The thefts took place yesterday and follow a six-week drought.
The shortage became dire this week when residents in Kaiwaka and Mangawhai, whose populations swell in summer, were informed they could not replenish their water tanks until the end of the month.
Hibiscus Coasts residents were also facing delays and water carriers have been turned away from WaterCare's Wellsford and Snells Beach filling stations because connected residents were given priority ahead of those on tank water.
On Monday long queues were forming at Mangawhai's only laundromat and bottles of water were flying out the door of its two general stores as desperate residents tried to secure supplies.
Mander said his own reserves were getting low and he has been praying for rain.
"We're running low and we have a bakery in store so we need to use water. We're extremely low and on the verge [of running out].
"Some people might think that businesses in the area have their own bores but we certainly don't."
Mander and his young family were having to shower at a farmer friend's house, which has a bore, and borrow water for daily requirements.
He said he had managed to get extra deliveries of bottled water to sell, but organising a delivery of tank water took seven days so had to be carefully planned.
"It's factoring in when they can get it to us and also the quantity."
Mander is only allowed a delivery of 6000 litres but if he ran out, it would wreck the pump, he said.
"Everyone's in dire straits up here at the moment. We're probably about two weeks away from running out of water [at the store]. We're just praying for a little bit of rain."
Rain is forecast for Thursday and Sunday in Mangawhai.