NEW DELHI, Dec 28 - The Centre today said the exact reasons for change in turbidity of the water of River Siang is not yet known and that it may be possibly due to landslide, earthquake or any other activity in the upstream region across the international border with China.
Replying to a Lok Sabha question, Minister of State for Water Resources Arjun Ram Meghwal said that during the recent visit of Foreign Minister of the People�s Republic of China to India on December 11, matters concerning trans-border rivers, including the recent reports about unusual change in the water quality of Siang River, were raised with the Chinese side. As a lower riparian State with considerable established user rights to the waters of the river, the Government of India has conveyed its views and concerns to the Chinese authorities, including at the highest levels of the Chinese government, and has urged them to ensure that the interest of downstream States are not harmed by any activity in the upstream areas.
Meghwal said change in colour of Siang water was noticed on November 10 at the Tuting Hydrological Observation (HO) site by the Central Water Commission (CWC) in Arunachal Pradesh. The cause of such change in colour of river water appears to be due to excess silt. Analysis of the water samples of Siang from Tuting and Passighat HO site of CWC shows that all observed water quality parameters are within permissible limits as per BIS 10500:2012 drinking water standard, except turbidity, said Meghwal.
In addition, results of water quality tests conducted by Public Health Engineering and Water Supply Department, Government of Arunachal Pradesh from samples of Pasighat shows turbidity and iron in excess of permissible limits. Beside this, physico-chemical analysis of water samples collected from Siang across Pasighat and Jonai, conducted by NERIWALM, shows higher concentration of aluminium and iron beyond acceptable and permissible limit for drinking, the minister said.
Change in water level was also observed by the CWC at Tuting and it was found that there was decrease in flow of water at Tuting from November 18 to November 19 (about 1.96 metres in level and approximate 50 per cent drop in water flow). Thereafter, the flow got restored to the previous level, the minister added.
Meanwhile, replying to another question about reports of China building a 1,000-km-long tunnel to divert Brahmaputra water, Minister of State for External Affairs General (retd) VK Singh said that the Chinese side has conveyed to us on several occasions that they are only undertaking run-of-the-river hydropower projects, which do not involve diversion of waters of the Brahmaputra. �We intend to remain engaged with China on the issue of trans-border rivers to safeguard our interest,� the minister said.
Various issues relating to trans-border rivers, including construction of hydro-power dams, were discussed with China under the ambit of an institutionalised Expert Level Mechanism, which was established in 2006. The government has also noted that the Chinese Ministry of Foreign Affairs has in a public statement rejected such media reports as untrue, General Singh added.
