Assessment of Sustainable Groundwater Extraction rate for Quetta city using MODFLOW

Abdul Ghani, Zulfiqar Ali Chaudary, Habib Rehman, Aftab Hussain Azhar, Muhammad Masood

Abstract


Quetta is the biggest population center in Baluchistan province. The city population entirely depends upon the groundwater beneath its aquifer. The increasing population of the city and unplanned use have depleted water table in the recent decades. The city population has increased from 0.26 million in 1975 to 1.452 million in 2014. This decline in the water table was first noticed by WAPDA in 1989 as 0.25 m/year due to over draft so they increased the observatory wells network. USGS groundwater flow model MODFLOW (MODFLOW Pro) was applied for the Quetta city to simulate the behavior of aquifer under stresses. The model was calibrated and validated for the available data.  The calibration results show that 20% of the total precipitation is ultimately going to the groundwater. The results show that the water table under Quetta city has declined at the average rate of 0.91 m/year since 1995 to 2014. The analysis shows that the abstraction rate for the city has increased from 32.25MGPD to 57.76 MGPD upon these 20 years. The Vermont Storm Water Management (VSWM) method of volume recharge was used to calculate the fraction of recharge that is retained by the imperviousness caused by the urbanization of the city. This fraction comes out 0.6 MGPD to 2.9 MGPD per year, depending upon the amount of precipitation and the amount of imperviousness for the same year. The water budget calculated by the model shows that the average recharge per year in this period is 37.04 MGD and the average abstraction from the aquifer is 84.20 MGD, so there is annual deficit of 47.11MGD is occurring at the city. The inflow through the boundaries is increasing with the passage of time due to fall of heads inside the model area, whereas the outflow through the boundaries is almost zero during our study period because of higher heads outside the model boundary. The model was then used to predict different future scenarios by giving the same average recharge rates and varying abstraction rates, in order to predict the future behavior of the aquifer<

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References


Abdul S. Khan. Shuhab D. Khan. Din M. Kakar. (2013).Land subsidence and declining water resources in Quetta Valley, Pakistan, Springer-Verlag Berlin Heidelberg. 2719-2727.

Irrigation and Power Department Report. (2007). Groundwater Monitoring Data, Pishin Lora Basin, Water Resources, Planning, Development & Monitoring Directorate, Govt of Balushistan Quetta.

Alam. K. (2010). Evaluation Of Aquifer System in Quetta Valley Through Geophysical Methods And Groundwater Flow Modeling. Institute of Geology, University of the Punjab Lahore.

Afzal . M. (2013). Groundwater Modeling of Lahore using MODFLOW. University of Engineering and Technology Lahore.

Al Fatlawi. A. N. (2011). The application of the mathematical model MODFLOW to simulate the behavior of Groundwater flow in Umm Er Radhuma unconfined aquifer. Euphrates Journal of Agriculture Science. 1-16.

A. Purjenaie, M. Moradi, A. Noruzi, A. Majidi (2012). Prediction of Aquifer Drawdown Using MODFLOW Mathematical Model (Case Study: Sarze Rezvan Plain, Iran). Geosciences 2012, 2(5): 112-116.

Berehanu1 B., T. Ayenew, T. Azagegn (2017) Challenges of Groundwater Flow Model Calibration Using MODFLOW in Ethiopia: With Particular Emphasis to the Upper Awash River Basin. Journal of Geoscience and Environment Protection, 5, 50-66.

Gumuła-Kaw A., A. Szymkiewicz, R. Angulo-Jaramillo et. Al (2017) Numerical simulation of infiltration and groundwater recharge using the Hydrus for Modflow package and the BEST model of soil hydraulic properties, Geophysical Research Abstracts Vol. 19, EGU-1514.

L.F. Konikow. Use of Numerical Models to Simulate Groundwater flow and Transport. US Geological Survey, Reston, Virginia, USA. 75-109.

C. P. Kumar. Groundwater flow models. National Institute of Hydrology, Roorkee 247667 (Uttaranchal).

William M. Alley et al. (1999). Sustainability of Groundwater Resources, U.S. Geological Survey Circular 1186. Denver, Colorado. 79.

Arlen W. Harbaugh, Edward R. Banta, Mary C. Hill and Michael G. McDonald. (2000). Modflow-2000, the U.S Geological Survey Modular Ground-Water Model-User Guide to Modularization Concepts and the Ground-Water Flow Process. U.S. Geological Survey, Reston, Virginia. 121.

C. P .Kumar. (2013). Numerical Modeling of Groundwater flow using MODFLOW. National Institute of Hydrology, Roorkee-247667, India. 86-92.

Processing MODFLOW. Tutorial of Processing MODFLOW Pro. Webtech.1-190.

Wen-Hsing Chiang and Wolfgang Kinzelbach. (1998). Tutorial of Processing MODFLOW, a simulation system for modeling Groundwater flow and Pollution.

Development Statistics of Baluchistan. (2013). Govt. of Balushistan Quetta.

Khan S., Khan A.S., Sultan M. and Mehmood K. 2010, Urbanization effects on water resources in Quetta valley Pakistan. 2010 GSA Denver Annual Meeting (31 October –3 November 2010), paper No. 254-3.

Frederick R. Steiner, Kent Butler (2012). Book of Planning and Urban Design Standards, American Planning Association,), PP 187-189.

James A. Roumasse. and Christopher A. Wada. (2010). Optimal and Sustainable Groundwater Extraction. Department of Economics, University of Hawaii at Mona, 2424 Maile Way, Honolulu, USA.






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