FOR MANY OF US, the Thanksgiving itinerary will involve something far more hazardous than going over the river and through the woods. Around here the paths to holiday get- togethers are fast lanes, loaded with deadly dangers on this busiest travel weekend of the year. We'll underline the familiar public service warning about safe driving, although it never seems to be heard by the worst offenders: the killer-drivers who have been drinking. If it makes any further difference, those who intend to partake of any spirits should be advised that police throughout this region and up and down the coast will not be taking a holiday. They will be on, off and above the roads, with radar and with little patience -- the less, the better -- for motoring lawbreakers.

So much for that legendary "other" driver, that "someone else" who is always regarded as the real threat on the road. The best move the rest of us can make is to keep drinkers away from the driver's seat. That's been the message all fall from the Washington Regional Alcohol Program, a coalition that has been coming up with practical suggestions on mass temperance. With the cooperation of restaurants, bars, hotels, auto dealers and civic leaders throughout the region, WRAP is urging groups of people to designate one person to abstain from alcohol and to do the driving for the rest.

That's hardly a complicated or demanding mission. It could well prove to be the life of the party.