Thursday, March 24, 2011

Population Change by Senate District

Last week, with the release of the block level census data, I broke down how much each congressional district was going to have to adjust. For the state Senate districts I considered just posting a list with their deviation from ideal population, but that's not as cool as a map. Before the fun begins though, we'll need to go over some background info to help understand what these maps mean.

Image Hosted by ImageShack.usThere are three maps below that I'm calling "rural," "burbs" and "cities." They are loosely grouped as follows; the rural districts that need to gain population, the suburban districts that need to lose population (some of which could be considered rural), and the city districts that need to gain population (some of which are suburban).

The maps are than labeled like this; first is the Senate district number, followed by the district's hPVI, and finishing with the districts deviation from ideal population size. Population numbers in black are overage, those in red with parenthesis are population underage. Said another way, districts with black numbers will need to shrink, and districts with red numbers will need to get larger.

Unlike US Congressional districts, Minnesota legislative districts don't have to have exactly equal populations between them, they only need to be equal within 10% of each other. This means that the district with the largest population can't have more than 10% of the population of the district with the smallest population.

Ideal district size therefore, is arrived at by taking the state population, 5,303,925 and dividing it by the number of Senate districts, 67. That comes to 79,163. With the 10% spread allowance that gives us population parameters of approximatively 75,000 on the low end and 83,000 on the high end. This means if a particular district is already within the +/- 4,000 range it doesn't have to change at all. Of course this doesn't mean it won't change.

Which brings us to the maps!

First, the map of the rural areas (SD's 1-5, 18, 20-24, 26-31).

Image Hosted by ImageShack.us

The districts in this map are 67,372 people short of ideal population, or slightly less than one district.

Second the map of the burbs (SD's 16, 17, 19, 25, 32-37, 48-49, 52, 56-57).

Image Hosted by ImageShack.us

These districts are over ideal population by 175,139 people, or slightly more than two districts.

Finally the map of the cities (SD's 38-47, 50-51, 53-55, 58-67).

Image Hosted by ImageShack.us

These districts are 107,767 people shy of ideal or slightly more than one district.

In short, the overall picture breaks down like this, the areas in the rural and cities maps will each lose a district and the areas in the burbs map will gain two districts. How it shakes out though, which districts move to where, is anyone's guess.

My personal preference would be to break some of the inner city districts out into the first ring suburbs in an effort to unpack the Twin Cities a bit. But that won't happen as long as the "perfect squares make the best district's" crowd is drawing the lines.

No comments:

Post a Comment