On a 4–0 vote taken on Wednesday night, Bloomington’s redistricting advisory commission settled on new boundary lines for the six city council districts, which will be recommended by the group to the city council.
The commission is set to meet next Wednesday (Sept. 7) to finalize its report on the recommended map.
The city council has until Nov. 1 to either adopt or reject the recommended map. If it’s rejected, the redistricting advisory commission has until Dec. 1 to respond to the council. Under state law, the city council has to adopt a new population-balanced map by the end of the year.
The work for city council redistricting takes place in the second year following the decennial census. The point of redistricting work is to restore population balance to the districts that might have shifted in the last 10 years.
Highlights of the new map include the prominence of 3rd Street as an east-west running boundary that is generally respected by every district—with one exception.
The 3rd Street boundary corresponds to the line between Bloomington Township and Perry Township. Political subdivisions like townships are among the “communities of interest” described in local code, which proposed new districts are supposed to avoid splitting.
Another highlight of the proposed new map is the way it avoids splitting most of the city’s neighborhood associations. One prominent neighborhood association that does get split is Elm Heights—its southwest corner winds up on a different district from the rest. Hoosier Acres, on the east side of the city, gets split along Meadowbrook Drive, which runs north-south.
Overall, the proposed new map is an improvement over the current districts with respect to the number of neighborhood associations that are split.
The proposed new map also reflects an improvement over the current districts with respect to “compactness”—a measure of how natural a clump the district forms, without a bunch of tendrils shooting off from a central area.
One approach to measuring compactness of a shape is to include the perimeter and the area as part of an equation. If a shape has a smaller perimeter but the same area as another shape, it’s considered more compact. The formula used by the city’s GIS staff to calculate compactness can range from 0 (for a line) to 1 (for a circle)—with 1 corresponding to the most compact shape.
If the districts in the current map are ranked on that definition of compactness from low to high, then compared to the districts with the same ranking in the recommended map, it’s clear that the recommended map is better on that score.
The recommended map has three districts with compactness scores of greater than 0.3. None of the current districts have compactness greater than 0.3. The most compact district in the recommended map is more than twice as compact as the most compact district in the current map.
The recommended map includes two central districts that do not touch any territory that is outside the city boundary. The current map has just one such district.
The recommended map has a population variance across districts of 7.5 percent, where variance is defined as the max population in a district minus the min population in a district, divided by 13,196.67, which is the average population in a district. That’s less than 10 percent, which is the accepted standard for the minimum variance.
If they were left in place, the current council district boundaries would result in 34.8 percent population variance.
After last week’s meeting, commissioners were left with just one legal map that they had considered in any detail. By this week, they received some additional maps from the public, created some of their own, and asked city council staff to generate some maps with specific attributes.
Voting for the new recommended map were: Kathleen Field, Michael Schnoll, Alex Semchuck, and Amanda Sheridan. Not able to attend the meeting was Mackenzie Colston.
A report from the commission, which is required under local law to accompany the recommended map, will get a vote next Wednesday (Sept. 7). That’s the first Wednesday in September, which is the defined deadline for the commission to forward its recommendation to the city council.
The city council has until Nov. 1 to act on the recommendation—by adopting the recommended map or by rejecting it. If the council rejects the map it has to state the reasons and refer the question back to the commission. The commission then has until Dec. 1 to respond to the city council. The city council has to adopt a new district map by the end of the year.
For interested members of the public who want to inspect the various maps considered by the commission, here’s a link: Esri-based city of Bloomington GIS redistricting tool.
For interested members of the public who want to inspect the recommended map with layers that can be toggled on and off for neighborhood associations, historic districts, and elementary school districts, here’s a link: Google Map set up by The B Square.