Nocton Road (the B1202) is closed at the junction with the park in Potterhanworth due to a collision.
According to a Lincolnshire Police report, the incident was called in at 4.14pm this afternoon (Friday).
A single car is involved and one man is said to have been injured.
Motorists are advised to avoid that road.
Stagecoach East Midlands says on social media it has had a knock on effect on local bus routes.
It Tweeted that due to the collision between Potterhanworth and Nocton the 17.55pm service 31 from Sleaford to Lincoln will not be serving Nocton or Potterhanworth or Lincoln.
“The driver has been instructed to stop at all available safe places to let of passengers off. Apologies for any inconvenience,” it states.