Since 1947 188km downstream of Lake Taupō, the Karāpiro Lake is the home of NZ Rowing.
Since 1929 Protected under the Historic Places Trust Arapuni has the largest capacity of any station in the Waikato hydro system.
Since 1941 The Gates help manage the volume of water flowing down the Waikato River, in response to inflows to Lake Taupō and energy demand.
Current work.
Our hydro stations on the Waikato River were constructed from the late 1920s to the 1970s and have worked hard to keep the country powered. We have a long-term hydro refurbishment programme to protect these assets to ensure they can manage water flow that looks after the environment but also can optimise energy from the awa.
In 2019 we begun a ~$90 million upgrade of the Karāpiro Hydro Station. This project replaced all three of the turbines, increasing the installed capacity to 1125MW and was completed in September 2025.
The next stations scheduled for upgrade are Ōhākurī, Maratai I and Ātiamuri.
Main works for the Dam Enhancement Project at Arapuni Dam are planned to commence in April 2026 and expected to take 24-36months.