The huge sinkhole that has opened up on Blyth beach was caused by the heavy rainfall, the council has said.
The Coastguard and other emergency services were called out to the south end of the beach to assist Northumberland Fire and Rescue Service on Monday afternoon.
The Senior Coastguard Operations Officers and the Blyth Coastguard Rescue Team attended along with police.
A cordon was put in place and crews remain on scene on Tuesday attempting to fill the hole.
Police have said that the hole is approximately 8ft deep, 8ft wide and 20ft long.
Northumberland County Council has said they will be monitoring the situation over the coming days.
A spokeswoman said: "The sinkhole developed due to the very heavy rainfall over the weekend combining with the highest tide of the year.
"When the strong force of water out of the pipe at Meggie’s Burn hit the incoming high tide it made the water divert northwards where it came into contact with the groyne sea defence.
"As the sand level was higher on the north side of the groyne, the force of water washed away the sand underneath the groyne causing the sand to collapse and a hole to form.
"The hole has been taped off for safety and will be monitored over the coming days.
"We are currently working to divert the flow of the burn back to its natural water course to help address the cause of the problem."
A spokesperson for Northumbria Police said: "Shortly after 12.15pm yesterday (Monday), police received a report of a sink hole on Blyth Beach by the beach huts.
"It was reported to be approximately 8ft deep, 8ft wide and 20ft long.
"The relevant partners were contacted to secure the hole and a cordon was put in place for public safety until it is filled in.
"No one was injured."
