Sedimentation and its Challenges for Operation and Maintenance of Hydraulic Structures using SHARC Software- A Case Study of Eastern Intake in Dez Diversion Dam in Iran

Analytical investigation of the sedimentation processes in the river engineering and hydraulic structures is of vital importance as this can affect water supply for the cultivating lands in the command area. The reason being that gradual sediment formation behind the reservoir can reduce the nominal capacity of these dams. The aim of the present paper is to analytically investigate sedimentation process along the river course and behind the storage reservoirs in general and the Eastern Intake of the Dez Diversion weir in particular using the SHARC software. Results of the model indicated the water level at 115.97m whereas the real time measurement from the river cross section was 115.98 m which suggests a significantly close relation between them. The average transported sediment load in the river was measured at 0.25mm , from which it can be concluded that nearly 100% of the suspended loads in river are moving which suggests no sediment settling but indicates that almost all sediment loads enters into the intake. It was further showed the average sediment diameter entering the intake to be 0.293 mm which in turn suggests that about 85% of suspended sediments in the river entre the intake. Comparison of the results from the SHARC model with those obtained form the SSIIM software suggests quite similar outputs but distinguishing the SHARC model as more appropriate for the analysis of simpler problems than other model.

Authors:

• M.R. Mansoujian
• N. Hedayat
• M. Mashal
• H
• Kiamanesh

Keywords:

• SHARC
• Eastern Intake
• Dez Diversion Weir.

References:

[1] N. Hedayat, "Improving The Performance Of Water Delivery In The
Dez & Moghan Irrigation Schemes In Iran," PhD Thesis, Cranfield
University, UK 2005.
[2] Operation and Maintenance of the North Khuzestan Irrigation and
Drainage Company (2009). KWAPA, Dezful, Iran.
[3] Department for International Development."Sediment and Hydraulic
Analysis for Rehabilitation of Canals, "Software Manual, H.R
Wallingford, 2001.
[4] A. R. Abshoori, "Investigating the sedimentation process in settling
basin in irrigation network of the Imam Khomeini agro-complex, " M.Sc
Dissertation, Chamran University, Iran. , 2006, pp.14-30 , 104-107
[5] A. Chadwick, J. Morfett, "Hydraulics in civil environmental
engineering, 3rd. translated by M. Mashal, Tehran University, 2008, pp.
141-147
[6] M. Shafaaee Bejestan, "Sedimentation Hydraulics," first Edition,
University Of Chamran, Iran, 1994, pp. 250-253
[7] L. Najafi, "Investigating the challenges of the water intake in Diversion
weirs and means of overcoming them, Case study in Dez Diversion Dam
in Dezful," Iran. M.Sc Dissertation, Khajeh Nasiradin University,
Tehran, Iran.Toosi, 2005.
[8] S. Ashkarian, H. Kiamanesh, N. Hedayat, "Simulation of the flow
pattern using Flow 3D software, a case study in the Dez diversion Weir
in Dezful, " Iran. Proceedings: National Conference in water, soil, plant
and mechanization, Islamic Azad University, Dezful, Iran, 2010.
[9] H. Shirin, N. Hedayat, H. Kiamanesh, "Analytical investigation of the
sedimentation process and their underlying cause, a case study in the
Dez Diversion Weir in Dezful, " Iran, Proceedings: National Conference
in water, soil, plant and mechanization, Islamic Azad University, Dezful,
Iran, 2010.
[10] M. R. Mansoujian,. "Critical investigation of the sedimentation
processes in the water intakes using the SHARC software, A case study
of the Eastern Intake structure in Dezful, " M.Sc dissertation, I.azad
University, Dezful, Iran, 2008.