Publications

Climate change is projected to have significant impacts on patterns of weather variables all around the world. To study the impacts of climate change on rainfall, different global climate models (GCMs) and climate scenarios are used to build projections for probable future patterns of rainfall. Using the rainfall projections, the change in runoff peaks and volumes can be projected. In this paper, a climate change impact study is presentedto investigate the effect of future uncertain rainfall patterns on urban runoff in the Bronx River watershed in New York City, USA. For the purpose of this study, the U.S. Environmental Protection Agency Storm Water Management Model (EPA SWMM) is developed for the study watershed and driven by precipitation data from the IPCC CMIP5 (Coupled Model Intercomparison Project Phase 5). Three scenarios of maximum, average, and minimum rainfall are defined to cover all the probable thresholds of future rainfall for a time horizon of 30 years. A change factor-based methodology is developed and employed to temporally disaggregate daily rainfall to an hourly basis. Flow-duration curves for climate change scenarios and the simulated runoff using the historical rainfall are compared. The results show climate change impacts to increase flow exceedances, runoff volume, and annual maxima peak discharges.

DigitalCommons@USU - Spring Runoff Conference: Developing a new comprehensive vulnerability assessment method to evaluate the impact of climate change on water supply system performance Home Search Browse Collections My Account About DC Network Digital Commons Network™ Skip to main content Spring Runoff Conference My Account FAQ About Home < Previous Event Next Event > Home > Conferences and Events > RUNOFF > Forum for Interdisciplinary Sharing of Ideas on Water-Related Issues > 2014ABSTRACTS > 40 2014 Abstracts Event Title Developing a new comprehensive vulnerability assessment method to evaluate the impact of climate change on water supply system performance Presenter Information Erfan Goharian Location Eccles Conference Center Event Website http://water.usu.edu Start Date 4-2-2014 3:50 PM End Date 4-2-2014 4:00 PM Description AWRA Student Paper …

Climate change can alter rainfall runoff regimes in urban areas by changing rainfall patterns and consequently increasing runoff peaks and volumes. Low impact developments (LIDs) and green infrastructure techniques are strategies that can be employed to control and decrease stormwater runoff in urban areas. In this study the potential for green infrastructure implementation to mitigate future climate change impacts on wet weather flow in the case study of the Bronx River watershed in New York City, USA, is analyzed. For this aim, the U.S. Environmental Protection Agency Storm Water Management Model (EPA SWMM) is created for the study watershed and driven by precipitation data from the IPCC CMIP5, which are temporally disaggregated using a new change factor methodology. In the following, the SWMM low-impact development (LID) controls component is used to investigate the effect of LIDs on runoff change. Flow-duration curves for historical and projected runoff by climate change are then compared. A scenario of rainwater harvesting and bioretention is found to provide a reduction in flow volume and peak. In conclusion, the climate change impacts are expected to produce more runoff and increase runoff peak in the region, and green infrastructure will provide mitigation benefits.

Destruction caused by recent hurricanes on natural and built environment along New York City coastlines emphasize the significance of delineating coastal floodplain and mapping the potential area of inundation followed by coastal floods. Floodplain delineation and appropriate planning in these areas could help mitigate some flood damage. In this study, a geographic information system (GIS) based method is proposed and applied for floodplain delineation in the coastal part of the Bronx River watershed, Bronx, New York City. Extreme water level in recurrence intervals of 2, 5, 10, 25, 50, and 100 years is determined by frequency analysis of the extreme sea levels in the region provided by NOAA (National Oceanic and Atmospheric Administration). To determine coastal floodplain followed by increasing water level, HEC-RAS model is used. The GIS (geographic information system) capabilities are used for illustration of inundated regions. The results of the study show that the extent of floodplain perpendicular to the river direction can be increased by up to 500 ft regarding the water level with 100-year return period. Taking into account these results in determining land use of the floodplain beside the river enables mitigation of the damages associated with coastal flooding caused by extreme water levels.