Starting Jan. 9 Boston drivers will have to slow down a little.

The speed limit on city streets will drop to 25 mph from 30 mph, the city council decided Wednesday.

The change is an important move for the city’s Vision Zero plan, which aims to eliminate traffic-related fatalities by 2030.

"The enforcement of this safety initiative will make our streets safer for drivers, pedestrians and bikers alike," City Councilor Frank Baker said in a news release. "I look forward to its implementation, as well as the creation of innovative traffic calming measures."

Although a significant number of improvements have been made to Boston's streets in recent years, traffic related tragedies continue to persist. To date, 17 people have been killed in traffic crashes on city streets in 2016. Twelve of these people were killed while walking and five were killed in a motor vehicle.

Slower speeds will help decrease these numbers, saving lives and preventing injuries. Studies show that there is a direct link between the speed that a vehicle is traveling when a crash occurs and the likelihood of a fatality or severe injury resulting from that crash. At 20 mph there is a 17 percent likelihood of a fatality or severe injury occurring, and that number jumps to 79 percent at 40 mph.

"The 30-mile-per-hour benchmark really does make a difference. It can literally be the difference between life and death for a lot of people — especially for vulnerable people like children and elderly," said Andrew McFarland, community engagement manager with the Boston-based safe streets advocacy group Livable Streets Alliance.