Environment Canterbury has issued a flood advisory recommending voluntary evacuation for residents and farmers near the Rakaia River on Thursday night.

In an update at 9.50PM, the regional authority said river flows had peaked at about 4,800 cubic metres per second at Fighting Hill and were expected to move through the lower parts of the river during the evening.

The agency said out-of-river flooding to nearby farmland and areas around State Highway 1 was possible.

“Together with Selwyn District Council Civil Defence, we are recommending voluntary evacuation of people and stock of adjacent areas as shown in the included flood model maps,” Environment Canterbury said.

The advisory includes the North and South Rakaia Huts and rural land adjacent to the river downstream of State Highway 1.