Military officers have warned farmers to stop pumping water from Klong Makham Thao, or they will have their water pumps seized.
The officers, who were sent to inspect water drainage in Klong Makham Thao running through Chai Nat province, urged farmers to cooperate with authorities as they attempt to conserve water ahead of a forecast drought.
Authorities from the Regional Irrigation Office 12 in Chai Nat have released water from the irrigation system into the 104km Klong Makham Thao which stretches from Hankha district of Chai Nat to Don Chedi district in Suphan Buri to be used for tap water production.
Residents in tambon Ban Chian in Hankha district and other communities in Suphan Buri are facing a lack of drinking water.
The water cannot be pumped for farming until the Provincial Waterworks Authority's Don Chedi station in Suphan Buri has pumped water for the production of tap water for one day.
After that farmers will be allowed to use the water for farming.
But after five days of water release, the water flow has only extended 60km up the canal.
According to a survey by authorities, many pumping machines were used to drain water from the canal to feed plantations along the route.
An inspection found farmers had installed more than 10 water pumps close to Klong Makham Thao to drain water off to Klong 14 in tambon Nongsalai to be used for vegetable farming and feeding livestock.
Military officers said they had asked farmers for their cooperation in not draining the water in Klong Makham Thao, but many farmers did not listen.
As a result, the officers are prepared to exercise tough measures by seizing pumping machines if farmers still failed to follow regulations, a military source said.
They could reclaim their water pumps from authorities after Friday when the water releases end, he said.
The government expects a drought crisis to hit after April because water levels in the country's main dams are running low.