Three Mid-Columbia legislative districts grew enough from 2000 to 2010 that they will have to shrink once the state's Redistricting Commission finishes its work next year.
The commission published reports on the populations of the state's congressional and legislative districts once data from the 2010 Census was received Feb. 23.
The state overall grew by 830,419 people, and only one of the 49 legislative districts -- the 28th, covering part of Pierce County including Fort Lewis and McChord Air Force Base -- lost any population. That district lost 754 people during the decade, or less than 1 percent.
The five districts representing the Mid-Columbia in the Legislature all grew in population, but only three of them grew enough to exceed the average population of 137,236 per district that will make them all equal.
The 8th District, covering Benton County; the 13th District, covering Grant and Kittitas counties and part of Yakima County; and the 16th District, covering Walla Walla and Columbia counties, as well as Pasco, Finley and part of Kennewick, all have more than the target and will have to shrink in geographic size.
The 9th District, covering Adams, Asotin, Garfield and Whitman counties, and part of Franklin and Spokane counties; and the 15th District, covering Klickitat and Skamania counties and part of Yakima and Clark counties, both grew as well, but not enough to meet the target and likely will pull territory from other districts to make up the difference.
From 2000 to 2010, the 8th District grew by 29,185 people, or about 24 percent, putting the population for the district at 149,474, or 12,238 people over the target.
The 13th grew by 23,460 people, or 19.5 percent, to encompass 143,750 people. The 13th District will need to have 6,514 fewer people once redistricting is done.
The 16th District had the most growth in the Mid-Columbia and ranked third in the state for population growth, adding 34,542 people during the decade, or an increase of about 29 percent. That district's boundaries will have to be redrawn to include 17,594 fewer people by the 2012 elections when the new boundaries take effect.
The 9th District will have to gain enough ground to add 1,070 people to bring its 2010 population of 136,166 up to the redistricting target.
The 15th District will have to be redrawn to add 4,448 extra people. Its population is 132,788, according to census data.
The two congressional districts encompassing the Mid-Columbia also will have to shed people to make room for a new 10th district the state gained in the recent census.
The average population target for congressional districts is 672,454, but the 4th District, where Republican Rep. Doc Hastings represents the Tri-Cities, Yakima and Wenatchee, has 101,955 people too many, according to the Redistricting Commission report.
The 4th District grew by 119,508 people over the decade, or an increase of about 18 percent, for a population of 774,409 in the 2010 Census. It was the third-fastest growing congressional district in the state.
The 5th District, representing Spokane, Walla Walla and Adams counties and everything else east to the Idaho state line, grew by 68,705 people, or an increase of 10.5 percent, from 2000 to 2010.
The district represented by Republican Rep. Cathy McMorris Rodgers will have to shrink to include 51,155 fewer people.
The commission next meets March 29 in Olympia. The five members, including Chairwoman Lura Powell of Richland, have until Jan. 1, 2012, to approve a redistricting plan.
-- Michelle Dupler: 582-1543; email@example.com