Lake Te Anau and Lake Manapōuri levels update

Following an extended period of low rain in the Waiau catchment, both Lake Te Anau and Lake Manapōuri have entered the Low Range of the Operating Guidelines for the Levels of Lakes Manapōuri and Te Anau.

The Guidelines set in place a number of requirements for operating in the Low Range, including minimum lake levels in the equinoxial months of March and April (and October and November). This is where we must use best endeavours to minimise the effect of equinoxial wind patterns and subsequent wave effects on exposed shorelines.

We’ve been monitoring the situation very closely. We recognise there is an increasing risk that the Lake Te Anau equinoxial limit could be departed from should the current dry conditions persist. Therefore, we have engaged with the Lakes Guardians, Te Ao Marama, Fish & Game, and Environment Southland who have allowed the flow at the Te Anau Lake Control Structure to be stepped down below its normal 115 cumec per second minimum.

The flow will reduce towards an 80 cumec limit, as provided for under resource management consent conditions. This will slow the rate of drawdown on the lake level and minimise the risks associated with an incursion into the equinoxial zone.

We are also managing generation at Manapōuri Power Station to reduce the risk associated with the equinoxial requirements in Lake Manapōuri. More details on The Operating Guidelines can be found here.

ENDS