Walnut, Diamond Bar Together in New Redistricting Maps

New congressional district boundaries approved Monday place Walnut in the same district as neighboring Diamond Bar.

The two communities, which share police resources and a school district, previously had different representation in Congress.

Walnut and Diamond Bar's new district will also include more of Hacienda Heights in L.A. County and more of Brea and Fullerton Orange County.

Walnut is currently represented by Rep. David Dreier (R-San Dimas), whose hometown of San Dimas has been placed alongside more San Gabriel Valley cities like Baldwin Park and West Covina.

The move puts Dreier's hometown in an area that tends Democratic, leaving him the choice of running against two fellow Republicans to the south in the new Walnut and Diamond Bar district or heading east.

Dreier's district previously encompassed much of the San Gabriel Mountains and cities like Arcadia, Walnut, Upland, and Rancho Cucamonga.

And the new district including Walnut also raises some questions for current Diamond Bar-based Rep. Gary Miller.

For Miller, who currently represents most of the area in the new district, the boundaries approved Monday may pit him against fellow Republican Ed Royce of Fullerton in 2012, but the new maps have also met with some challenges from party leaders.

Miller expressed dissatisfaction with the new maps in an interview with the Los Angeles Times Monday.

"Judges will make the decision…. What they've done to so many districts out there makes no sense," Rep. Miller told the Times.

The redistricting process, which occurs every 10 years, was done for the first time in state history by a 14-member citizen panel using demographic statistics and population data from the 2010 census to draw the new lines.

Commission Chairman Vince Barabba said at a press conference Friday that the group's goal was, in part, opening the political process to new challengers.

"For far too long, Californians have been frustrated by a legislative process that drew districts that primarily supported the re-election of incumbent legislators," Barabba said.

Commissioner Michael Ward — one of two commissioners to vote against the maps approved Monday — strongly criticized the commission's process and accused the final maps of breaking requirements of the Voting Rights Act. In one case, Ward cited Sen. Huff's Diamond Bar district as a case of gerrymandering.

"At the senate level, there is the Orange County hook that reaches from Cal Poly Pomona to Cypress, Stanton, La Palma," Ward said.

For Diamond Bar's state legislators, Sen. Bob Huff (R-Diamond Bar) and Assemblyman Curt Hagman (R-Chino Hills), the maps cut communities on the outskirts of their previous districts but keep both representing much of the same area.

Still, Rep. Miller stands to be most affected out of the Diamond Bar delegation by being placed in the same district as his fellow Republican incumbent Ed Royce in Fullerton.

While the plans pose a new challenge for Miller, the commission by crossing county lines to create a district including parts of Orange, Los Angeles, and San Bernardino Counties.

Both the city of Diamond Bar and the Four Corners Policy Committee, with representation from the city of Walnut, that would have split the city's current congressional district in three and put Diamond Bar in a San Gabriel Valley corridor, extending west to Monterey Park and Arcadia.

For a side-by-side comparison of the new and old districts, see the interactive maps created by the Los Angeles Times.