From the U.S.C.G. Auxiliary:
Weighing anchor doesn’t have to be difficult. The Coast Guard Auxiliary recommends these simple steps:
• Motor up to the anchor until the line is vertical
• Pull up the anchor
• If the anchor is stuck motor across the anchor location. This will usually break the anchor loose
• If the anchor still won’t break, circle the anchor location with a taunt anchor rode until the anchor breaks loose.
Sometime the anchor will not break no matter what is tried and another anchor is added to the deep.
To prevent this situation connect a line to the tripping ring on the crown of the anchor with a buoy attached to mark the position on the surface. Motor up to the anchor location and retrieve the tripping line. Pulling up will disengage the flukes from the sea bottom.
Another method will require another boat. Drop a chain around the anchor rode until it covers the shank. The helper boat pulls on the line with the chain attached and pulls the anchor loose by pulling on the crown.
The Coast Guard Auxiliary reminds boaters to never anchor from the stern as you only anchor. This could be a deadly situation.