Just four months after permission was given to extend lake level minimums for hydro lakes, there now appears to be too much water in them.
After a dry start to the year and a dry winter there was a fear there would not be enough water in the hydro lakes to meet power demand.
Permission was granted to hydro power generators to go below their minimum levels which would allow more power to be produced.
But the lake levels did not need to go below their expected level as the rain arrived. And it kept coming and coming.
Now hydro generators have too much water.
Meridian Energy had started releasing water from Lake Pūkaki as it was close to reaching its maximum level.
The level stood at 532.49m yesterday afternoon.
The water is being released from the Pūkaki spillway into the dry Pūkaki riverbed.
Meridian Energy advised currents would be unpredictable and river flows changing for the duration of the spill.
The Waitaki District Council has advised campers to be watchful when camping and to not get too close to the water.
Water levels will increase gradually until about 70 cumecs of water is being released.
Due to expected rainfall, the power generator has not established an end date for this release.
The maximum level allowed for the lake is 532.5m and Meridian Energy said just before Christmas it had to release water to make room for expected rainfall.
Lake Hawea, the storage lake for the Clyde and Roxburgh dams, had been half full into August but had bounced back fast and was now sitting at 345.45m. It has a 8m range with a maximum allowable level of 346m.
Spilling has been occurring at the Clyde Dam on and off for several weeks.
Hydro lakes provide about 57% of all power generation in New Zealand.
