KATHMANDU, MARCH 27
Melamchi Water Supply Development Board has made preparation to utilise the Melamchi tunnel by channelling water of the Melamchi River through alternative method after finding it impossible to remove dozens of metres high debris collected at the headwork of the tunnel due to flood and landslide in the monsoon last year.
The MWSD is planning to channel the water of Melamchi River directly towards the Ambathan audit tunnel from gate No 1.
For this, gate no 9, that leads outside the Ambathan audit into the river, will have to be closed. After closing the gate, water from gate no 1 can directly reach the centre at Sundarijal where the tunnel ends.
The MWSD had earlier said the tunnel was safe from the June 15 and July 30 flooding of 2021 which had wreaked havoc on the headworks of the multi-million dollar project that had finally come into operation 26 years after its inception.
As the main gate at the headworks was closed on time before the flooding, the tunnel remained safe.
Spokesperson of Melamchi Water Supply Development Board Rajendra Prasad Panta said workers were inspecting and cleaning the tunnel by entering through Ambathan audit. "If everything goes as per plan, we will let water of Melamchi River flow directly inside the tunnel from gate no 1 and divert it towards Sundarijal in Kathmandu valley," he said.
"We have found this alternative after realising that it was impossible to remove dozens of metres high debris spread over hundreds of square metres on the hilltop at the headworks anytime soon,"
Pant said. He however, stressed the current plan would only be temporary as channelling water directly inside the tunnel without headworks might cause permanent damage to the tunnel. "This system will be used until we are able to clear the headworks and start operating it again," Pant said.
The main infrastructure at the headworks is the 211-metre long diversion tunnel, which passes from the Melamchi River to gate no 1 of the 27.5-kilometremajor tunnel that extends to the valley.
As per the alternative plan, Kathmanduties are likely to get water by mid-July once again.
Rigorous work has been carried out to remove the debris at Melamchi Drinking Water Project that started in mid-January in a bid to deliver water to Kathmandu within the stipulated time.
Approximately 23 years after the inauguration of Melamchi Drinking Water Project, authorities had tested the water on 28 March 2021 and Kathmanduites had been able to get water supply to their homes for the first time.
Soon after, the project started supplying 170 million litres of water per day. But, the ill-fated project was struck by devastating flood in the Melamchi River on June 15. The flash flood eroded millions of tonnes of pebbles and sand, wreaking havoc on the low-lying Melamchi Bazaar.
A version of this article appears in the print on March 28, 2022, of The Himalayan Times.
