The stretch of brown water ran from the Pak Bang Canal at the southern end of the beach to offshore from the Police Box at the end of Bangla Rd.
“We collected water samples after we were informed of the brown water returning yesterday,” said Suphasit Boonpeinphol of the Phuket Marine Biological Centre (PMBC).
“It is similar to last time,” he added. “The cause might be from a plankton bloom, as the standard tests we did on the samples collected show the water quality is normal.
“Plankton (chaetocero) blooms are caused by nutrients. They are spurred on by days of bright sunshine.”
However, Mr Suphasit said that more extensive tests would be conducted on the water samples.
“But we will not know the results of these tests until after Songkran,” he added.
Officials earlier this month assured that a similar brown water “bloom” was not the result of wastewater dumped into Patong Bay. Instead, they said it was a plankton bloom. (See story here.)
Additional reporting by Darawan Naknakhon.