Azavea Atlas

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Pennsylvania Congressional Redistricting: We Have a Plan!

After months of only rumors leaking out of the Pennsylvania Capitol about the redrawing of the state’s congressional districts, a map was finally released yesterday. It was supposed to be released last week. Then it was delayed until Monday. Then Tuesday. Then a PDF came out yesterday and the shapefile, which allows us to do a geographic analysis, early this morning. The Cicero team couldn’t wait to get our hands on it!

At first glance we were taken aback, most notably by District 7, which got more “Wow what is that?” remarks in the office than the earthquake. There is a lot to say about this monstrosity, certain to be a poster child for future gerrymandering studies. We’ve been able to perform some basic GIS analysis on the new districts today and will present some findings below. Next week, we’ll write about some of the methods used to create the numbers we are presenting.

First off, here’s the numbers you have been waiting for: compactness, demographics and voting tendency for the current and proposed congressional districts:

UPDATE 12/19/2011: We have added statistics for the Democratic congressional redistricting proposal:

As you can see, using both the Polsby-Popper and Schwartzberg methods of calculating district compactness (read up about how those are calculated by taking a look at our gerrymandering white paper), the proposed congressional districts are slightly less compact than the districts currently in effect. While that may not seem like a lot, keep in mind that Pennsylvania’s current districts are already some of the least compact in the nation, according to our study. District 7, represented by Patrick Meehan (R), takes the honor of having the eighth least compact congressional district in the nation. Of all the newly drawn congressional districts, it is the fifth least compact in the nation. Have a look for yourself:


District 7 snakes its way through southeastern Pennsylvania in five counties. In some cases, the district is as narrow as 800 feet across, like here along the Pennsylvania turnpike:

In a matter of seconds, you could drive in three separate congressional districts, without even speeding! But I hope you brought your boat, or at least a swimsuit. Just a few miles northeast of there outside Norristown, District 7 leaps across the Schuylkill river. To stay in the district, you’ll need to cross – but there’s no bridge.

Why are the lines so screwy? We could speculate that it may be for incumbent protection. In its new form, District 7 now has a GOP advantage by almost four points, reversing the five point Democratic advantage in the current plan. One thing is for certain: it looks like we’ll have plenty of material for another gerrymandering study. If you want to stay up to date on all of our redistricting work, follow the Cicero team on twitter.