The Ballarat Yacht Club commodore was witnessing something he had not seen for seven years: a yacht on Lake Wendouree.

Heavy rain at the weekend, along with regular flows of recycled water, stormwater and ground water have helped boost the lake to levels not seen since early this decade.

With this in mind, Charles and Di Weatherly and sailing partner Chris Curwen-Walker took their vessel Scorpion out for a sail.

''I was just standing there (Tuesday) night watching them sailing and I thought `I can't believe it,'' Mr Canny said.

It is believed to be the first yacht to have sailed the lake since water levels dropped beneath 700 millimetres below full in 2003.

More crafts can be expected to take to the water in coming weeks and the club is planning a season opening at the end of October.

Ballarat City Council measurements indicate the lake is now 650 millimetres below full.

Only four weeks ago it was 950 millimetres below.

The council's sustainability executive manager Ian Rossiter said the present levels were about 300 millimetres higher than council modelling had anticipated.

''We're two to three months ahead of where we'd thought we'd be,'' Mr Rossiter said.

He said while there was now sufficient depth for non-powered craft to go on the water, the lake was still off-limits to motor boats at this stage. Another 50 millimetres and 100 millimetres is required for powered boats to get back on the lake.

Until that arrives, activities needing motor-boats for safety purposes, such as rowing training and yachting regattas, would not proceed.

''But we're not far away from that. The really good news is we've got a significant depth of water over most of the lake now.''

''I think we can safely assume that in the next month or two we would be fairly likely to see the lake get to the point where we can open it powered motor vessels.'' He said the only restriction on that would be the dredging of the lake's rowing course, expected to start in coming

months.

Ballarat Rowing Association president Eric Waller said the rapid re-fill of the lake had taken everyone by surprise.

Ballarat Fly Fishers' past president Craig Coltman said fishing enthusiasts were confident the lake could be re-stocked with brown trout by Christmas.