Reconstructing the historical water regime of the contributing basins to the Hawizeh marsh: Implications of water control structures

Prasad Daggupati; Raghavan Srinivasan; Yihun Taddele Dile; Deepa Verma

doi:10.1016/j.scitotenv.2016.12.029

Reconstructing the historical water regime of the contributing basins to the Hawizeh marsh: Implications of water control structures

Sci Total Environ. 2017 Feb 15:580:832-845. doi: 10.1016/j.scitotenv.2016.12.029. Epub 2016 Dec 21.

Authors

Prasad Daggupati¹, Raghavan Srinivasan², Yihun Taddele Dile², Deepa Verma³

Affiliations

¹ School of Engineering, University of Guelph, Guelph N1G 2W1, Canada. Electronic address: pdaggupa@uoguelph.ca.
² Spatial Science Laboratory, Ecosystem Science and Management Department, Texas A&M University, College Station, TX 77801, USA.
³ Water Shell Technology Centre Bangalore Shell India Marketing Private Limited, 3rd Floor, Campus B, RMZ Centennial, Bangalore 560048, India.

PMID: 28012653
DOI: 10.1016/j.scitotenv.2016.12.029

Abstract

The Hawizeh marsh, a unique wetland which is part of the Mesopotamian marshes, is recognized as a wetland of international importance. The marsh has been shrinking and there has been little research into its degradation. This study aims to reconstruct historical water regimes in the contributing basins (Tigris and Karkheh river Basins, TKRB) to investigate factors that have affected the wellbeing of the marsh. The Soil and Water Assessment Tool (SWAT) was used for this study. The model was calibrated and validated using nine river gauging stations. Results indicated that inflows to the marsh decreased by 65% and 80% in the '90s and 2000s, respectively, compared to the '80s. The reductions in streamflow were caused by decrease in precipitation and water abstraction. The annual precipitation decreased by 14% and 38% in the '90s and 2000s, respectively, compared to the '80s. Highest water abstraction was seen in Karkheh dam which caused a reduction of 45% in the annual streamflows. Average annual evaporative losses from Tharthar lake (2700km²) were very high (2260hm³ [cubic hectometer]). Although the Hawizeh marsh has been shrinking for the last three decades, recent satellite images (2013) have shown that the marsh has been reviving, mainly due to increased precipitation from 2011 to 2013. The revival of the marsh is promising; however, if the planned dams on TKRB are implemented, the future of the marsh remains uncertain. The sustainability of the Hawizeh marsh will require integrated water resources management among the riparian countries to rehabilitate and maintain this unique wetland.

Keywords: Hawizeh marsh; Mesopotamian marshlands; SWAT; Tigris basin; Water control structures.