But Tasmania Police Inspector Tim Dooley said police remained hopeful she would be found unharmed.

Jodi Michelle Eaton was last seen at a house in Sage Court, Bridgewater, at 2.30am on Saturday.

The 28-year-old mother of two and her partner had been drinking with friends at the address, but he had gone home earlier in the night.

Inspector Dooley said other people who attended the gathering last recalled seeing Ms Eaton at 2.30am, when she had fallen asleep at the house.

But when the resident woke at 7am the next day, Ms Eaton had gone.

Inspector Dooley said Ms Eaton was expected to pick up one of her children from their father the next day, but missed the appointment, something she had never done before.

"This is completely out of character for her," he said.

Inspector Dooley said Ms Eaton's family and partner were extremely concerned for her welfare. She was reported missing by her mother on Sunday night.

He said attempts to contact her had failed and her phone appeared to be turned off.

Police searched the area by helicopter, foot and boat yesterday, looking for signs of Ms Eaton or her belongings on the shoreline of the River Derwent or in nearby bushland.

Forensic police were also searching a property in Sage Court yesterday.

Inspector Dooley said the search had not yet become a murder investigation, but said that could change.

"We are very concerned about Jodi's welfare. We're not going to close our mind to any options at this stage," he said.

"As time goes on, we get increased anxiety that we will find her safe, but we maintain hope that that will be the case."

A police command bus has been set up at the Bridgewater fire station and will be manned from 8am. Anyone with information is asked to contact Crime Stoppers on 1800 333 000.