The Pollution Control Department is preparing to inspect the wastewater being released by hotels and buildings in Pattaya after an outcry over photos shared online showing polluted water being released at Pattaya beach.

Pollution Control Department director-general Sunee Piyapanpong said her department will send officials to check hotels, condominiums, markets and other buildings from this month until July to make sure the wastewater they release adheres to environmental standards, especially regarding lipids.

Those who violate pollution laws face a 2,000 baht daily fine until they clean up their act, she said.

The photos were uploaded to the local Facebook Page "Pattaya Talk" on Friday and have drawn heavy criticism from residents of the resort town.

The photos show filthy water pouring out of a big drain into the sea. The poster also reported a foul smell.

This is not the first time such an incident has been reported.

When reporters surveyed the site on Friday, which is behind a pumping station in South Pattaya at the entrance to Walking Street, no water was coming out of the drain.

However, muddy sea water containing what appeared to be black residue was visible and tourists have been avoiding the area.

According to a local government source, wastewater from houses and business operations is diverted to several pumping stations before being funnelled to a wastewater treatment facility in Soi Wat Nong Yai in Bang Lamung district. The treated water is then released into the sea.

The facility is capable of handling 65,000-80,000 cubic metres on a daily basis, but the city's rapid growth means that it now releases up to 100,000 cu m of wastewater a day, the source said.

Several pumping stations and related equipment, which have been used for decades, are in a deteriorated state.

Following heavy rain, water has to be quickly pushed out of the drainage system to ward off flooding inland. Rainwater also causes the water in the system to have higher turbidity and Biochemical Oxygen Demand, which affects the purity of the wastewater.

The source conceded the images of black water flowing into the Pattaya sea have had an impact on tourism.

Work is underway to repair the drainage system while plans have been drawn up to construct a giant tunnel to drain rainwater out into the sea directly from Central Pattaya. A feasibility study of the issue is being conducted.