Krystal Gibbons was running a bath for her 5-year-old triplets on Sunday evening when the boys noticed something odd.
"They just kept asking 'why is the water green'," the Bayfair woman said. "I thought maybe they tipped something in."
Across town at Welcome Bay, Sez Lawrence had similar thoughts about her own bathwater.
"I assumed the kids had left a toy or something in there which had given it a green tinge," she said.
These two women were not alone.
By Monday morning, social media was abuzz with dozens of reports of tainted water in suburbs including Mount Maunganui, Pyes Pa, and Papamoa.
The reports prompted safety fears, with some people expressing concern that Tauranga's tap water had somehow been rendered dangerous to drink or even to bathe in.
One person described the water as "gross" and said she did not want to drink it, while another said that the water tasted strange.
On Facebook, Naomi Hall posted a photo of green-tinged water that she snapped after running bathwater in her home at Maunganui Rd, Mount Maunganui.
This prompted comments from residents reporting colours ranging from yellow to brown.
Karlie Morrow of Mount Maunganui said her water had been a browny-orange colour last week after rain, but Sunday was the first time she'd seen a green colour.
"I noticed it when we ran the bath," she said. "I guess it was the large volume with the white bath."
Although most people only saw colours when looking through large quantities of water, one person reported noticing a taint when filling a relatively shallow dog-bowl.
I assumed the kids had left a toy or something in there which had given it a green tinge.
Several people proposed theories about what might be causing the problem. These included chlorine reacting with metal pipes, filtration problems, a dead person in the pipes and "getting ready for St Patrick's Day".
Tauranga City Council moved quickly to quell the concerns, stating late on Sunday night that the water was safe to drink.
"The heavy rain has washed lots of leaves and debris into the water supply streams," the council said in a statement. "The water has been processed to remove bacteria and make sure it's safe to drink, but some traces of colour remain.
"Kind of like tea."
The council said the colour would remain until streams settled down.
The coloured water would mostly affect people on the Joyce Rd supply, the council said. This included Pyes Pa, Lakes, Welcome Bay, Maungatapu, Mount Maunganui and Papamoa.
Waihi and Paeroa have also been having problems with water supplies after the weekend's heavy rain.
Hauraki District Council yesterday asked residents from both towns to minimise their water usage until at least Wednesday.
Council communications officer Paula Trubshaw said debris and silt had increased the amount of time needed to process water. Updates would be posted on the council's Facebook page.