Portion that are 'alcohol related': 1/3rd, about 10k total
I'm always a little curious when I hear 'alcohol related' without a description of what information was gathered because MADD and others have done such a good job obscuring the number away form anything meaningful. Things they've included in the past:
Accidents caused by a sober driver hitting a driver who had been drinking.
Accidents where one or more passengers were intoxicated even if the driver wasn't
Accidents where beer cans or other alcohol containers were found in the wreckage regardless of circumstances.