A total of 45 people are involved in the search for Emma Beattie, who has been missing since Friday evening.
The search for the missing Rangiora 20-year-old is continuing today after Beattie left her Fernside home at 11pm on Friday. She hasn't been seen or heard from since.
Sergeant Phil Simmonds said eight teams, including LandSAR volunteers and police officers, are currently searching the Ashley River area.
The search is concentrated on the Hillcrest Rd area of the river with 32 people searching for Beattie in the field, with an overall total of 45 involved in the search effort.
"Teams are focusing on buildings, properties and hedgerows in the area," Simmonds said.
"Search conditions are very hot and fresh teams will be taking over this afternoon."
A Search and Rescue dog team is also involved.
Anyone who may have seen Emma Beattie is being urged to contact police immediately.
Police earlier said they have concerns for her wellbeing.
She has long blonde hair, and could be wearing orange and black Nike shoes. She could also be carrying a brown backpack with rope straps.
Information can be passed on to Christchurch Police on 03 363 7400 or Crimestoppers on 0800 555 111, and quote the file number 171202/9451.