Hydraulic Modeling of Glacial Dam-Break Floods on the West Branch of the Susquehanna River, Pennsylvania

This study investigates the potential hydraulic conditions of catastrophic floods in the West Branch of the Susquehanna River (West Branch) during the middle to late Pleistocene period and the influence of these paleofloods on the current river bed form. The current channel bed form is characterized using sonar bathymetry data collection techniques. The paleofloods are hypothesized based on published geological evidence of early Pleistocene glacial Lake Lesley in the West Branch Valley, which was formed by a glacial ice dam that potentially failed during mild climate cycles in the Pleistocene period. A one-dimensional, steady hydraulic model is developed to simulate estimates of paleoflood peak discharges and the modern 100 year return period peak discharge. The computed water-surface profiles, shear stresses, and flood inundation maps could explain the erosional and depositional features identified by other researchers as being formed during the Pleistocene and could explain features revealed by the bathymetry data. Therefore, the hydraulic modeling results support previously inferred hypotheses of the occurrence of glacial dam-break floods on the West Branch of the Susquehanna River. The differences that are evident between the paleoflood simulations and the simulation of the modern 100 year peak discharge are attributable to valley constrictions that cause substantial backwater effects for the larger paleoflood discharges but not for the lower modern flood discharge volume. The ability to simulate potential paleofloods in the West Branch of the Susquehanna River complements the paleostage indicator work done by other researchers and enables innovative analysis of glaciofluvial processes and their effect on the current river bed form

Post-Flood Cleanup Alternatives along Stream Corridors in Central Pennsylvania Helping Resolve River and Land Use Conflicts in an Economically and Ecologically Sustainable Manner

Report on managing river corridors of Central Pennsylvania in an economically and ecologically sustainable manner. Fluvial geomorphologists and civil engineers from Bucknell University present results of research and analysis of the impact of floods on Central Pennsylvania streams, bridges, dams, and roads. Ten sections cover 1. Key Concepts for Managing River Corridors in a Sustainable Manner; 2. Options for Managing the Conflict between Nature and Man; 3. The Physical Imperatives of River Systems; 4. Dynamic Equilibrium of Streams and Anticipating Adjustments in the Future; 5. The Conflict: Today’s Accounting; 6. Cost-Benefit Analysis; 7. Short vs. Long Term Solutions: A Choice of Management Scenarios; 8. “Stream-Cleaning” – allow gravel or “do nothing”? 9. Informing the Alternative Selection Process; 10. Managing Sustainably. The report focuses on the long term benefits of a geomorphic corridor management approach which can benefit both property owners and riparian ecosystems. The largest challenge is not in conducting the scientific analyses to determine the river’s slope and planform requirements, but rather in how to redefine the relationship of public and private investments with fluvial dynamics in an equitable manner over time within a watershed. The larger short term costs associated with using a geomorphic-based approach, where land conversion is necessary, become more acceptable and economically justifiable where channelization projects have failed repeatedly or in post flood remediation where major erosion, property damage, and channel avulsions have occurred. A passive geomorphic approach may be the most desirable alternative due to its lower maintenance costs but is highly dependent upon landowners willing to accept what may be significant changes in land use expectations. Concluding recommendations exhort State and Federal agencies involved with river resource management to work together to provide economic incentives and technical assistance for towns and landowners to make decisions that resolve immediate conflicts with the long term watershed solutions in mind

Psychosocial impact of undergoing prostate cancer screening for men with BRCA1 or BRCA2 mutations.

OBJECTIVES: To report the baseline results of a longitudinal psychosocial study that forms part of the IMPACT study, a multi-national investigation of targeted prostate cancer (PCa) screening among men with a known pathogenic germline mutation in the BRCA1 or BRCA2 genes. PARTICPANTS AND METHODS: Men enrolled in the IMPACT study were invited to complete a questionnaire at collaborating sites prior to each annual screening visit. The questionnaire included sociodemographic characteristics and the following measures: the Hospital Anxiety and Depression Scale (HADS), Impact of Event Scale (IES), 36-item short-form health survey (SF-36), Memorial Anxiety Scale for Prostate Cancer, Cancer Worry Scale-Revised, risk perception and knowledge. The results of the baseline questionnaire are presented. RESULTS: A total of 432 men completed questionnaires: 98 and 160 had mutations in BRCA1 and BRCA2 genes, respectively, and 174 were controls (familial mutation negative). Participants' perception of PCa risk was influenced by genetic status. Knowledge levels were high and unrelated to genetic status. Mean scores for the HADS and SF-36 were within reported general population norms and mean IES scores were within normal range. IES mean intrusion and avoidance scores were significantly higher in BRCA1/BRCA2 carriers than in controls and were higher in men with increased PCa risk perception. At the multivariate level, risk perception contributed more significantly to variance in IES scores than genetic status. CONCLUSION: This is the first study to report the psychosocial profile of men with BRCA1/BRCA2 mutations undergoing PCa screening. No clinically concerning levels of general or cancer-specific distress or poor quality of life were detected in the cohort as a whole. A small subset of participants reported higher levels of distress, suggesting the need for healthcare professionals offering PCa screening to identify these risk factors and offer additional information and support to men seeking PCa screening

Sediment Depostion Near Bridges in Pennsylvania

Gravel bed streams across central Pennsylvania often have problems related to large quantities of transported bed material. The natural movement of sediment can be disturbed when bridge structures are placed across a stream channel or a channel is modi?e

Hydraulic Interaction between Rock Cross Vane Stream Restoration Structures and a Bridge Crossing

The performance of a stream restoration project that incorporates a bridge crossing is evaluated within a 3-year monitoring period. A goal of the project was to alleviate and prevent future sediment aggradation within the waterway of a low-clearance bridge crossing. The stream restoration project included two rock cross vanes and stepped riprap and vegetation bank stabilization. Monitoring of the project involved the collection of channel survey data, pebble counts, and general observations of instream structure condition and sediment movement. The evaluated performance of the restoration structures is related to the general hydrologic conditions, the historical changes in the watershed and channel, and the hydraulic conditions created by the low-clearance bridge crossing. Backwater effects created by the bridge crossing are found to be a substantial cause of the failure of the stream restoration project to meet its goals. The low-clearance bridge hydraulics are preventing a rock cross vane located upstream of the bridge from creating a scour hole in the centre of the channel; instead, aggradation is occurring in this portion of the channel. However, degradation is occurring downstream of the bridge causing the failure of the second rock cross vane and of the riprap and vegetation bank. Although the hydraulic conditions may stem from the initial design of the bridge crossing, any restoration structure should be designed according to the current site hydraulics. In addition to providing insight into the design and construction of stream restoration structures, the results have implications for the design and management of bridge crossings. Copyright (c) 2014 John Wiley & Sons, Ltd

River Bed Characterization on the West Branch of the Susquehanna River with Side Scan Sonar

Channel formation and maintenance processes for river form and habitat creation depend greatly on the ability of discharges to transport and distribute sediments of particular sizes. Commonly-used methods for sediment size determination (e.g. pebble counts and sample collection with a dredge device) have limitations for use in large river environments with substantial gravel- and cobble-sized bed sediment such as the West Branch of the Susquehanna River. Side scan sonar and photogrammetry methods are being used to conduct a large-scale characterization of bed material size and spatial distribution of sediments on the bed of the river. A 5-km reach of the West Branch of the Susquehanna River is identified as a test section for the application of the side scan sonar. A Lowrance® HDS-10 Gen2 system with StructureScan® is used to collect extensive sonar imagery of the bed of the river. The collected data are processed with the SonarTRX and ArcGIS software to develop a complete sonar image of the river bed. The characterization of river bed sediments and distribution patterns on a section of the West Branch of the Susquehanna River provides necessary data for the interpretation of channel formation due to modern floods and paleofloods in the region and for aquatic ecologists interested evaluating benthic habitat within the river

Water Temperature Variability in the West Branch of the Susquehanna River and Its Tributaries

The water temperature and hydraulic characteristics of a river create environments that support complex habitats within the river and its tributaries. Measurements of water temperature are collected using a network of over fifty HOBO Pendant® data loggers placed in the West Branch of the Susquehanna River (WBSR) and its tributaries. Analyses of water temperature variations achieve several goals, including (1) mapping of the spatial variability in water temperature in the West Branch of the Susquehanna River, (2) identification of primary groundwater inflow sources to the WBSR, and (3) general characterization of hydraulic mixing where smaller tributaries enter the main river. A broadly-spaced network of water temperature data loggers in the WBSR is being used to better characterize general longitudinal and cross-channel temperature variability. Methods are developed for mapping of longitudinal transects of the WBSR from Muncy, PA to Winfield, PA using a SonTek RiverSurveyor® M9 system in combination with In-Situ and Solinst data loggers. In combination with geologic data and field observation, analyzing near- bed temperature, water-surface temperature, water conductivity levels, and general temperature mapping identifies potential groundwater inflow sources to the river. A detailed network with data loggers more closely spaced is installed at major tributary confluences with the main river to allow for the characterization of hydraulic mixing at these locations. Overall, this collection of water temperature variability and velocity data on the West Branch of the Susquehanna River and its tributaries serves as an initial step in understanding the hydraulic dynamics necessary for proper river and stream management decisions that consider the long-term sustainability of the river\u27s ecosystem processes

Use of Hydro-Acoustics in Undergraduate Teaching and Research: Measuring Flow Hydraulics, River Bedforms, and Sediment Discharge in the Susquehanna Watershed, North-Central Pennsylvania

The use of hydro-acoustic methods has greatly enhanced existing watershed-based courses by providing students the opportunity to learn ADCP technologies and compare it to traditional methods using Price-type AA bucket wheel and Marsh-McBirney™ electromag