Understanding the interconnections between oceanic-atmospheric climate variables and regional streamflow of the conterminous United States may aid in improving regional long lead-time streamflow forecasting. The current research evaluates the time-lagged relationship between streamflow of six geographical regions defined from National Climate Assessment and sea surface temperature (SST), 500-mbar geopotential height (Z₅₀₀), 500-mbar specific humidity (SH₅₀₀), and 500-mbar east-west wind (U₅₀₀) of the Pacific and the Atlantic Ocean using singular value decomposition (SVD). The spatio-temporal correlation between streamflow and SST was developed first from SVD and thus obtained correlation was later associated with Z₅₀₀, SH₅₀₀, and U₅₀₀ separately to evaluate the coupled interconnections between the climate variables. Furthermore, the associations between regional streamflow and the El Niño Southern Oscillation (ENSO), Pacific Decadal Oscillation, and Atlantic Multidecadal Oscillation were evaluated using the derivatives of continuous wavelet transform. Regional SVD analysis revealed significant teleconnection between several regions and climate variables. The warm phase of equatorial SST had shown a stronger correlation with the majority of streamflow. Both SVD and wavelet analyses concluded that the streamflow variability of the regions in close proximity to the Pacific Ocean was strongly associated with the ENSO. Improved knowledge of teleconnection of climate variables with regional streamflow variability may help in regional water management and streamflow prediction studies.

Hurricane-induced flooding is a recurring phenomenon causing severe damages to lives and properties in southern coastal states. The magnitude of rainfall observed during Harvey Hurricane in August 2017 was the all-time maximum for some of the regions in Houston, TX. This research focuses on modeling different recurrence frequency flows in a selected river reach along with the Harvey flooding condition. The statistical part involves the flood frequency analysis using generalized extreme value distribution. The floodplain analysis is performed by developing a hydraulic model using Hydraulic Engineering Center’s River Analysis System and Esri ArcMap software. Historical flow data and terrain geometric data are extracted from United States Geological Survey. A river reach of Buffalo Bayou is selected and analyzed for several flow scenarios, and flood inundation map of the affected region is developed. The model is calibrated and validated for river stage by adjusting Manning’s roughness coefficient. The evaluation of each flood stage and comparison with the Harvey flooding stage is expected to provide valuable information for floodplain management, riverside development, and for future flood assessment plans in the adjoining areas.

Urbanization and land development in Ellicott City, Maryland, has led to flooding twice in the past five years. Flooding, resulting from the Patapsco River catchment area and excess precipitation, has been devastating to this East Coast town. Low impact development (LID) designs in urban storm water drainage can lower peak discharges during flood events. LID practices consist of material and construction designs such as permeable pavements for parking lots and sidewalks, green rooftops, rain gardens, retention cisterns, and natural rehabilitation. This study utilizes Environmental Protection Agency Storm Water Management Modeling (EPA SWMM) software to model the catchment area while implementing LID land areas. SWMM is capable of implementing LID practices such as permeable pavements and grass ways in the existing landscape in the catchment area. Watershed was delineated with the aid of geographic information systems and soil and water assessment tool. United States Geological Survey river gauge station provided stream discharge information needed for flow volume estimates. National Oceanic and Atmospheric Administration precipitation records for different storm events were routed through the catchment area for peak flood scenarios. Existing land use and implementation of LID scenarios were compared resulting in an EPA SWMM prediction of flood reduction of 5.4% and 7.5% with the use of green roofs and permeable pavements, respectively for the considered storm event. This study showed LID designs have the potential to reduce flood peak, resulting in economic and social benefits.

Is sea level change affected by the presence of autocorrelation and abrupt shift? This question reflects the importance of trend and shift detection analysis in sea level. The primary factor driving the global sea level rise is often related to climate change. The current study investigates the changes in sea level along the US coast. The sea level records of 59 tide gauge data were used to evaluate the trend, shift, and persistence using non-parametric statistical tests. Mann-Kendall and Pettitt’s tests were utilized to estimate gradual trends and abrupt shifts, respectively. The study also assessed the presence of autocorrelation in sea level records and its effect on both trend and shift was examined along the US coast. The presence of short-term persistence was found in 57 stations and the trend significance of most stations was not changed at a 95% confidence level. Total of 25 stations showed increasing shift between 1990–2000 that was evaluated from annual sea level records. Results from the current study may contribute to understanding sea level variability across the contiguous US. This study extends an elaborative understanding of sea level trends and shifts which might be useful for water managers.

River ice cover is a reoccurring phenomenon in the Northern United States every year. Sheets and layers of ice result in a rise of water surface elevation and may lead to ice jams in a river. This research explains the modeling of a river reach through Northern Illinois containing a structural weir and how the water profile is effected during ice cover and ice jam events. The Hydraulic Engineering Center’s River Analysis System was used in conjunction with Esri ArcMap software to model a portion of the river for analysis. The study area of the Rock River flowing through Oregon, IL, is known to freeze and ice over during the winter months in Northern Illinois. Data from the United States Geological Survey and National Oceanic and Atmospheric Administration were utilized to obtain cross-section and discharge measurements. The impacts of an ice jam occurring upstream of the weir and downstream of the weir were studied. The effects of the ice jam on the upstream water levels were also evaluated to observe if any flooding may occur inside the town or even farther upstream. Results of the ice cover and ice jam data were then compared to those of the Rock River under normal open flow conditions thus observing the change in water level, Froude number, and flow velocity. Results from this study help to point out the significance of ice jam occurrences and their effects on inline structures and future flooding concerns in the surrounding area.