Integrated Approach for the Assessment and Development of Groundwater Resources in Arid Lands: Applications in the Quetta Valley, Pakistan
Loading...
Date
2010-12
Authors
Sagin, Jay
Journal Title
Journal ISSN
Volume Title
Publisher
Nazarbayev University School of Engineering and Digital Sciences
Abstract
The lack of adequate field measurements (e.g., precipitation and stream flow) and
difficulty in obtaining them often hampers the construction and calibration of rainfallrunoff
models over many of the world’s watersheds, leaving key elements of the
hydrologic cycle unconstrained. We adopted methodologies that rely heavily on readily
available remote sensing datasets as viable alternatives and useful tools for assessing,
managing, and modeling the water resources of such remote and inadequately gauged
regions. The Soil and Water Assessment Tool was selected for continuous (1998–2005)
rainfall-runoff modeling of the northeast part of the Pishin Lora basin (NEPL), a
politically unstable area that lacks adequate rain gauge and stream flow data. To account
for the paucity of rain gauge and stream flow gauge data, input to the model included
satellite-based Tropical Rainfall Measuring Mission TRMM precipitation data. Modeled
runoff was calibrated against satellite-based observations including: (1) monthly
estimates of the water volumes impounded by the Khushdil Khan (latitude 30° 40'N,
longitude 67° 40'E) and the Kara Lora (latitude 30° 34'N, longitude 66° 52'E) reservoirs,
and (2) inferred wet versus dry conditions in streams across the NEPL throughout this
period. Calibrations were also conducted against observed flow reported from the Burj
Aziz Khan station at the NEPL outlet (latitude 30°20'N; longitude 66°35'E). Model
simulations indicate that (1) average annual precipitation (1998–2005), surface runoff,
and net recharge are 1,300 × 106 m3, 148 × 106 m3, and 361 × 106 m3, respectively; (2)
within the NEPL watershed, precipitation and runoff are high for the northeast
(precipitation: 194 mm/year; runoff: 38 × 106 m3/year) and northwest (134 mm/year; 26 ×
106 m3/y) basins compared to the southern basin (124 mm/year; 8 × 106 m3/year); and (3)
construction of delay action dams in the northeast and northwest basins of the NEPL
could increase recharge from 361 × 106 m3/year up to 432 × 106 m3/year and achieve
sustainable extraction. The adopted methodologies are not a substitute for traditional
approaches that require extensive field datasets, but they could provide first-order
estimates for rainfall, runoff, and recharge in the arid and semi-arid parts of the world
that are inaccessible and/or lack adequate coverage with stream flow and precipitation
data.
Description
Keywords
Groundwater Resources
Citation
Jay Sagin; 2010; Integrated Approach for the Assessment and Development of Groundwater Resources in Arid Lands: Applications in the Quetta Valley, Pakistan