An ambitious overhaul of how the Baltimore Police Department segments the city into nine police districts is set to take effect Sunday morning. Officials hope it will streamline policing in the city.

The redistricting is the first such effort in nearly 70 years, the result of a long and sometimes contentious process that included carve-outs of neighborhoods that had long known certain police commanders.

Under the newly drawn districts, police department officials have shifted certain areas of the city that had more violent crimes into larger districts that are historically even more violent, a Baltimore Banner data analysis found. To that end, the movement of borders sparked pushback from neighborhood groups who objected to the changes, along with the City Council members who represent them.

But police officials have maintained the adjustments are necessary to smooth out workloads and for other logistical reasons. They’ve argued the new districts keep many neighborhoods more unified than under the previous borders, which helps with community policing. Though the districts haven’t changed in decades, the city has, including seismic population shifts and altered crime trends, police officials have said.

The Baltimore Banner thanks its sponsors. Become one.

“We used a data-driven approach to develop sectors and posts that balances officer workload, better aligns with our staffing plan and ensures we are providing policing services more equitably for all neighborhoods across the City,” Deputy Commissioner Eric Melancon said in a statement Friday.

The police department defines workload by the hours officers spend responding to 911 calls, but the Banner’s analysis found the attempts to distribute those hours equally under the new borders inevitably will lead to other inequities.

The most notable effect will be to saddle smaller districts such as the Western, Eastern, Southwestern and Central with areas that have seen more shootings, homicides and aggravated assaults.

Despite resistance from some residents, policing experts have said the redistricting plan could allow district commanders to better address patterns of crime that span across neighborhoods that were dissected under the old map. Still, those experts cautioned that police officials would have to follow up and make sure areas of the city aren’t neglected under the new borders.

The redistricting effort was one of the main goals of Mayor Brandon Scott and a significant undertaking for a police department still navigating its federal consent decree. The City Council approved the new maps 12-3 in October.

The Baltimore Banner thanks its sponsors. Become one.

A previous version of this story inaccurately described the size of the smallest police districts.

Baltimore Banner Data Editor Ryan Little contributed to this report.

bconarck@thebaltimorebanner.com