MetService has downgraded the rain warning for Buller from red to orange

But those who were evacuated in Westport last night are being advised by Civil Defence to stay another night with friends and family, or at a community welfare centre.

Hundreds more people were evacuated today.

People in Westport who have not yet been evacuated are advised to shelter where they are, and if there is a risk to life then call 111.

There are now six welfare centres: Phelan Hall, Westport South School, Salvation Army on Henley Street, Club Buller, NBS Theatre, and Carters Beach Top 10 Holiday Park.

Local Civil Defence controller Bob Dickson says river conditions are still extremely high and dangerous, with more rain expected overnight.

He says the situation will be reviewed mid-morning.

Dickson says there is plenty of food in Westport and there's no need to buy more than needed for a day or two.

People are being told to stay off roads and only travel if it's essential.

They're also being asked to conserve water.

At the north of the South Island, the Tuamarina and Spring Creek townships, near Blenheim, have been evacuated alongside Renwick and part of the Lower Wairau area.