MERCURY NEWS

8 September 2026

Keeping the water flowing:
Mercury replaces vital hydro equipment

The new screen cleaner at Waipapa Hydro Station was installed and commissioned this year.

Vital equipment which ensures Mercury’s hydro stations can continue to generate electricity is about to be upgraded with modern equivalents.

Mercury is investing $4 to replace screen cleaner machines at its Waipapa and Whakamaru hydro stations on the Waikato River.

It is part of a wider programme of maintenance works for the Waikato Hydro System, to ensure its longevity to meet the country’s renewable energy demand.

Each hydro dam has water intake screens which work as a filter, preventing debris such as sticks, weeds and rubbish from entering the penstocks which carry water to the hydro stations' turbines.

Screen cleaner machines, stationed at the top of the dams, are then used to remove the debris from the intake screens.

Joselito Villena, Bede Geoghegan and Cameron Crawford at Waipapa Hydro Station. They have been working on the installation and commissioning of the new screen clear machines.

This reduces blockages that can lower power generation, while also improving safety and reducing the need for manual cleaning.

Mercury’s Acting Programme Manager, Generation, Eshan Verma, said the screen cleaners were critical to the hydro stations' operations.

"Keeping the water intakes clear of debris means we can maintain good water pressure down to the turbines, enabling us to generate electricity when it is most needed."

Eshan said the screen cleaners at the top of Waipapa and Whakamaru hydro dams had reached the end of their useful life.

“We've made improvements to them over the years, but a decision has been made to fully replace those units.”

The screen cleaner at Waipapa was installed during winter 2026 and work on the Whakamaru cleaner was planned for spring 2026. The water intake screen at Whakamaru will also be replaced.

Eshan said Ātiamuri will be the next hydro station to have its water intake screens and screen cleaner machine upgraded over the next couple of years.

MHM Automation was supplying the screen cleaner replacements and would be responsible for installing the new machines.