In this study, the physical, chemical and biological characteristics of the surface water of various inland lakes situated in Coimbatore have been analysed. The physico-chemical and biological parameters, such as pH, TDS, electrical conductivity, total hardness, chlorides, sulphates, sodium, potassium, BOD, COD, total alkalinity and E. coli concentration were analysed. The water quality of Selvampathy lake has drastically reduced as TDS, total hardness, BOD and COD values are beyond the permissible limit for this lake. This is due to discharge of industrial effluents and dumping of solid wastes. The chloride concentration of all the lakes has increased considerably. The low sulphate concentration in all these lakes indicates that there is no agricultural runoff and animal wastes being dumped into these lakes. The BOD concentration of Ukkadam lake has increased by an order of magnitude within the past three years. Ukkadam and Selvachintamani lake has faecal contamination as the E. coli concentration is beyond the permissible limit. The degradation of the quality of these lakes poses a major threat for the aquatic biota, public health and ground water quality.

中文翻译：

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印度泰米尔纳德邦哥印拜陀内陆湖水质状况评估

在这项研究中，分析了位于哥印拜陀的各种内陆湖泊的地表水的物理，化学和生物学特性。理化和生物学参数，例如pH，TDS，电导率，总硬度，氯化物，硫酸盐，钠，钾，BOD，COD，总碱度和大肠杆菌浓度进行了分析。随着TDS，总硬度，BOD和COD值超出该湖的允许极限，Selvampathy湖的水质已大大降低。这是由于工业废水的排放和固体废物的倾倒。所有湖泊的氯化物浓度已大大增加。所有这些湖泊中的硫酸盐浓度都很低，这表明没有农业径流和动物粪便倒入这些湖泊。在过去三年中，Ukkadam湖的BOD浓度增加了一个数量级。Ukkadam和Selvachintamani湖由于大肠杆菌而受到粪便污染浓度超出允许的范围。这些湖泊的质量下降对水生生物群，公共卫生和地下水质量构成了重大威胁。