The Multnomah County Auditor’s Office has prepared and released the proposed 2011 Redistricting Plan. Redistricting is the process of redrawing established commissioner district boundaries to account for changes in population following the U.S. Census, which occurs every ten years. As a result of population changes, the lines are redrawn so that districts are of roughly equal population, as required by the Multnomah County Home Rule Charter.

Multnomah County’s Home Rule Charter requires the Auditor’s Office to prepare a plan to modify the district boundaries after each ten year census if the population of any Commissioner District exceeds 103% of any other Commissioner District. The plan must be presented to the Board by August 1 of the year following the census.

The results of the 2010 census showed that between 2000 and 2010, Multnomah County’s population grew 11.3%, from 660,486 to 735, 334. Because of that change, the ideal district size for the four County districts (county population divided by four) also increased from 165,122 to a new target population of 183,834. Had the populations of each of the districts grown at the same rate, redistricting may not be required. However, District 4-East, the fastest growing district, grew at 17.8% (from 165,144 to 194,609) while District 2-North, the slowest growing district, only grew at 4.9% (from 165,122 to 173,315); the resulting difference is 112.3%, which triggers the requirement to redistrict.

In reviewing the 2010 census data, auditors found that District 1 was over the target population by 2,356 and District 3 was under the target population by 2,614. To balance the populations between these districts, auditors proposed to move a portion of the District 3 boundary slightly westward to fully encompass the Sunnyside Neighborhood Association, thereby uniting a previously split neighborhood into one district. See the proposed plan for specific changes.

Similarly, auditors found that District 2 was under the target population by 10,519 and District 4 was over the target population by 10,775. To balance these districts, auditors proposed moving the eastern boundary of District 2 eastward to the boundary between the Portland and Gresham. Doing so united Parkrose Neighborhood Association, which was previously split between Districts 2 and 4. District 2 also picks up Argay Neighborhood Association and the portion of Wilkes Neighborhood Association that lies north of I-84. See the proposed plan for specific changes.

The resulting populations for the proposed districts are:

Population of Proposed Districts


2010 Population

Percent From Ideal Population

Number of Persons Over / (Under) Ideal

District 1-West




District 2-North




District 3-Central




District 4-East






Ideal Population



So how does redistricting actually work?

The Census counts all of the population where they live and reports it down to the geography of the block level, such as the block where you live. Blocks are aggregated together into block-groups and then into census tracts, so we can calculate how many people live in a block, block-group, census track and so on up to how many live in each Commission district. Generally we add population and geography to districts that are under-the-ideal population and subtract from districts that are over-the-ideal, until all four districts are approximately equal in population.

Can districts be changed or drawn in any way the Auditor wants?

No, the Charter (Section 3.15 Apportionment of Commissioner Districts) states, “The Auditor shall, as nearly as possible, retain the general geographical characteristics of districts established by this charter.” In essence, that retains the named West, North, Central and East Districts’ “general geographic characteristics” while complying with equalizing the population within the guidelines of the Charter and U.S. Constitutional requirements of “one-person, one-vote.”

Apportionment, reapportionment, and redistricting; what’s the difference?

In the strictest sense, apportionment and reapportionment refer to changing the number of districts allocated to a state or, in this case the county. For example, if Oregon gains enough population between 2000 and 2010 in relation to the other 49 states, we could gain a sixth congressional seat in the U.S. House of Representatives as a result of the 2010 apportionment or reapportionment. Multnomah County’s Charter has a section on apportionment of commissioner districts and in fact the number of districts has changed over the years. Because we will likely change the boundaries of the four existing districts, that action is technically called redistricting.

Multnomah County hasn’t always had four commissioner districts?

No, actually the number of commissioners has ranged from three to four to five and back to four as we are now. And, there haven’t always been districts; in the early days of the county and at various later times the commissioners ran at-large, or county-wide. The existing arrangement of having a Chair elected at-large and having four Commissioners elected by districts (resembling the current geography) was established in 1984 and approved by the voters in November of that year.

Are their other guidelines the Auditor uses to draw the districts?

Yes, per the Charter, the Auditor consults with the Elections Division, which in the past has recommended following simple recognizable boundaries, such as streets that are major arterials. In 1991 and 2001 the Auditor’s Office also considered the guidelines adopted by the state (ORS 188.010), which include: contiguity; equal population; existing boundaries; communities of interest; transportation links; not favoring any political party, incumbent or other person; and, not diluting the voting strength of any language or ethnic minority group. Not diluting voting strength is also required by the federal Voting Rights Act.

What about Gerrymandering and political favoritism?

First, the County Commissioners (and all of Multnomah County’s elected officials) are non-partisan, so there is no built-in temptation to gerrymander, or draw districts to favor a political party. Second, the Charter provision of maintaining the general geographic characteristics of the existing districts would preclude any significant change other than to attain population equality. And speaking of Elbridge Gerry, while a lot of people know what Gerrymandering is, not as many know that Gerry was active in the early days of forming our nation, was later Governor of Massachusetts (when the “Gerrymander” term was coined), and the fifth Vice-President of the United States (and the only one of the first five not to run for President; a downside of dying while V.P.).

Map of Commissioner Districts
Current Commissioner Districts (2001)
Map of proposed districts 1 and 3
Proposed changes to District 1 and District 3
Map of proposed district 2 and 4
Proposed changes to District 2 and District 4

Redistricting Documents