CHAIYAPHUM: The Royal Irrigation Department (RID) is building the Lam Nam Chi reservoir in Ban Khwao district of this northeastern province to help alleviate the chronic water shortage in the kingdom's northeastern region.
Once completed, the 3.1-billion-baht reservoir will be able to hold some 70.21 million cubic metres (m³) of water -- enough to water some 75,000 rai of farmland and cover household consumption for 7,556 families in both Chaiyaphum and neighbouring Khon Kaen, the government said.
"The project has come a long way since it was initiated by the late King Rama IX in 1983. We plan to start pumping water from the reservoir by 2026," Sol Jindasa-nguan, director of the 13th Mega-Irrigation Project Development Office told the Bangkok Post during a press trip late last week.
He said the RID will pay some 200 million baht in compensation to expropriate some 9,082 rai of land which belongs to local villagers.
Mr Sol said the project can trace its roots back to 1971, when the RID proposed the construction of a mega-reservoir which it called the Yang Nadee reservoir.
However, the project was shelved as the late monarch thought too many villagers would be displaced, as in order to build the mega-reservoir -- which was designed to hold some 1.8 billion m³ of water -- some 100,000 rai of land would have to be expropriated.
In 1983, the late king suggested the project be divided and downsized in order to minimise its impact on local communities. But the proposal was shelved until 1989, when it was revived by the cabinet, albeit on a smaller scale.
Under the revived project, two dams were envisioned -- the Upper Chi reservoir and the Yang Nadee reservoir. The budget for the latter's construction was approved in 2018, and it was renamed Lam Nam Chi reservoir to celebrate the late monarch.
Mr Sol said authorities plan to build the Upper Chi reservoir by 2024.
Secretary-general of the Office of National Water Resources, Somkiat Prajamwong, said once completed, the Lam Nam Chi reservoir will be crucial to alleviating chronic water shortages in the country's Northeast.
"There are too few reservoirs in the Chi River basin, and it is very important to develop more of these reservoirs," he said.
The region's chronic water shortages are made worse by the lack of state irrigation networks.
Despite being known as Thailand's largest region, only 12.62% of the Northeast's total area is irrigated -- in other words, only about 8 million rai out of the region's 63 million rai of land aren't dependent on rainwater, according to the Office of National Water Resources.
Meanwhile, increased soil salinity has been detected in some 10.48 million rai of farmland in the region.
To address the region's chronic shortages, the RID and ONWR are also planning to create a network of water distribution system which will be fed by large reservoirs, such as the Lam Nam Chi and Upper Chi reservoirs, and smaller kaem ling or water retention ponds, which store water during the rainy season.
The water will be distributed to farmland during the dry season using a system of water pumps which would be installed along irrigation canals.