Quality assessment of Tsurang River water affected by coal mining along the Tsurangkong Range, Nagaland, India

Abstract

Tsurang, a major river in the Mokokchung district of Nagaland, northeast India, shares great aspects of traditional importance for the Ao Naga tribes and is a part of natural commodity providing water to the agrarian community for irrigation and livestock rearing. However, various environment detrimental activities are practiced along the course of the riverbank, particularly coal mining and agriculture. The present study was conducted to examine the seasonal water quality index (WQI) of the Tsurang river from three selected sampling stations. Overall, the water quality status was rated as “Good” in winter and spring while “Poor” in summer and autumn. In all the seasons, downstream (S3) located at the human settlement area presented higher WQI values compared to upstream (S1) and midstream (S2). The parameters such as turbidity, DO and BOD played a central role in affecting the WQI; although, no such significant roles in case of nutrient elements were observed in affecting the water quality. The WQI revealed that Tsurang river water is deteriorated due to coal mining and other anthropogenic activities practiced along the stretch of the river and the water needs to be pretreated before consumption. Therefore, proper management strategies and conservation efforts should be enforced and regulated by policymakers to protect the river from further contamination.

Impact of Coal Mining on the Tzuong River System of Mokokchung, Nagaland

“…Similar results were reported by Semy and Singh (2019, 2021a, 2021b). [27][28][29] The concentration of iron ranges from 0.27-4.77 mg/L. The sample collected at site C8 has the highest concentration of iron at 4.77 mg/L.…”

“…This ensures that the data sourced from various parameters of water is reduced into a value that is logical and simplified. 29,[35][36][37] The method, Weighted Arithmetic Index (WAI) 38 was employed to determine WQI following:…”

“…Extensive coal mining in and around the Changkikong range of Mokokchung has irreparably changed the landscape and highly degraded the water bodies. The deterioration in the quality of water and soil because of activities related to coal mining in the Mokokchung region of Nagaland was stressed by workers such as Tiakaba (2016), 26 Semy and Singh (2019, 2021a, 2021b), [27][28][29] and Semy et al, (2022). 30 The purpose of the study is to determine the ramification of coal mining on the Tzuong River and its tributaries.…”

Socio-Ecological Impact of Coal Mining: A Study in Molungkimong Village, Nagaland

“…Tzurang is one of the major tributary rivers found in Molungkimong village and is a part of a natural commodity providing water to the community for irrigation and livestock rearing. However, the practice of coal mining in the area has critically affected the Tzurang river and deteriorated the water quality (Semy & Singh, 2021). The abundant aquatic life started depleting because of excessive dumping of coal waste in the river.…”

Evaluation of water quality of Mundeswari River in eastern India: a water quality index (WQI) based approach

“…Water quality index (WQI) is the most efficient mathematical tool used to assess water quality by converting large complex datasets of many water quality characteristics into straightforward numeric rating scales (Matta et al, 2020). WQI converts the raw data of a variety of quality parameters into single-value information and expresses the data in a "simplified and logi-cal form" (Gitau et al, 2016;Semy and Singh, 2021). The role of WQI is very significant for assessing river water quality as it gives a comprehensive interpretation of the river water quality and its appropriateness for various uses, such as drinking, irrigation, etc.…”