California Redistricting - Where The Rubber Meets The Road

One of the main influences on how California Assembly and Congressional District lines will be redrawn is redistricting data from the 2010 Census, as well as population data from the Statewide Database. California's data is not yet complete (although the Census Bureau has already told the state it did not gain enough population during the 2000's to warrant any additional Congressional Districts), but should be available no later than April 1, 2011.

For an example of what California's Census map (by county) will look like after all of the data is in, let's look at a completed state, Iowa:

(Mouse over individual counties for county-by-county population data and trends.) Conveniently, Iowa's Congressional Districts follow county lines.

Overall, Iowa has lost population; as a result, it will lose one Congressional District, and therefore a House seat, after apportionment. Interestingly, Iowa also uses a Redistricting Commission of sorts, though significantly smaller than California's:

For the first time in two decades, Iowa is losing a seat in Congress because population growth has been heavier elsewhere. That, combined with what some experts say is a national trend toward transparency, could present the biggest challenge yet to a redistricting system enacted in 1980 that allows three nonpartisan staffers to draw the lines.

"That's going to be a more potentially controversial decision, getting rid of one seat and moving other seats around to swallow up territory that is lost," said Bruce Cain, a political science professor at the University of California-Berkeley . "It's going to be a more severe test of the system than if Iowa was adding a seat or staying the same."

At least California will maintain the same number of seats; in that respect, its job may be easier; then again, it has to redistrict 12 times the number of Districts.

Currently, each Congressional District across the country, encompasses about 700,000 people. Because the number of House of Representatives seats is capped at 435, as population grows, so does the size of each of the Congressional Districts. Amongst themselves, the Districts' populations grow unevenly, as can be seen in the Iowa map above; this illustrates why redistricting is necessary.

Closer to home, Congressman Bilbray's 50th District might shrink, geographically speaking, after redistricting; the population growth between I-5 and I-15 along the Route 56 corridor (roughly between the interstate shields on the map below) has been explosive:

However, any changes to Bilbray's District will depend, in large part, on population growth (or loss) in adjoining Districts. It will be very interesting to see how San Diego's population redistributed itself in the last 10 years when the Census data finally comes out.