The Meghalaya government is exploring the possibility of having additional roads in the Guwahati-Shillong route to minimise the vibration caused by vehicular traffic causing harm to the wall of the Umiam hyro-electric dam, the assembly was informed recently.
The Central Water Commission (CWC) recently expressed concern about the safety of the Umiam concrete dam saying the government may give priority to take up an alternative road, Chief Minister Conrad Sangma said.
Presently every vehicle coming from Guwahati side has to pass the 220 sq km scenic lake, a tourist attraction, and everyday thousands of vehicles ply by the dam, the first and the main hydro electric project in the state.
“We are looking at the possibility of having multiple entry-exit points in the state. The CWC has advised that traffic is to be diverted downstream of the Umiam dam,” Sangma said in his reply to the debate on governor’s address.
The issue of diversion of traffic on Umiam dam, located around 15 from Shillong, was taken up by the Meghalaya Energy Corporation (MeECL) with the state government, he said.
He said the MeECL had conducted a traffic vibration measurement study on the Umiam concrete dam in 2012, through the Central Water and Power Research Station (CWPRS), Pune.
“The findings indicated that the vibration levels are very low, insignificant and within safe limit,” he said quoting the report of the CWPRS.
However, the chief minister said, the CWPRC also suggested that it was not advisable to have continuous vibration due to heavy traffic on such an important structure and suggested diversion of traffic near the dam.
“This will also help in taking up maintenance works at the dam without any hindrance of traffic,” Sangma said.
The dam at the Umiam river came up in the early 1960s and the Meghalaya State Development Report in 2008 said it has a projected life span of 400 years with a gross storage capacity of 1,47,000 acre feet.
It also said the dead storage capacity has been silted up and the life of the reservoir would be reduced to about 65 years if the current rate of siltation is not checked.
Dead storage refers to water in a reservoir that cannot be drained by gravity through a dam’s outlet, spillway or power plant intake and can only be pumped out.
Stating that the matter was brought to the notice of the House around nine years ago when he was the Leader of Opposition, Sangma thanked Congress MLA George B Lyngdoh for bringing up the matter again.