A large speedboat fell off a trailer at around 3.30am and was clipped by a lorry at junction 8 on the clockwise stretch.
Drivers could not access the motorway at J8 after the entry slip road was shut, and one lane of the carriageway also stayed closed until 7.45am while the boat was recovered.
The incident caused delays into the morning rush hour, with tailbacks of 12 miles to junction 5 in Kent.
Onlookers were quick to make light of the situation, with many joking about the amount of rain received recently.
Eyewitness Rusty Lowe tweeted: "Has Noah finally sent his arc after the rain."