Boston — Roads and drunken drivers - two of America's most deadly companions - soon may be getting together a lot less often.
Within the past seven months, lawmakers in 30 states and the District of Columbia have enacted new laws aimed at keeping intoxicated motorists off both highways and byways.
The newest and potentially most far-reaching of these statutes, due to take effect in Massachusetts Sept. 1, makes conviction and punishment more certain for the drunken driver, as well as the liquor establishments that habitually serve these problem drinkers.
Although the measure is not as tough in penalties as some Bay State lawmakers wanted, it does make it impossible for repeat offenders to avoid penalties, with a mandatory 60 days in jail awaiting anyone convicted for driving while intoxicated (DWI) for a third time. The penalty also includes loss of driver's license for five years plus a $500 to $1,000 fine.
Under the law, second offenders spend seven days behind bars or two weeks in an alcoholism residential treatment center. They also face a $200 to $1,000 fine and a two-year license suspension.
Unlike a few other states that have similarly moved to crack down on drunken drivers, Massachusetts will not be required to jail a first offender unless a fatal accident is involved. But there is a 30-day license suspension and a fine of at least $100. In addition, the sentencing judge can order attendance in an alcohol treatment program.
A new category of crime, that of vehicular homicide, covers drunk driving that results in a death. Such convictions will mandate a minimum one-year imprisonment penalty. A driver's responsibility for a highway fatality while under the influence of liquor has in the past has been considered ''misconduct'' instead of a felony in Massachusetts.
More than one-half of the 341 traffic deaths in the commonwealth this year have been alcohol-related, according to Gov. Edward J. King, who pressed for passage of the anti-drunken driver statute.
Meanwhile, in neighboring Rhode Island, a new law to make the state's highways safer has been in effect since July 1. It includes a one-year license suspension for a first offense and 10 to 20 days in jail for second DWI convictions. The measure also establishes the presumption of intoxication if motorists stopped for a breath test are found to have a 0.10 percent alcohol content in their system.
New Jersey's latest response to drunk driving is a mandatory six-month license suspension for first-time convictions.
While road-safety specialists and other experts differ as to which state has the toughest new DWI-control measure, they generally agree that Tennessee has the toughest statute, with a mandatory two days in jail for first convictions.
With most 1982 state legislative sessions having ended, those pressing for more effective curbs on drunken drivers are looking forward to January when lawmakers return to work, says Catherine Yoe of the Highway Users' Federation based in Washington, D.C.
Still being watched closely, however, are current proposals in at least five states - California, Michigan, New Jersey, Ohio, and Pennsylvania - where legislative sittings are continuing or scheduled to resume sometime this fall.
Across the nation, a particular push to raise the minimum drinking age to 21 is expected next year. That recommedation was made earlier this summer by the National Transportation Safety Board (NTSB).
Of the 25,000 people killed last year in liquor-related motor vehicle accidents, 8,484, or about 35 percent, were between the ages of 16 and 24, observed NTSB chairman James -Burnett. He called this death toll of young Americans ''a national scandal.''
''Raising the drinking age to 21 could help save thousands of young lives,'' he declared in announcing his agency's conclusions.
In its determination to help hike the drinking age, NTSB has sent letters containing its recommendations to governors and legislators in the 35 states where liquor is legally available, in some if not all forms, to people under 21.
The 15 states currently with the 21-year-old requirement are Arkansas, California, Illinois, Indiana, Kentucky, Maryland, Michigan, Missouri, Nevada, New Mexico, North Dakota, Oregon, Pennsylvania, Utah, and Washington.
The District of Columbia and nine other states - Colorado, Kansas, Mississippi, North Carolina, Ohio, Oklahoma, South Carolina, South Dakota, and Virginia - require their residents to be 21 to obtain hard liquor, but youths as young as 18 or 19 can buy and consume beer or wine.
This year, four states have raised their drinking ages - Connecticut and New York from 18 to 19, Ohio for beer only from 18 to 19, and Maryland from 18 to 21 for beer.