In what has been described as a case of 'beavers to the rescue,' several of the fuzzy little animals are busy rebuilding after one of their dams was breached.

The failure caused a substantial amount of drainage from an area of the Lewes Lake chain, Brad Finnson, a territorial Department of Environment water inspection officer, said today.

Finnson said he was called in after residents found a substantial amount of water in the lake was missing early this morning. They believe it drained into the Watson River.

'It was not the entire lake, it was (only) the southern portion,' Finnson said.

He said there was a series of dams that have been built by the beavers over the years. The drainage occurred after the lowest of the dams was 'breached' sometime last night.

'It's a substantial amount of water,' he said.

Finnson said after inspecting the area, he believed the breaching of the dam was a natural event. Local beavers are on the case, he said, and will repair the damage 'in short order.

'I'm not sure exactly how the breach happened ... (but) there's no evidence of human intervention or human activity.

'When I was out there, the beavers were busy at work putting it (the) dam back, putting in sticks, branches and mud,' he said.

He said the dam was likely breached by water because of its age but was confident in the ability of the beavers to repair it.

'This is a case of beavers to the rescue,' he said.