Volume 5 Issue 1
Authors: Suresh Sharma; Aashish Shrestha; Colleen E. Mclean
Abstract: The impact of fresh water withdrawals for hydraulic fracturing has concerned water resource scientists and communities interested in sustainable water resource management. Specifically, low flow conditions in watersheds may be further reduced due to global climate change, as it has the potential to decrease streamflow. Since an earlier study found that the current rate of fracking had some impact on water availability, this study was conducted in order to ascertain whether or not the current fracking trend will have an impact in stream low flow in the future. This study was conducted on the Muskingum watershed in Eastern Ohio, which has been subjected to the rapid expansion of hydraulic fracking. The watershed model, Soil and Water Assessment Tool (SWAT), was used for watershed simulation using the climate output of Coupled Model Intercomparison Project Phase 5 (CMIP5). Precipitation and temperatures outputs from Max Planck Institute Earth System Model (MPI-ESM) were used to evaluate the variation in streamflow during the 21st century using three Representative Concentration Pathways (RCP) scenarios: RCP 2.6; RCP 4.5; and RCP 8.5. Three future periods, namely, 2035s (2021-2050), 2055s (2051-2070) and 2085s (2070-2099) were set against the baseline condition (1995-2009). Lowest flow was projected to increase across the watershed during 2035s period compared to the remaining 50 years period, under the highest forced climate scenario (RCP8.5). Similarly, mean flow also could be expected to decrease during 2035s in the eastern, north-western and south western portion of the watershed. Additionally, the streamflow was simulated using current fracking scenarios and 2035s climate output in order to assess the impact of water withdrawal for a continuous trend of current fracking rates. A modest effect on stream low flow was detected, when extreme scenario (RCP 8.5) was considered, especially in the headwater streams. While results indicate that 14 of 32 subbasins were affected, with maximum difference up to 55% in lowest 7 days minimum low flow (considered lowest value from each year), negligible impact was detected on mean monthly and annual streamflow. Analysis with RCP 2.6 and RCP 4.5 indicated that stream low flow would not be affected especially in higher order streams. Even though a localized effect of hydraulic fracking to reduce the environmental flow was detected; this research indicated that future climate change may not have additional adverse impacts if hydraulic fracking trends are stable.
Keywords: CMIP5; Climate Model; Hydrologic Analysis; MPI-ESM, SWAT; Low Flow; Drought
Authors: Danni Guo; Guy F. Midgley; Yoseph N. Araya; Jonathan Silvertown; Charles F. Musil
Abstract: The Restionaceae species of the Fynbos biome is part of the Cape Floristic Kingdom is threatened by urbanization, agricultural expansion, groundwater extraction, and climate change. Therefore, it is necessary to assess and monitor the Restionaceae species under the impact of climate change. South Africa is a semi-arid environment, and hydrological factors are the main variables in the determination of species niches. This study investigates the microclimate at Jonkershoek, and examines the impact of climate change to the plant species distribution, thus creating shifts in the hydrological niche. This study generates its own unique microclimate hydrological datasets for modelling species niche. The Restionaceae species and their hydrological niche at the Jonkershoek study area are assessed under future climate change scenario, at a microclimatic level. It provided evidence regarding the importance of the study to understanding the climate change impacts on hydrological niche and on species richness.
Keywords: Climate Change; Hydrological Niche; Restionaceae; Fynbos Biome; Microclimate; Jonkershoek; South Africa
Authors: Raj Mohan Singh; Prabhakar Shukla
Abstract: The groundwater resource is crucial for water supply, irrigation and urbanization. Accurate assessment of recharge and prediction of future groundwater levels in groundwater system is vital for water management in a particular area. Recharge, as an input to groundwater model, is usually some fraction of rainfall. However, recharge is affected by spatial and time varying events on the surface. The present study demonstrates use of Arc SWAT model for water surface simulation and the estimation of recharge rates. The recharge values estimated using Arc-SWAT model are inputs to Visual MODFLOW groundwater system simulation model, parametric sensitivity analysis with hydraulic conductivity value performed. Calibrated and validated model further employee for future groundwater levels predictions in potential groundwater management scenarios. Methodology employed in Sai-Gomti interfluve region in India.
Keywords: Groundwater Simulation; VISUAL MODFLOW; Sai-Gomti Interfluve; Uncertainty Analysis
Authors: Saeed Reza Khodashenas; Mohammad Tajbakhsh
Abstract: Nowadays along with the development of society, its impervious areas increase and therefore amount and volume of runoff accrue. Thus flood control in a pedestrian crossing, disorder of transport, contaminant flow and inundation in a residential area are the worry of designer and city manager. The primary goal of this research is simulation and evaluation of urban drainage system of East Eghbal basin which includes part of urban watershed in south and southeast of Mashhad city in Iran. The area of this basin is about 71 Km2. Due of complicacy in the simulation of an urban drainage system, after calibration and validation, MIKE SWMM used for rainfall - runoff simulation and hydraulic response evaluation of urban drainage system. By investigation in historical rains, 17 and 3 storms (include 11 consecutive storms) were selected for single and continues simulation respectively. The rainfall chosen in this study was 30 /4/1998. It had greater peak hydrograph on all sub-catchments. The amount, average intensity, and duration of this rainfall were 14.1 mm and 4.1 mm/hr and 206 min, respectively. The results of the simulation showed that 6 conduits of urban drainage system have difficulty for carrying of the storm water. Finally, based on topographic maps, flooded channels position and surveying the study area, 3 appropriate natural sites for storm infiltration basins were recognized. The uUrban drainage system was evaluated again by the presence of these basins and results showed a noticeable reduction in the flood.
Keywords: Infiltration Basin; GIS; MIKE SWMM; Urban Drainage System; Urban Flood