The effect of mineral hot water springs on the quality of the river based on toxicity indicators (case study: the effect of Ghaynarjeh Nir hot spring on the Balkhlichai river)

Balkhli River, which flows into Yamchi Dam, is the main supplier of drinking water in Ardabil City. This research aims to investigate the effect of the Ghaynarjeh Spring on Balkhli River based on surface waters quality indices.

First, monthly monitoring and analysis of Ghaynarjeh spa spring (station 1), river before acceptance and after acceptance of spring water (stations 2 and 3) was done for one year. Despite the low discharge of the spring compared to the river, The concentration of some cations and anions in the river increased greatly. In this article, by determining IRWQISC as the surface water quality index of Iran and NSFWQI as an international index, the water quality for three stations was determined.

The results showed that the quality of the river water after entering the spring water was degraded; In other words, the IRWQISC index of the quality of the river's water quality decreased from relatively good to average. Due to the presence of about 2,000 ppb of arsenic, about 7,000 ppb of iron and about 2,500 ppb of manganese in Ghaynarjeh Spring of Nir City, Therefore, the IRWQIST index was also considered in this research. As a result of entering the spring into the river, the river's toxicity index dropped two levels from a relatively good condition to a relatively bad one.

Considering the high impact of ghaynarjeh spring on the quality of Balkhli Chai River from the perspective of IRWQISC and especially IRWQIST indicators and considering the importance of Balkhli Chai River in supplying drinking water in Ardabil city, the necessity of purifying the spring water before entering the Balkhli Chai River is quite evident.