Local authorities have launched urgent probes into alleged encroachment on Klong Tha Dee as it flows through Khiriwong village in Nakhon Si Thammarat, hailed as one of the country's most pristine eco-tourism destinations.
The probes were ordered by provincial governor Siripat Patkul and Royal Forest Department (RFD) chief Atthapol Charoenchansa.
The investigations were prompted by a complaint aired in a video clip of an ugly concrete construction posted by a webpage called Chom Rom Strong-Jit Porpiang Tan Thudjarit (Strong Association-Sufficiency Mind against Corruption).
The complaint alleged vendors had poured cement along parts of the picturesque waterway and set up rest areas and stalls to cater to tourists.
It said that Khiriwong's ecology and environment must be maintained in its unspoiled state. The village draws tourists for the purity of its natural surroundings.
Mr Siripat said he was shocked by the report and instructed the provincial harbour office to investigate the matter urgently. If the law had been broken, the concrete will be removed and local businesses responsible for the encroachment would face swift legal action, he added.
The Lan Saka district chief and local administrative officials have joined the investigation.
Mr Atthapol said the RFD was conducting a parallel probe as Khlong Tha Dee comes under the Forestry Act. Any unauthorised action to change the physical integrity of the natural waterway amounts to an encroachment and is punishable by law. The department chief said the culprits would be ordered to demolish the construction within five days.
Netizens have deplored the concrete structure protruding into the water.
They said Khiriwong was suffering the same fate of other pristine natural attractions, where businesses have cut down trees and constructed tourist shops and accommodation.