Census population data will spur redistricting
The U.S. Census Bureau released the headcounts for Idaho cities and counties Tuesday, information wil that fuel changes to the state's political map. The state population grew 21 percent from 2000 to 2010, with the state's four largest counties fueling that growth.
The census data will be used in Idaho's redistricting process, which starts in June. A six-member commission will redraw the state's 35 state legislative districts and two constitutional districts. Republicans and Democrats will each get three seats at the table, with the leaders of the state parties and the partisan leaders in the Idaho House and Senate each picking a person for the commission.
Senate President Pro Tem Brent Hill, R-Rexburg, said he and the other Republicans who get to pick a commissioner could pick all three together. He said they've exchanged applicants' resumes and have discussed some redistricting strategy. The state GOP also has a redistricting task force that's researching the issue.
The Idaho Democratic Party has a request out for potential commission members and support staff on its website. “We are talking to interested Democrats who want to serve on the redistricting committee,” said Shelley Landry, the party's executive director.
Areas of strong Republican support showed growth. Canyon County in southwest Idaho had a 43 percent population increase, the second highest among all counties. Boise, which claims nine Democrats in the Legislature and the largest city in the state at 205,000 people, grew at a slower than surrounding cities. Neighboring Meridian more than doubled in size and added twice as many people as Boise.
Southeast Idaho's Bannock County, which elected another four Democrats from Pocatello, added people at half the rate of the rest of the state.
The redistricting commission will also need to redraw Idaho's two congressional districts. The state didn't grow enough to add a third representative in Congress in 2012, but Rep. Raul Labrador's 1st District, which stretches from north Idaho down to the southern border, including Canyon County and part of Boise and Ada County, now has 116,278 more people than Mike Simpson's 2nd District, which serves most of Boise as well as southeast Idaho. That population change means Simpson could well end up serving more of Ada County.
The redistricting commission will need to draw up 35 districts, splitting Idaho's 1.5 million people into sections of slightly less than 45,000. State law, the U.S. Constitution, and several court cases set some guidelines for what the districts can look like. Districts can vary in population by up to 10 percent, and the commission is supposed to keep counties intact and avoid gerrymandering, which is carving out strange districts to benefit a certain party or population.
Republicans have said one priority for redistricting could be making sure a car could drive from one end of a district to another without traveling into another district or state. The way cities and counties are split up or grouped together can affect which party or which type of candidates could succeed in elections. The new districts should be in place for the 2012 elections.
Based on the census data, 15 districts' populations are now far enough below the 45,000 mark that their land area would need to grow, including four Boise districts and the four districts serving north central Idaho from Moscow to McCall and south to New Plymouth.
Conversely, eight districts have seen a boom in population and could shrink. That includes six districts west of Boise and two in eastern Idaho.
The redistricting commission should start meeting in early June and will hold meetings during a 90-day span. Any decision on drawing district lines must be approved by at least four of the six commissioners, which would require bipartisan support.
The chart below lists Idaho counties and cities by size and population growth, as well as all 35 legislative districts by size and their ratio to an average district size.