With New Year’s Eve falling on Monday this year, law enforcement officials are keenly aware that means an extra long weekend for partying and increased potential for tragedy that comes with drinking and driving.

But even without that, local and state police in the Merrimack Valley and Southern New Hampshire would still plan, as they are this season, to ramp up their chances to stop drunken drivers with sobriety checkpoints and roving patrols.

In New Hampshire, state police aren’t planning any sobriety checkpoints, but they will have more troopers on the highways.

“Checkpoints are very effective, but typically what we try to do is keep the roving patrols out this time of year,” said Sgt. Scott Carr, the assistant commander for state police Troop A in Epping.

Carr said he believes patrols work better than checkpoints this time of year because they allow police to fan out across the region. A checkpoint would concentrate police in a single area, he said.

“We want to get the most bang for our buck,” he said.

In Lawrence early today, state and local police planned a sobriety checkpoint on Route 114.

The roadblock was set up at the Central Bridge and state police brought along the Batmobile, a 40-foot bus equipped with drug and alcohol screening devices, booking rooms, and holding cells.

The sobriety checkpoint was part of a $1.1 million grant initiative state police launched in mid-December, according to Trooper Eric Benson, a state police spokesman.

Benson said drivers also can expect “a heightened state presence” on North of Boston highways this weekend, courtesy of the grant money.

Acting Methuen police Chief Katherine Lavigne, noted that many folks have both Monday and Tuesday off, creating a very long weekend.

She said officers will be vigilant in looking for impaired drivers and responding to noise and party complaints.

“As you can imagine, people are in the party mode early so we have to be prepared early,” Lavigne said.

Staff reporter Gordon Fraser contributed to this article.