computing 7Q2 and 7Q20 low-streamflow statistics to account for possible trends
Low-streamflow statistics, such as the annual minimum 7-day streamflow (which is the 7-day streamflow likely to be exceeded in 9 out of 10 years on average [7Q10]), that are computed by using the full historical streamflow record may not accurately represent current conditions at sites with statistically significant trends in low streamflow over time. Recent research suggests that using a contempo
Authors
Luther Schalk, Robert W. Dudley, Annalise G. Blum
Methods of collection and quality assessment of arsenic data in well-water supplies in Maine, 2001–2 and 2006–7
The U.S. Geological Survey, in cooperation with the U.S. Centers for Disease Control and Prevention and the Maine Center for Disease Control and Prevention, assessed the chemical characteristics and the occurrence, distribution, and oxidation state of inorganic arsenic in drinking water from selected domestic well-water supplies in Maine in 2001–2 and 2006–7.The data collected provide support for
Authors
Charles W. Culbertson, James M. Caldwell, Luther Schalk, Deana Manassaram, Lorraine C. Backer, Andrew E. Smith
Framework for a hydrologic climate-response network in New England
Many climate-related hydrologic variables in New England have changed in the past century, and many are expected to change during the next century. It is important to understand and monitor these changes because they can affect human water supply, hydroelectric power generation, transportation infrastructure, and stream and riparian ecology. This report describes a framework for hydrologic monitor
Authors
Robert M. Lent, Glenn A. Hodgkins, Robert W. Dudley, Luther Schalk
Velocity, water-quality, and bathymetric surveys of the Grays Landing and Maxwell Navigation Pools, and Selected Tributaries to the Monongahela River, Pennsylvania, 2010–11
The U.S. Geological Survey (USGS) conducted velocity, water-quality, and bathymetric surveys from spring 2010 to summer 2011 in the Grays Landing and Maxwell navigation pools of the Monongahela River, Pennsylvania, and selected tributaries in response to elevated levels of total dissolved solids (TDS) recorded in early September 2009. Velocity data were collected using an Acoustic Doppler Current
Authors
Scott A. Hoffman, Mark A. Roland, Luther Schalk, John W. Fulton
Relations between winter climatic variables and April streamflows in New England and implications for summer streamflows
A period of much below normal streamflow in southern New England during April 2012 raised concerns that a long-term period of drought could evolve through late spring and summer, leading to potential water availability issues. To understand better the relations between winter climatic variables and April streamflows, April streamflows from 31 streamflow gages in New England that drain relatively n
Authors
Glenn A. Hodgkins, Robert W. Dudley, Luther Schalk
Assessment of arsenic concentrations in domestic well water, by town, in Maine 2005-09
Prior studies have established that approximately 10 percent of domestic wells in Maine have arsenic levels greater than the U.S. Environmental Protection Agency maximum contaminant limit (10 micrograms per liter (ug/L)). Of even greater concern are multiple discoveries of wells with very high arsenic levels (> 500 ug/L) in several areas of the State. A study was initiated to assist the Maine Cent
Authors
M.G. Nielsen, P.J. Lombard, L.F. Schalk
Arsenic datasets and other physical and chemical measurements for selected domestic well-water supplies in Maine: 2001-2 and 2006-7
The U.S. Geological Survey (USGS), in cooperation with the U.S. Centers for Disease Control and Prevention and the Maine Center for Disease Control and Prevention, assessed the physical and chemical characteristics and the occurrence, distribution, and oxidation state of inorganic arsenic in drinking water from selected domestic well-water supplies in Maine in 2001-2 and 2006-7. The data collected
Science and Products
Methods for computing 7Q2 and 7Q20 low-streamflow statistics to account for possible trends
Low-streamflow statistics, such as the annual minimum 7-day streamflow (which is the 7-day streamflow likely to be exceeded in 9 out of 10 years on average [7Q10]), that are computed by using the full historical streamflow record may not accurately represent current conditions at sites with statistically significant trends in low streamflow over time. Recent research suggests that using a contempo
Authors
Luther Schalk, Robert W. Dudley, Annalise G. Blum
Methods of collection and quality assessment of arsenic data in well-water supplies in Maine, 2001–2 and 2006–7
The U.S. Geological Survey, in cooperation with the U.S. Centers for Disease Control and Prevention and the Maine Center for Disease Control and Prevention, assessed the chemical characteristics and the occurrence, distribution, and oxidation state of inorganic arsenic in drinking water from selected domestic well-water supplies in Maine in 2001–2 and 2006–7.The data collected provide support for
Authors
Charles W. Culbertson, James M. Caldwell, Luther Schalk, Deana Manassaram, Lorraine C. Backer, Andrew E. Smith
Framework for a hydrologic climate-response network in New England
Many climate-related hydrologic variables in New England have changed in the past century, and many are expected to change during the next century. It is important to understand and monitor these changes because they can affect human water supply, hydroelectric power generation, transportation infrastructure, and stream and riparian ecology. This report describes a framework for hydrologic monitor
Authors
Robert M. Lent, Glenn A. Hodgkins, Robert W. Dudley, Luther Schalk
Velocity, water-quality, and bathymetric surveys of the Grays Landing and Maxwell Navigation Pools, and Selected Tributaries to the Monongahela River, Pennsylvania, 2010–11
The U.S. Geological Survey (USGS) conducted velocity, water-quality, and bathymetric surveys from spring 2010 to summer 2011 in the Grays Landing and Maxwell navigation pools of the Monongahela River, Pennsylvania, and selected tributaries in response to elevated levels of total dissolved solids (TDS) recorded in early September 2009. Velocity data were collected using an Acoustic Doppler Current
Authors
Scott A. Hoffman, Mark A. Roland, Luther Schalk, John W. Fulton
Relations between winter climatic variables and April streamflows in New England and implications for summer streamflows
A period of much below normal streamflow in southern New England during April 2012 raised concerns that a long-term period of drought could evolve through late spring and summer, leading to potential water availability issues. To understand better the relations between winter climatic variables and April streamflows, April streamflows from 31 streamflow gages in New England that drain relatively n
Authors
Glenn A. Hodgkins, Robert W. Dudley, Luther Schalk
Assessment of arsenic concentrations in domestic well water, by town, in Maine 2005-09
Prior studies have established that approximately 10 percent of domestic wells in Maine have arsenic levels greater than the U.S. Environmental Protection Agency maximum contaminant limit (10 micrograms per liter (ug/L)). Of even greater concern are multiple discoveries of wells with very high arsenic levels (> 500 ug/L) in several areas of the State. A study was initiated to assist the Maine Cent
Authors
M.G. Nielsen, P.J. Lombard, L.F. Schalk
Arsenic datasets and other physical and chemical measurements for selected domestic well-water supplies in Maine: 2001-2 and 2006-7
The U.S. Geological Survey (USGS), in cooperation with the U.S. Centers for Disease Control and Prevention and the Maine Center for Disease Control and Prevention, assessed the physical and chemical characteristics and the occurrence, distribution, and oxidation state of inorganic arsenic in drinking water from selected domestic well-water supplies in Maine in 2001-2 and 2006-7. The data collected