Some Western Bay residents have reported stomach pains, rashes and puffy eyes after problems with their water supply.
On Tuesday, the Western Bay of Plenty District Council confirmed a high pH level in its water supply feeding about 300 homes in the Pongakawa and Paengaroa areas from Monday. Residents were advised not to drink or use the water.
The pH levels in the water supply were restored to recommended levels yesterday.
Read more: Water issues now resolved
The latest incident followed an event in March when a malfunction at a water plant resulted in a warning to Pukehina Beach residents not to drink or use water. The council had received two complaints, including a report of a woman suffering a rash after taking a shower.
In response to Bay of Plenty Times queries about whether any residents had suffered similar effects from the water this time, the council issued a media release saying it received 20 calls from people near Wilson Rd South and Arawa Rd.
"A handful of residents reported skin reactions such as rashes and feeling burning sensations, while others reported having sore stomachs and puffy eyes or that the water felt slimy," the statement said.
"Monday evening's issue is thought to have been caused by a section of water main line that had not been active for a period of time being brought back on line without adequate flushing.
"This led to a body of water with higher than normal pH entering the main system affecting some properties in the Paengaroa and Pongakawa areas."
The council stated that staff and contractors working overnight Monday and through Tuesday to flush the water and test the system.
"They also visited properties to manually flush individual water supplies, advise residents and provide bottled water."
Medical Officer of Health Dr Neil de Wet said a high pH level meant the water was more alkaline than it should be and the main concern about this was that it could cause skin irritation in some people.
Toi Te Ora Public Health has liaised with local medical practices in the area and checked with hospital emergency departments and had been made aware of one person who had symptoms of skin irritation, Dr de Wet said.