The pilot reported that, after the cargo was loaded onto the Beech 58 for the night flight, he performed a contamination check, and the airplane was free of contamination.
After performing the run-up checks, he activated the anti-ice systems and taxied onto the runway at the airport in Denver.
He noted that air traffic control had reported about an hour before the accident that about 1/2 inch of wet snow had accumulated on the runway and that the runway surface was unplowed and “slushy.”
He started the takeoff roll and, as the airplane rotated, slush from the runway hit the windshield, and the pilot lost all forward visibility.
Once airborne, the airplane drifted left, and the pilot attempted to abort the takeoff.
He reported that he “had difficulty maintaining directional control” and that he tried to land the airplane back on the runway, but it hit the side of the runway and struck a runway light.
Once the airplane was stopped on the runway, he taxied it back to the hangar.
An examination of the airplane revealed that the right wing sustained substantial damage.
Probable cause: The pilot’s failure to maintain airplane control during a rejected takeoff from a slush-covered runway at night.
NTSB Identification: CEN15LA144
This February 2015 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.

An ITO (Instrument Take Off) procedure should have been followed. Pitch ‘4 bars, maintain heading via DG until positive climb and altitude sufficient for gear retraction. If he was not so prepared and rated he should have not attempted to fly till the runway was cleared.
I think the probable cause needs to be revised. It should read…
Probable cause: Airport failure to remove contaminants from runway surface as part of “normal” winter maintenance.
Contributing Factors: Pilot’s decision to depart from a contaminated surface that was improperly maintained.
And that some undetermined amount of slush affected the flying surfaces and controls such that the pilot had difficulty with directional control.