KATHMANDU, April 12 (Xinhua) -- The excavation of the 26-km longest tunnel in Nepal, that ensures improved water services for residents of Kathmandu, has been completed on Thursday.

The tunnel will be fully operational in a few months and carry water from the Melamchi River to the Kathmandu Valley for supply by the Kathmandu Upatyaka Khanepani Limited (KUKL).

The breakthrough ceremony was held in Melamchi on Thursday amid the presence of Vice President of Nepal Nanda Bahadur Pun, Minister for Drinking Water Bina Magar and Asian Development Bank's (ADB) Director General for South Asia Hun Kim.

According to a statement issued by ADB, which is a part of a project, the Melamchi Water Supply Project will benefit an estimated 1.3 million urban inhabitants with more reliable water supply and higher quality water.

"The completion of the excavation marks a very important milestone in the project's history and is indeed a giant leap forward for the project, one that will soon help alleviate the water stress experienced by the inhabitants of the Kathmandu Valley," Hun Kim said in the statement.

As per ADB, the current water supplied by KUKL is about 100 million liters per day (mld) on average, with about 40 percent of this estimated to be lost due to leakages. An additional 170 mld of water will be available by the end of 2018 for distribution to KUKL customers.

It has been mentioned that water will be supplied daily for at least 2-4 hours to KUKL customers once the new system is put into operation.

"ADB has provided a total of 45 million U.S. dollars in loans for the 355.4 million U.S. dollars Melamchi Water Supply Project and has been working since 2000 with the government to build the tunnel as well as 29 km of access roads," the statement reads.

The Nepali government is planning to complete all finishing works and testing of the tunnel by early July, with testing of the new transmission and distribution system in the Kathmandu Valley to start from August.