Internet giant Google has confirmed a large balloon, spotted in Lake Brunner this week by a local boater, was one of its Project Loon wi-fi internet balloons.
The balloons are designed to provide an airborne network of internet coverage in parts of the world where reliable internet is hard to come by.
John Welsh, who has a holiday home by the lake, said he was out on a pleasure run with some friends on Lake Brunner on Tuesday when he saw a big white object on the edge of the lake.
"We came over to have a look, it was like a big weather balloon with solar panels on it, floating in the lake, caught up in some weeds, just sitting there.
"We did have a look to see where it came from, though we didn't get too close with the boat in case it got caught up in the propellor. There was all this electrical gear you could get hold of and pull it up with."
A spokesman for Google said it had been periodically testing the balloons, which were being released from Tekapo, since the project was launched in June last year.
He said a team had been back this week to check on a series of the balloons, guiding them back down to earth near the lake.
"It's all solar powered so they can communicate with the balloon, and it's padded with styrofoam, it comes down quite gently so they can reuse the electronics in it."
The spokesman said each balloon had a life span of about 100 days, after which it was guided down for the technology to be reused. He said the team headed out on to the lake on a boat and recovered it about 2.30pm.
"They had the help of some locals from Moana, which they were very grateful for."
In July, it was revealed several unidentified flying objects over Greymouth and Hokitika were Google balloons.