Numerical Simulation of Backwater Effects by a Downstream Dam using HEC-RAS: A case of SunKoshi- Marin Diversion Headworks, Nepal | ||
| Journal of Hydraulic and Water Engineering | ||
| دوره 1، شماره 2، فروردین 2024، صفحه 179-196 اصل مقاله (1.83 M) | ||
| نوع مقاله: Original Article | ||
| شناسه دیجیتال (DOI): 10.22044/jhwe.2024.14258.1036 | ||
| نویسنده | ||
| Mukesh Raj Kafle* | ||
| Department of Civil Engineering, Institute of Engineering, Pulchowk Campus, Nepal. | ||
| چکیده | ||
| This study evaluates the scenario of the flood backwater impacts on upstream of the Sunkoshi-Marin headworks. The design flood and hydrological analysis were carried out based on the stream flow data from 1968 to 2015 of Khurkot station. Probabilistic method was used to estimate design flood discharge and check flood values for 1000 and 10,000 years return periods frequency. Estimated design floods and check floods were 12,328 and 15,630 m3/s discharge respectively. Numerical simulation of backwater effects was carried out in three different cases- (i) headworks without affecting existing road (ii) headworks affecting existing road and (iii) headworks with inline structures using HEC-RAS. Water surface profiles estimation and backwater innundation map was generated for 1000 years return period flood. In the case (i) scenario simulated upstream and downstream water surface were 478.10 m and 477.22 m respectively. In the case (ii) those values were found 471.75m and 470.64 m respectively. Like wise, in the case (iii) scenario upstream and downstream water surface were found 475.79 m and 471.39 m respectively. The total inundated area including the river waterway was 340.89 ha with the extension up to 6 km in the Tamakoshi side and 8 km in the Sunkoshi side. The net inundation area excluding the river waterway was estimated 216.92 ha. The inundated areas lie within three rural municipalities, namely; Sunkoshi, Khadadevi and Manthali. Due to backwater innundation recommended length of the realigned section of the BP highway is about 1.3 kms. | ||
| کلیدواژهها | ||
| Backwater؛ design flood؛ HEC-RAS؛ headworks؛ rating curve | ||
| مراجع | ||
|
Beven, K.J., 2001. Rainfall-runoff modelling: the primer. Hydrological Sciences Journal, 46(6): 1002-1002.
Cordery, I., Pilgrim, D.H., 2000. The State of the Art of Flood Prediction.
Costabile, P., Macchione, F., Natale, L., Petaccia, G., 2015. Comparison of scenarios with and without bridges and analysis of backwater effect in 1-D and 2-D river flood modeling. Comput. Model. Eng. Sci, 109(2): 81-103.
CR, A., Thatikonda, S., 2020. Study on backwater effect due to Polavaram Dam Project under different return periods. Water, 12(2): 576.
Dasallas, L., Kim, Y., An, H., 2019. Case study of HEC-RAS 1D–2D coupling simulation: 2002 Baeksan flood event in Korea. Water, 11(10): 2048.
Emamgholizadeh, S., Bateni, S.M., Nielson, J.R., 2018. Evaluation of different strategies for management of reservoir sedimentation in semi-arid regions: a case study (Dez Reservoir). Lake and Reservoir Management, 34(3): 270-282.
ICOLD, 2017. International Commission on Large Dams; 2017. WORLD REGISTER OF DAMS/General Synthesis. Available online: http://www.icold-cigb.org/GB/world_register/general_synthesis.asp (accessed on 19 November ).
Liro, M., 2019. Dam reservoir backwater as a field-scale laboratory of human-induced changes in river biogeomorphology: A review focused on gravel-bed rivers. Science of the total environment, 651: 2899-2912.
Macchione, F., Viggiani, G., 2004. Simple modelling of dam failure in a natural river, Proceedings of the Institution of Civil Engineers-Water Management. Thomas Telford Ltd, pp. 53-60.
Maselli, V. et al., 2018. River morphodynamic evolution under dam-induced backwater: An example from the Po River (Italy). Journal of Sedimentary Research, 88(10): 1190-1204.
Patel, D.P., Ramirez, J.A., Srivastava, P.K., Bray, M., Han, D., 2017. Assessment of flood inundation mapping of Surat city by coupled 1D/2D hydrodynamic modeling: a case application of the new HEC-RAS 5. Natural Hazards, 89: 93-130.
Rahman, A., Weinmann, P.E., Hoang, T.M.T., Laurenson, E.M., 2002. Monte Carlo simulation of flood frequency curves from rainfall. Journal of Hydrology, 256(3-4): 196-210.
Reed, D., Robson, A., 1999. Flood estimation handbook, 3. Institute of Hydrology Wallingford.
SANRAL, 2013. Drainage Manual, 6th edn. The South African National Roads Agency SOC Ltd., Pretoria.
Scott, S.H., Sharp, J.A., Savant, G., Johnson, C., Ginter, D.M., 2012. Two dimensional hydrodynamic analysis of the Moose Creek floodway.
Sheng, B., 2014. Hydraulic Structure and Stream Vegetation Induced Backwater Effects on Wetland Flood Reduction, University of Wisconsin--Madison.
Smithers, J., 2012. Methods for design flood estimation in South Africa. Water SA, 38(4): 633-646.
Te Chow, V., 1959. Open channel hydraulics.
Teo, F.Y., 2010. Study of the hydrodynamic processes of rivers and floodplains with obstructions. Cardiff University (United Kingdom).
Van der Spuy, D., Rademeyer, P., 2016. Flood frequency estimation methods as applied in the Department of Water and Sanitation. Department of Water and Sanitation, Pretoria.
Volke, M.A., Johnson, W.C., Dixon, M.D., Scott, M.L., 2019. Emerging reservoir delta‐backwaters: biophysical dynamics and riparian biodiversity. Ecological Monographs, 89(3): e01363.
Yang, Y. et al., 2017. Influence of large reservoir operation on water-levels and flows in reaches below dam: Case study of the Three Gorges Reservoir. Scientific Reports, 7(1): 15640. | ||
|
آمار تعداد مشاهده مقاله: 207 تعداد دریافت فایل اصل مقاله: 250 |
||