Lake Wanaka levels have dropped to 276.5m above sea level, which has left an expanse of mudflats and the outer reef at Bremner Bay exposed.
The shoreline along Roys Bay and Lower Ardmore St has also receded, by up to 5m in some areas, with the overall lake level dropping 1m in the past month.
While the low lake levels are normal for this time of year, the monthly mean outflow of water from Lake Wanaka is more than 15 cumecs below average, down from a historic mean of 204.960 cumecs to 189.831 cumecs, a 7% drop.
The level of Lake Hawea is also a metre below its monthly average and a 1pm recording yesterday was 341.8m above sea level. Lake Hawea is a controlled dam with water storage used to power the Clyde and Roxburgh hydro schemes, run by electricity supplier Contact Energy.
Contact spokeswoman Anne-Marie Shepherd said the below-average lake levels would continue to be monitored by the power company into winter.
Lake Hawea's monthly mean level for March was 343.152m, down from its historic mean level of 344.100m.
The lake has dropped a further 1.4m during April with its monthly outflow in the Hawea River also significantly lower, down almost a third from a historic average of 49.6 cumecs to 32.7 cumecs.
The level of Lake Wakatipu was 309.469m, normal for this time of year, while its outflow in March, also recorded a drop of 15%, averaging 151.3 cumecs, down from a historic mean of 179.9 cumecs.
