Geology topics

Andrew D. Ebner

Publications and source records attributed to Andrew D. Ebner.

9 recordsLinked to original sources

USGS2015

Hydrologic effects of potential changes in climate, water use, and land cover in the Upper Scioto River Basin, Ohio

This report presents the results of a study to provide information on the hydrologic effects of potential 21st-century changes in climate, water use, and land cover in the Upper Scioto River Basin, Ohio (from Circleville, Ohio, to the headwaters). A precipitation-runoff model, calibrated on the basis of historical climate and streamflow data, was used to simulate the effects of climate change on streamflows and reservoir water levels at several locations in the basin. Two levels of simulations were done. The first level of simulation (level 1) accounted only for anticipated 21st-century changes in climate and operations of three City of Columbus upground reservoirs located in northwest Delaware County, Ohio. The second level of simulation (level 2) accounted for development-driven changes in land cover and water use in addition to changes in climate and reservoir operations. A statistical change-factor approach was used to construct future climate time series that were used in the precipitation-runoff model to compute time series of future streamflows and reservoir water levels. Monthly change factors were computed by determining differences or fractional changes between baseline historical climate time series and future climate time series consisting of outputs from selected global climate models that were included in the World Climate Research Programme’s Coupled Model Intercomparison Project phase 3 (CMIP3). Eight sets of change factors were determined on the basis of outputs from four global climate models, each of which was run under two greenhouse-gas scenarios (the “A1b” and “A2” scenarios from the Intergovernmental Panel on Climate Change’s 4th assessment). The 4 global climate models whose data were used in this study were selected to represent a wide range of potential climate outcomes as compared to the entire range of potential climate outcomes associated with the 16 global climate models represented in the CMIP3 multimodel dataset. Future land-cover and water-use data were estimated for use in the level-2 precipitation-runoff simulations to account for development-driven changes in land cover and water use. Future land-cover characteristics were estimated for selected future years based on population projections and zoning plans for communities in the basin. Future water-use data for major water suppliers and wastewater-treatment facilities were estimated from current per capita water use, population projections for 2035, and population projections for 2090 assuming full build-out. A statistical change-factor-based approach was used to estimate future water-use characteristics by major water suppliers and wastewater-treatment facilities on the basis of reference-period historical water uses. Annual change factors that were determined for future years other than 2035 and 2090 (when the change factors could be explicitly computed) were estimated by interpolating or extrapolating linearly in time. Water uses by entities other than major water suppliers and wastewater-treatment facilities were assumed to remain unchanged because of uncertainty about if and (or) how they might change. Results from the level-1 simulations were analyzed primarily to facilitate evaluation of climate-driven temporal changes in annual, seasonal, and monthly streamflow and water-level characteristics, as well as in maximum and minimum 7-, 30-, and 180-day average streamflow and reservoir water levels. Results from the level-2 simulations were analyzed to help evaluate and contrast (relative to level-1 results) the effects of the added development-related factors on maximums and minimum 7-, 30-, and 180-day average streamflows and reservoir water levels and duration characteristics of 7- and 30-day average streamflows and reservoir water levels. Results for 12 stream locations and 5 reservoirs in the Upper Scioto River Basin are presented primarily as a series of plots. Although it is beyond the scope of this study to address results in detail for each model-output location, selected results are discussed to illustrate potential uses and interpretations of the graph products provided in this report. In addition, general trends and patterns in streamflow and water-level characteristics are identified where possible.

Ohio↗

USGS2011

Stream profile analyses using a step-backwater model for selected reaches in the Chippewa Creek Basin in Medina, Wayne, and Summit Counties, Ohio

The USGS, in cooperation with the Chippewa Subdistrict of the Muskingum Watershed Conservancy District, performed hydrologic and hydraulic analyses for selected reaches of three streams in Medina, Wayne, Stark, and Summit Counties in northeast Ohio: Chippewa Creek, Little Chippewa Creek, and River Styx. This study was done to facilitate assessment of various alternatives for mitigating flood hazards in the Chippewa Creek basin. StreamStats regional regression equations were used to estimate instantaneous peak discharges approximately corresponding to bankfull flows. Explanatory variables used in the regression equations were drainage area, main-channel slope, and storage area. Hydraulic models were developed to determine water-surface profiles along the three stream reaches studied for the bankfull discharges established in the hydrologic analyses. The HEC-RAS step-backwater hydraulic analysis model was used to determine water-surface profiles for the three streams. Starting water-surface elevations for all streams were established using normal depth computations in the HEC-RAS models. Cross-sectional elevation data, hydraulic-structure geometries, and roughness coefficients were collected in the field and (along with peak-discharge estimates) used as input for the models. Reach-averaged reductions in water-surface elevations ranged from 0.11 to 1.29 feet over the four roughness coefficient reduction scenarios.

Ohio↗

USGS2009

Floods of August 21-24, 2007, in Northwestern and North-Central Ohio

Heavy rains in northwestern and north-central Ohio on August 19-22, 2007, caused severe flooding and widespread damages to residential, public, and commercial structures in the communities of Bluffton, Bucyrus, Carey, Columbus Grove, Crestline, Findlay, Mansfield, Ottawa, and Shelby. On August 27, 2007, the Federal Emergency Management Agency (FEMA) issued a notice of a Presidential declaration of a major disaster affecting Allen, Crawford, Hancock, Hardin, Putnam, Richland, Seneca, and Wyandot Counties as a result of the severe flooding. Rainfall totals for most of the flooded area were 3 to 5 in., with some locations reporting as much as 8 to 10 in. Three National Weather Service (NWS) gages in the area indicated a rainfall recurrence interval of greater than 1,000 years, and two indicated a recurrence interval between 500 and 1,000 years. Total damages are estimated at approximately $290 million, with 8,205 residences registering for financial assistance. The U.S. Geological Survey (USGS) computed flood recurrence intervals for peak streamflows at 22 streamgages and 8 ungaged sites in and around the area of major flooding. The peak streamflows at Sandusky River near Bucyrus streamgage and at seven of the eight ungaged sites had estimated recurrence intervals of greater than 500 years. The USGS located and surveyed 421 high-water marks and plotted high-water profiles for approximately 44.5 miles of streams throughout the nine communities.

Open-File Report↗

USGS2008

Floods of December 2004 and January 2005 in Ohio: FEMA Disaster Declaration 1580

A large snowstorm at the end of December 2004 that left more than 20 inches of snow in some areas of Ohio, followed by unseasonably warm temperatures in early January 2005, caused snowmelt to begin filling river channels. Widespread rain showers during January 2005 combined with this snowmelt to cause flooding throughout Ohio and mudslides in some areas. Record peak streamflows occurred at nine U.S. Geological Survey (USGS) streamgages. Damages caused by the snowstorms, flooding, and mudslides were severe enough for 62 counties in Ohio to be declared Federal disaster areas. In all, approximately 3,664 private structures were damaged or destroyed, and an estimated $238 million in damages occurred. This report describes the meteorological factors that resulted in severe flooding throughout Ohio between December 22, 2004, and February 1, 2005, and examines the damages caused by the storms and flooding. Peak-stage, peak-streamflow, and recurrence-interval data are reported for selected USGS streamgages. Flood profiles determined by the USGS are presented for selected streams.

Ohio↗

USGS2008

Floods of May and June 2004 in central and eastern Ohio: FEMA disaster declaration 1519

Several severe thunderstorms that passed through Ohio between May 17 and June 17, 2004, produced large amounts of rain in an already wet central and eastern Ohio, resulting in flooding in this region from May 18 to June 21, 2004. Record peak streamflow occurred at three U.S. Geological Survey (USGS) streamgages. Damages caused by the flooding resulting from these storms were severe enough that 25 counties in central and eastern Ohio were declared Federal disaster areas. In all, there were two storm- or flood-related deaths, 3,529 private structures damaged or destroyed, and an estimated $43 million in damages. This report describes the meteorological factors that resulted in severe flooding in central and eastern Ohio between May 18 and June 21, 2004, and addresses the damages caused by the storms and flooding. Peak-stage, peak-streamflow, and recurrence-interval data are reported for selected USGS streamgages. Flood profiles determined by the USGS are presented for selected streams.

Ohio↗

USGS2008

Floods of August and September 2004 in eastern Ohio: FEMA disaster declaration 1556

A band of severe thunderstorms at the end of August 2004 and the passage of the remnants of Hurricanes Frances and Ivan during September 2004 caused severe flooding in eastern Ohio during August and September 2004. Record peak streamflow occurred at 12 U.S. Geological Survey (USGS) streamgages. Damages caused by the flooding produced by these storms were severe enough for 21 counties in eastern Ohio to be declared Federal disaster areas. In all, there were 4 storm- or flood-related deaths, 2,563 private structures damaged or destroyed, and an estimated $81 million in damages. This report describes the meteorological factors that resulted in severe flooding in eastern Ohio during August 27-September 27, 2004, and examines the damages caused by the storms and flooding. Peak-stage, peak-streamflow, and recurrence-interval data are reported for selected USGS streamgages. Flood profiles determined by the USGS are presented for selected streams.

Ohio↗

USGS2008

Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio

The USGS, in cooperation with the Ohio Emergency Management Agency, conducted a study in the Wheeling Creek Basin to (1) evaluate and contrast land-cover characteristics from 2001 with characteristics from 1979 and 1992; (2) compare current streambed elevation, slope, and geometry with conditions present in the late 1980s; (3) look for evidence of channel filling and over widening in selected undredged reaches; (4) estimate flood elevations for existing conditions in both undredged and previously dredged reaches; (5) evaluate the height of the levees required to contain floods with selected recurrence intervals in previously dredged reaches; and (6) estimate flood elevations for several hypothetical dredging and streambed aggradation scenarios in undredged reaches. The amount of barren land in the Wheeling Creek watershed has decreased from 20 to 1 percent of the basin area based on land-cover characteristics from 1979 and 2001. Barren lands appear to have been converted primarily to pasture, presumably as a result of surface-mine reclamation. Croplands also decreased from 13 to 8 percent of the basin area. The combined decrease in barren lands and croplands is approximately offset by the increase in pasture. Stream-channel surveys conducted in 1987 and again in 2006 at 21 sites in four previously dredged reaches of Wheeling Creek indicate little change in the elevation, slope, and geometry of the channel at most sites. The mean change in width-averaged bed and thalweg elevations for the 21 cross sections was 0.1 feet. Bankfull widths, mean depths, and cross-sectional areas measured at 12 sites in undredged reaches were compared to estimates determined from regional equations. The mean percentage difference between measured and estimated bankfull widths was -0.2 percent, suggesting that bankfull widths in the Wheeling Creek Basin are generally about the same as regional averages for undisturbed basins of identical drainage area. For bankfull mean depth and cross-sectional area, the mean percentage differences between the measured and estimated values were -16.0 and -11.2, respectively. The predominantly negative bias in differences between the measured and estimated values indicates that bankfull mean depths and cross-sectional areas in studied reaches generally are smaller than the regional trend. This may be an indication of channel filling and over widening or it may reflect insufficient representation in the regional dataset of basins with characteristics like that of Wheeling Creek. Step-backwater models were constructed for four previously dredged reaches to determine the height of levees required to contain floods with recurrence intervals of 2, 10, 50, and 100 years. Existing levees (all of which are uncertified) were found to contain the 100-year flood at only 20 percent of the surveyed cross sections. At the other 80 percent of the surveyed cross sections, levee heights would have to be raised an average of 2.5 feet and as much as 6.3 feet to contain the 100-year flood. Step-backwater models also were constructed for three undredged reaches to assess the impacts of selected dredging and streambed aggradation scenarios on water-surface elevations corresponding to the 2-, 10-, 50-, and 100-year floods. Those models demonstrated that changes in water-surface elevations associated with a given depth of dredging were proportionately smaller for larger floods due to the fact that more of the flood waters are outside of the main channel. For example, 2.0 feet of dredging in the three study reaches would lower the water-surface elevation an average of 1.30 feet for the 2-year flood and 0.64 feet for the 100-year flood.

Scientific Investigations Report↗

USGS2007

Flood of July 27-31, 2006, on the Grand River near Painesville, Ohio

Two separate weather systems produced storms resulting in more than 11 inches of rain in parts of Lake County, Ohio, on July 27-28, 2006. As a result of the storms and ensuing flooding caused by the weather systems, the counties of Lake, Geauga, and Ashtabula were declared Federal and State disaster areas, with damages estimated at $30 million and one fatality in Lake County. About 600 people were evacuated in Lake County. The U.S. Geological Survey streamflow-gaging station at Grand River near Painesville, Ohio (station 04212100), had a record peak stage of 19.35 feet (elevation, 614.94 feet), with a record peak streamflow of 35,000 cubic feet per second, and an estimated recurrence interval of approximately 500 years. This report describes the meteorological factors that resulted in severe flooding on the Grand River near Painesville from July 27 to July 31, 2006, and addresses the damages caused by the storms and flooding. Peak-stage, peak-streamflow, and recurrence-interval data are reported for the Grand River near Painesville. A plot of high-water marks is also presented for the Grand River in a reach that includes the City of Painesville, Painesville Township, the Village of Fairport Harbor, and the Village of Grand River.

Open-File Report↗

USGS2007

Flood of June 22-24, 2006, in North-Central Ohio, With Emphasis on the Cuyahoga River Near Independence

Heavy rains caused severe flooding on June 22-24, 2006, and damaged approximately 4,580 homes and 48 businesses in Cuyahoga County. Damage estimates in Cuyahoga County for the two days of flooding exceed $47 million; statewide damage estimates exceed $150 million. Six counties (Cuyahoga, Erie, Huron, Lucas, Sandusky, and Stark) in northeast Ohio were declared Federal disaster areas. One death, in Lorain County, was attributed to the flooding. The peak streamflow of 25,400 cubic feet per second and corresponding peak gage height of 23.29 feet were the highest recorded at the U.S. Geological Survey (USGS) streamflow-gaging station Cuyahoga River at Independence (04208000) since the gaging station began operation in 1922, exceeding the previous peak streamflow of 24,800 cubic feet per second that occurred on January 22, 1959. An indirect calculation of the peak streamflow was made by use of a step-backwater model because all roads leading to the gaging station were inundated during the flood and field crews could not reach the station to make a direct measurement. Because of a statistically significant and persistent positive trend in the annual-peak-streamflow time series for the Cuyahoga River at Independence, a method was developed and applied to detrend the annual-peak-streamflow time series prior to the traditional log-Pearson Type III flood-frequency analysis. Based on this analysis, the recurrence interval of the computed peak streamflow was estimated to be slightly less than 100 years. Peak-gage-height data, peak-streamflow data, and recurrence-interval estimates for the June 22-24, 2006, flood are tabulated for the Cuyahoga River at Independence and 10 other USGS gaging stations in north-central Ohio. Because flooding along the Cuyahoga River near Independence and Valley View was particularly severe, a study was done to document the peak water-surface profile during the flood from approximately 2 miles downstream from the USGS streamflow-gaging station at Independence to approximately 2 miles upstream from the gaging station. High-water marks were identified and flagged in the field. Third-order-accuracy surveys were used to determine elevations of the high-water marks, and the data were tabulated and plotted.

Scientific Investigations Report↗