Wera, Fiona Annilow and Ling, Teck Yee and Lee, Nyanti and Sim, Siong Fong and Jongkar, Anak Grinang (2019) Effects of Opened and Closed Spillway Operations of a Large Tropical Hydroelectric Dam on the Water Quality of the Downstream River. Journal of Chemistry, 2019 (1). pp. 1-11. ISSN 2090-9071
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Abstract
Water quality downstream of a hydroelectric dam is potentially affected by dam operations and other land uses in the river basin. Previous short-distance studies below the large Bakun Dam indicated poorer water quality during closed spillway. However, the extent of the impact is still unknown. Such knowledge is essential for mitigating the impact of the dam. Thus, the objectives of this study were to determine the water quality up to a distance of 210 km under two spillway operations, namely, closed and opened spillways, and also to determine the changes in water quality from the predam condition. Physicochemical parameters were measured at 15 stations along the Rajang River. Results of this preliminary study indicated that there were significant differences in eight out of nine water quality parameters between opened and closed spillway operations with opened spillway showing better water quality. During closed spillway, as we approached the dam, there was an increasing acidity and a decreasing oxygen content. Furthermore, as the water flows downstream, the unhealthy DO level (<5 mg/L) extended up to 165 km and the linear model showed an increasing DO rate of 0.09 mg/L per km. With opened spillway, DO decreased exponentially from 9.74 mg/L towards the downstream direction to 7.67 mg/L. The increasing turbidity and TSS in the downstream direction indicate contributions from erosion due to other land uses. The river is polluted with organics as indicated by COD of Class IV or V with sources from the dam and the activities in the river basin. Compared to the predam condition, the regulated river is less turbid but warmer and higher in ammonia. Closed spillway led to lower DO and acidic water. However, opened spillway water pH and DO were similar to those in the predam condition. Thus, it is recommended that DO be consistently high enough for the health of sensitive aquatic organisms downstream.
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| Additional Information: | [1] L. Nyanti, T. Y. Ling, and J. Grinang, “Physio-chemical characteristics in the filling phase of Bakun Hydroelectric Reservoir, Sarawak, Malaysia”, International Journal of Applied Science and Technology, vol. 2, no. 6, pp. 92-101, 2012. [2] J. E. Girard, “Water Resources in Girdard, J. E (Ed.), “Principles of Environmental Chemistry,” Massachusetts: Jones and Bartlett Publishers, LCC, 2010. [3] T. Liang, S. Wang, H. Cao et al., “Estimation of ammonia nitrogen load from nonpoint sources in the Xitiao River catchment, China,” Journal of Environmental Sciences, vol. 20, no. 10, pp. 1195-1201, 2008. [4] R.T. Kingsford, “Ecological impacts of dams, water diversions and river management on floodplain wetlands in Australia,” Austral Ecology, vol. 25, pp 109-127, 2000. [5] T. Y. Ling, L. Nyanti, T. Muan et al., “Physicochemical parameters of Bakun reservoir in Belaga, Sarawak, Malaysia, 13 months after reaching full supply level,” Sains Malaysiana, vol. 45, no. 2, pp. 157–166, 2016. [6] T. Y. Ling, N. Gerunsin, C. L. Soo et al., “Seasonal changes and spatial variation in water quality of a large young tropical reservoir and its downstream river,” Journal of Chemistry, vol. 2017, Article ID 8153246, 16 pages, 2017. [7] R. Preece, Cold Water Pollution below Dams in New South Wales, Department of Infrastructure, Planning and Natural Resources, Sydney, Australia, 2004. [8] T. Y. Ling, C. L. Soo, T. E. Heng et al., “Physicochemical Characteristics of River Water Downstream of a Large Tropical Hydroelectric Dam,” Journal of Chemistry, vol. 2016, Article ID 7895234, 7 pages, 2016. [9] T. Y. Ling, C. L. Soo, T. P. Phan et al., “Assessment of the water quality of Batang Rajang at Pelagus Area, Sarawak, Malaysia,” Sains Malaysiana, vol. 46, no. 3, pp. 401-411, 2017. [10] Hach, Hach Water Analysis Handbook, Hach Company, Loveland, Colo, USA, 2015. [11] American Public Health Association, Standard Methods for the Examination of Water & Wastewater, 20th Ed. Washington D. C., American Public Health Association-American Water Work Association-Water Environment Federation, 1998. [12] S. P. Singh, J. G. Sharma, T. Ahmad et al., “Effect of water temperature on the physiological responses of Asian Catfish Clarias batrachus (Linnaeus 1758),” Asian Fisheries Science, vol. 26, no. 1, pp. 26-38, 2013. [13] M. Kędra and L. Wiejaczka, “Climatic and dam-induced impacts on river water temperature: Assessment and management implications,” Science of The Total Environment, vol. 1, no. 1, pp. 1-10, 2017. [14] Department of Environment. Malaysia Environmental Quality Report 2015. Kuala Lumpur, Department of Environment, 2016. [15] T. P. Sagar, S. Singh, V. Singh et al., “Effect of water pH on growth and production of fish in the Coka Dam Papara Distt. Satna (M.P.)”, International Journal of Pharmacy & Life Sciences, vol. 3, no. 9, pp. 1979-1981, 2012. [16] K. K. Al-Ahmady, “Analysis of oxygen transfer performance on sub-surface aeration systems,” International Journal of Environmental Research and Public Health, vol. 3, no. 3, pp 301-308, 2006. [17] A. Bhatnagar and P. Devi, “Water quality guidelines for the management of pond fish culture,” International Journal of Environmental Science, vol. 3, no. 6, pp. 1980-2009, 2013. [18] R. Schouten, “Effects of dams on downstream reservoir fisheries, case of Nam Ngum.” Mekong Fisheries Network Newsletter, ISSN 0859-290X, vol. 4, no. 2, Dec 1998. [19] T. Y. Ling, C. L. Soo, J Sivalingam et al., “Assessment of the water and sediment quality of tropical forest streams in upper reaches of the Baleh River, Sarawak, Malaysia, subjected to logging activities,” Journal of Chemistry, vol. 2016, Article ID 8503931, 13 pages, 2016. [20] A. S. Tawan, Water Quality and Sediment Characteristics of Rajang River at the Pelagus Area and its Tributaries. Unpublished Master’s thesis. Universiti Malaysia Sarawak, Malaysia, 2018. [21] F. Al-Badaii, M. Shuhaimi-Othman and M. B. Gasim, “Water quality assessment of the Semenyih River, Selangor, Malaysia,” Journal of Chemistry, vol. 2013, Article ID 871056, 10 pages, 2013. [22] Y. Teng, J. Yang, R. Zuo et al., “Impact of urbanization and industrialization upon surface water quality: A pilot study of Panzhihua mining town,” Journal of Earth Science, vol. 22, no. 5, pp. 658-668, 2011 [23] T. Y. Ling, K. Apun, and S. R. Zainuddin, “Performance of a pilot-scale biofilters and constructed wetland with ornamental plants in greywater treatment,” World Applied Sciences Journal vol. 6, no. 11, pp. 1555-1562, 2009. [24] S. Mohd-Asharuddin, N. Zayadi, W. Rasit et al., “Water quality characteristics of Sembrong Dam Reservoir, Johor, Malaysia,” IOP Conference Series: Materials Science and Engineering, vol. 136, no. 1, 2016. [25] W. A. Amneera, N. Wahidatul, A. Zainon et al., “Water quality index of Perlis River, Malaysia,” International Journal of Civil & Environmental Engineering IJCEE-IJENS, vol. 13, no . 2, pp. 1–6, 2013 [26] A. A. Mamun and Z. Zainudin, “Sustainable River Water Quality Management in Malaysia,” IIUM Engineering Journal, vol. 14, no. 1, pp. 29-42, 2013. [27] T. Y. Ling, N. Gerunsin, C. L. Soo et al., “Nutrient level of a young tropical hydroelectric dam reservoir in Sarawak, Malaysia,” Borneo Journal of Resource Science and Technology, vol. 8, no. 1, pp. 14-22, 2018. [28] B. K. Galunder, and M. Kolar, “Chemical analysis and the River Mura water Quality,” International Journal of Sanitary Engineering Research, vol. 4, no. 2, pp. 4-17, 2010. [29] C. Bosman, “The hidden dragon: nitrate pollution from open-pit mines - A case study from the Limpopo Province, South Africa,” International Mine Water Conference, vol. 1, no. 1, pp. pp. 849-857, 2018. [30] M. Mohamed, G. Ismail and A. Memon, Bio-physical Impacts of Large dams in the Humid Tropics: The Bakun Project in Sarawak, Malaysia. EPMRC Publications, New Zealand, 1997. |
| Uncontrolled Keywords: | Hydroelectric dams, Bakun Dam, water quality, closed spillway, downstream river, unimas, university, universiti, Borneo, Malaysia, Sarawak, Kuching, Samarahan, ipta, education, research, Universiti Malaysia Sarawak. |
| Subjects: | Q Science > QD Chemistry |
| Divisions: | Academic Faculties, Institutes and Centres > Faculty of Resource Science and Technology Faculties, Institutes, Centres > Faculty of Resource Science and Technology |
| Depositing User: | Yee |
| Date Deposited: | 30 Jan 2019 07:08 |
| Last Modified: | 28 Apr 2021 12:05 |
| URI: | http://ir.unimas.my/id/eprint/23231 |
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