Unhappy with his fellow city councillors’ efforts to redraw the political boundaries of nine City Council seats, Dorchester Councillor Frank Baker plans to file his own map next week.

The nine district councillors and their four at-large colleagues are facing a Nov. 7 deadline to get a map finished, a year before the 2023 municipal election. Three maps have been proposed: One from Councillors Liz Breadon and Brian Worrell, another from Councillor At-Large Erin Murphy, and a third from Councillors Ricardo Arroyo and Tania Fernandes Anderson.

Each map takes a slightly different approach to the redistricting effort, which occurs every ten years. A population boom is driving councillors to move precincts out of South Boston-based District 2, which has to shed people, while Dorchester-based District 3 needs to gain people.

Baker, elected in 2011, was present for the last round of redistricting, an exercise that left a bad taste in his mouth because his Dorchester-based district lost precincts, he said Friday.

With Dorchester Avenue as the district’s spine, Baker said he wants to pick up the precincts around St. Gregory’s/Lower Mills, which are majority Black and pick up Fields Corner precincts that have a large Vietnamese population. He also expressed interest in Andrew Square and the Anne Lynch public housing development.

The currently proposed maps move parts of Fields Corner into District 3, but split the precincts along Dorchester’s southern border between Districts 3 and 4. Mayor Michelle Wu, who would be faced with signing or vetoing any map that reaches her desk, has not publicly weighed in but has indicated interest in uniting the Vietnamese population in Fields Corner within one district.

Baker has previously called the map proposed by Arroyo and Fernandes Anderson a “non-starter” for him, because he disagrees with a District 3 that runs from the Neponset River up to Copley Square. That map seeks to pull together the Vietnamese community in Fields Corner with the Asian American Pacific Islander (AAPI) population in the South End.

But splitting Adams Corner from District 3 and putting it into District 4 “would be similar to taking Nubian Square out of Roxbury,” Baker claimed.

Baker, who spoke to the Reporter outside his office on Friday after councillors met on the topic of redistricting for nearly three hours, said he would file his map “early” next week.

Councillors plan to hold additional working sessions and redistricting hearings in the coming weeks. The next hearing is slated for Tuesday, Oct. 11 at 5 p.m., inside City Hall.

Baker said the last round of redistricting in 2012 broke up Dorchester’s parishes and he wants to reunite them under one District 3, referencing the geographic boundaries established by the neighborhood’s heavily Catholic population in the 20th century. Over the last 20 years, the Archdiocese of Boston, rocked by the child sex abuse scandal and shrinking coffers, has closed churches and merged others.

“We have very clear parish boundaries that I believe should be respected,” said Baker, who grew up in the St. Margaret’s Parish in Columbia/Savin Hill area.

Councillor At-Large Julia Mejia said she is from St. Ambrose’s Parish, which is in Fields Corner, but “a lot has changed.” Black and brown residents don’t identify themselves to her as saying they’re from “such-and-such parish,” she said.

Jamaica Plain Councillor Kendra Lara said parishes can be considered communities of interest for the purposes of redistricting, both from a cultural and religious perspective, but they are “secondary and tertiary” to what the council is tasked with doing under the federal Voting Rights Act: Empowering racial minorities by creating electoral opportunities.

Lara also claimed that none of the maps seek to break up the South Boston neighborhood. Murphy said that was incorrect; her map takes two South Boston precincts out of District 2 and gives them District 3.

Murphy also pushed back on another claim from Lara, made during a previous redistricting hearing. Lara said that the Murphy map would lead to the City Council getting sued if passed, arguing that it “packed” too many people of color into one district.

Murphy said her map, which attempts to unite Mattapan under one district, is legal because it does not weaken Black voting power, as it has for decades elected people of color, from Charles Yancey to Andrea Campbell and Brian Worrell, who took office this year.

Arroyo said District 4 has to add white people, and it can’t go into his District 5, which includes parts of Mattapan, because the precincts on the border are made up mostly of people of color. “We have to accept as a body that nobody’s going to love all of the lines of the district,” he said.