Lakeland Adventures commercial operator Simon Stewart said yesterday he would decide within the next 24 hours whether to start removing kayaks and other equipment from underneath the Log Cabin, which also houses Wanaka's i-Site.
The Log Cabin is the only building in the central business district on the Lake Wanaka shore.
It will be the first to bear the brunt of any flood.
"It is starting to get to the stage where we are a wee bit anxious about it. What we would prefer to do is to remove the kayaks from under the building without having to walk about in the water. We will make that decision in the next 24 hours," Mr Stewart said.
Wanaka's jetty is already inundated and the tops of the piles were barely visible in the grey water.
Driftwood is an obstacle to boating in the lake and the rivers.
Skipper James Blunt reported huge logs in the Clutha River near Albert Town yesterday, and piles of driftwood have started banking up around the lake shore.
Mr Stewart noticed one yacht had broken free of its moorings and had been washed ashore but he understood there was no damage.
Rain returned to Wanaka from early afternoon and Wanaka's civil defence team was monitoring the situation overnight.
Wanaka Community Board chairman Lyal Cocks said everyone was ready to swing into action if the lake level reached 279.4m.
"We will advise the at-risk people and provide support as needed," Mr Cocks said.
"We will use all the available media, then visit shops. I have a full list of phone numbers to ring," he said.
Wanaka's flood management procedure, under a joint strategy developed by the Otago Regional Council and Queenstown Lakes District Council in 2006, is to shift and protect stock first before installing barriers.
As with Queenstown, damage to the CBD can be exacerbated by wind-generated waves and debris.
Sections of Wanaka's CBD are also susceptible to surface flows from the overtopping of Bullock Creek.
The Otago Regional Council water information website reported heavy rainfalls in the Upper Clutha catchments this week.
Makarora had received 31.5mm in the 24 hours to 3pm yesterday (235mm in the last week).
During the same periods the Albert Burn received 57mm and 286mm respectively; Cascade Hut received 46mm and 388.5mm, and the Matukituki Valley received 15.5mm and 122.5mm.
The Clutha River at the Cardrona confluence was flowing at 592.2cumecs, less than 8cumecs below the first flood alert of 600cumecs.
The Matukituki River had dropped to 163.3cumecs at 3pm yesterday, down from about 850cumecs on Monday.
The Hawea River at the Clutha confluence was flowing at 13.8cumecs.
Lake Hawea's level yesterday afternoon was 344.8m and rising. Its levels are controlled by Contact Energy, within a range of 338m-346m.
