Hamurana Spring is the deepest natural fresh water spring on the North Island of New Zealand. Located to the north east of Lake Rotorua, the spring emerges from a rocky area within a Department of Conservation reserve.
The spring is 920 feet (280 m) above sea level and is approximately 15 metres (50 ft) deep. It produces an estimated 4 million litres of crystal clear water per hour at a fairly constant temperature of 10 degrees Celsius. The spring flows as a stream for approximately one kilometre before joining Lake Rotorua. In summer the stream is home to rainbow trout who prefer the cooler temperature of the spring water.