WESTPORT — A driver involved in a four-car crash near one of the town’s busiest intersections in September has been charged with driving while impaired.

John Siddell, 51, of Westport, in addition driving under the influence of drugs or alcohol, was charged with failure to obey traffic control and failure to drive in an established lane in connection with the accident.

Officers were dispatched Sept. 9 to investigate an accident involving four vehicles on Riverside Avenue, just south of its intersection with Post Road West.

An officer talking with the driver of what police said was the “at-fault” vehicle — identified as Siddell — reportedly smelled an alcoholic odor and said that Siddell’s “speech was slurred and incoherent at times.”

Siddell, who was injured in the accident, was transported by Westport EMS to Norwalk Hospital.

Based on additional evidence and the results of Siddell’s toxicology report, which police obtained after being granted a search warrant, a warrant for Siddell’s arrest was issued.

On Dec. 1, Siddell turned himself in at Police Department headquarters, and was formally charged.

He was released after posting $10,000 bond and was scheduled to have been arraigned Dec. 8 at state Superior Court in Stamford.