Estimating the Available Water in the Watershed using System Dynamics Hydrological Model (Case Study: Ilam Watershed)

Document Type : Research Article

Authors

1 School of Environment, College of Engineering, University of Tehran, Tehran, Iran

2 Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, USA

Abstract

Hydrological models provide water managers with the available amount of water in the watershed. In this paper, we firstly developed a system dynamics model to calculate the available amount of water in the watershed. Then, we defined two scenarios one of which is the development scenario describing how land use changes can affect water availability in the watershed. Next, we divided the watershed into upstream and downstream assuming that these two sub-watersheds have different physical features including soil type and land cover to find out how the available water changes. The system dynamics model includes three main components of the hydrologic processes: rainfall-runoff model, snow accumulation, and groundwater. The model calculates runoff at the outlet of a watershed and sub-watersheds with monthly time step. We applied the developed model to the Ilam watershed to demonstrate the capability of the model in estimating runoff volume and available water. We calibrated model coefficients based on minimizing the model’s error in estimating the out flow of the watershed. The error was measured using the Nash-Sutcliff efficiency coefficient, the Pierson correlation coefficient, and the standard error. Specific tests such as the dimensional analysis test, and extreme conditions test were utilized to assess the structural accuracy of the system dynamics model. Results showed the appropriate accordance of the model’s output with the observed data by a value of the Nash-Sutcliff coefficient (Ens) close to 1, the rather high data correlation coefficient (R), and also a low standard error for the model’s calibration and verification periods.

Keywords


Aboelata, M. (1998). Object-oriented modeling framework for water resources policy analysis.
Ahmad, S. and D. Prashar (2010). Evaluating municipal water conservation policies using a dynamic simulation model. Water Resources Management 24(13): 3371-3395.
Ahmad, S. and S. P. Simonovic (2000). System dynamics modeling of reservoir operations for flood management. Journal of Computing in Civil Engineering 14(3): 190-198.
Ahmad, S. and S. P. Simonovic (2004). Spatial system dynamics: new approach for simulation of water resources systems. Journal of Computing in Civil Engineering 18(4): 331-340.
Ahmad, S. and S. P. Simonovic (2006). An intelligent decision support system for management of floods. Water Resources Management 20(3): 391-410.
Boughton, W. (1989). A review of the USDA SCS curve number method. Soil Research 27(3): 511-523.
Carpenter, T. M. and K. P. Georgakakos (2006). Intercomparison of lumped versus distributed hydrologic model ensemble simulations on operational forecast scales. Journal of Hydrology 329(1): 174-185.
Deckers, D. L., M. J. Booij, T. H. Rientjes and M. S. Krol (2010). Catchment variability and parameter estimation in multi-objective regionalisation of a rainfall–runoff model. Water resources management 24(14): 3961-3985.
Elshorbagy, A. and L. Ormsbee (2006). Object-oriented modeling approach to surface water quality management. Environmental Modelling & Software 21(5): 689-698.
Feng, L. H. and C. Huang (2008). A risk assessment model of water shortage based on information diffusion technology and its application in analyzing carrying capacity of water resources. Water Resources Management 22(5): 621-633.
Ford, A. (2011).System dynamics models of environment, energy and climate change, in Extreme Environmental Events, edited, pp. 908-927, Springer.
Gastélum, J. R., J. B. Valdés and S. Stewart (2009). A decision support system to improve water resources management in the Conchos Basin. Water resources management 23(8): 1519-1548.
Gastélum, J. R., J. B. Valdés and S. Stewart (2010). A system dynamics model to evaluate temporary water transfers in the Mexican Conchos Basin. Water resources management 24(7): 1285-1311.
Ghashghaei, M., A. Bagheri and S. Morid (2013). Rainfall-runoff modeling in a watershed scale using an object oriented approach based on the concepts of system dynamics. Water resources management 27(15): 5119-5141.
Karamouz, M. and S. Araghinejad (2005). Advanced hydrology. Polytechnique University Publication, Tehran.
Madani, K. and M. A. Mariño (2009). "System dynamics analysis for managing Iran’s Zayandeh-Rud river basin." Water resources management 23(11): 2163-2187.
Mahab (2009). the long-term study of water quality of Ilam dam."
Mishra, S. and V. Singh (2002). SCS-CN method. Part 1: Derivation of SCS-CN-based models. Acta Geophysica Polonica 50(3): 457-477.
Mockus, V. (2010). Estimation of direct runoff from storm rainfall. National Engineering Handbook, Section 4– Hydrology.
Radzicki, M. J. (2009).System dynamics and its contribution to economics and economic modeling, in Complex Systems in Finance and Econometrics, edited, pp. 727-737, Springer.
Scharffenberg, W. A. and M. J. Fleming (2006). Hydrologic modeling system HEC-HMS: User's manual, US Army Corps of Engineers, Hydrologic Engineering Center.
Sterman, J. D. J. D. (2000). Business dynamics: systems thinking and modeling for a complex world.
Tisdale, T. S. (1996). Object-oriented analysis of south Florida hydrologic systems. Journal of Computing in Civil Engineering 10(4): 318-326.
Wang, J., J. M. Hassett and T. A. Endreny (2005). An object oriented approach to the description and simulation of watershed scale hydrologic processes. Computers & geosciences 31(4): 425-435.
Ward, R. (1968). Principles of Hydrology. Soil Science 106(4): 326.
Winz, I., G. Brierley and S. Trowsdale (2009). The use of system dynamics simulation in water resources management. Water resources management 23(7): 1301-1323.
Xi, X. and K. L. Poh (2013). Using system dynamics for sustainable water resources management in Singapore. Procedia Computer Science 16: 157-166.
Yang, C.-C., L.-C. Chang and C.-C. Ho (2008). Application of system dynamics with impact analysis to solve the problem of water shortages in Taiwan. Water resources management 22(11): 1561-1577.