Supervisors Hear Redistricting Report Based On Census 2010 Data
August 29, 2011
Supervisors Direct Staff To Prepare Final Redistricting Map
Preferred Final Redistricting Map
BACKGROUND: The United States Constitution requires a count every ten (10) years of everyone residing in the United States. Information from the Census is used to help determine where to locate schools, day care centers, roads and public transportation, hospitals and other facilities, and is used to assist in making decisions concerning business growth and housing needs. Census data is also used for geographically defining state legislative districts, a "redistricting" process that begins in the year following a census. The Census data allow County officials to realign supervisorial districts in their counties, taking into account population shifts since the last Census and assuring equal representation for their constituents in compliance with the "one-person, one-vote" principle of the 1965 Voting Rights Act.
The Placer County Board of Supervisors, at its Jan. 25, 2011 workshop, directed staff to assemble information on the redistricting process. Included below is background data and mapping. Click on the following links to see the respective maps and tables:
- Overall population changes by voting precinct
- Population Change by Jurisdiction 2000-2010 Map
- Population Change by Census Tract 2000-2010 Map
- Existing Supervisorial District Boundaries Map
- West Placer County Precinct Map (large scale)
- Municipal Advisory Council/Community Presentation Map A
- Municipal Advisory Council/Community Presentation Map B
- Municipal Advisory Council/Community Presentation Map C
- Municipal Advisory Council/Community Presentation Map D
- Municipal Advisory Council/Community Presentation Map E
The Board asked for analysis of the population changes that have occurred since 2000, the geographic context for those changes and the need to adjust supervisorial district boundaries to comply with state and federal law.
2000-2010 Overall Growth: As of 2010, the County of Placer has a population of 348,432 persons. This is an increase of 100,947 persons over the 2000 population of 247,485 persons. This represents a 40.79% growth rate for 10 years between census counts, or about 4.1% per year.
Between 2000 and 2010 there were a number of geographically-based changes to the County’s population that will cause adjustments in the supervisorial district boundaries. Notable changes include:
- Population reduction in the Tahoe Basin, with reductions in one census tract exceeding 25%
- Population increase in the City of Roseville equal to +49%
- Population increase in the City of Lincoln equal to +281%
- Population increase in the City of Rocklin equal to +57%
- Limited growth in the Town of Loomis (+2% growth)
- Limited growth in the City of Auburn (+8%)
- Reductions in growth in the unincorporated Auburn area (-5-10%)
- Limited growth in large unincorporated areas of District 5 (growth of about 100 person/year since 2000) excluding the Tahoe Basin
Important District Population Changes: Because it is essential to account for the “one-person, one-vote" principle contained in the equal protection clause of the U.S. Constitution, it is necessary to analyze population distribution with each decennial census. The review of the provided data has lead to some basic conclusions about population growth patterns and their affect on supervisorial district boundaries.
District 2 - District 2 grew by the greatest percentage by adding 55,295 persons. This yielded a 112% change in population; the majority of which occurred in the City of Lincoln. The City of Lincoln grew by 281%, by far the largest percentage of growth for any jurisdiction in Placer County. In addition to the largest change in population, District 2 also has the largest overall population with 104,880 persons residing within the District. The District 2 population currently represents 30.1% of the overall population of the County.
District 5 - District 5 has seen the smallest amount of overall growth with the addition of 1,008 persons over the past 10 years (an average of just over 100 persons/year). District 5 also has the smallest population with 49,097 persons and represents 14.1% of the overall population of the County. In addition, District 5 had two areas with population reductions: 1) Tahoe Basin and 2) Unincorporated Auburn area. The Carnelian Bay/Dollar Point area saw reductions of around 20%-25% likely due to fewer persons/household and a greater percentage of homes not serving as the primary residence when compared to 2000.
In order to achieve absolute parity between the five Districts with 0% deviation, it would be necessary to adjust the supervisorial district boundaries so that each district had a population of 69,686 persons. (Note: As discussed below the criteria being used by staff would allow a maximum of 5% deviation overall.) Table 1 depicts the amount of adjustment that would be required for each district if a 0% deviation was required.
Table 1
Population Adjustments by District – 0% deviation
|
BOS District |
2000 Population |
2010 Population |
Population Change for Parity |
|
Supervisorial District 1 |
52,378 |
74,190 |
-4,504 |
|
Supervisorial District 2 |
49,585 |
104,880 |
-35,194 |
|
Supervisorial District 3 |
46,377 |
53,251 |
+16,435 |
|
Supervisorial District 4 |
51,056 |
67,014 |
+2,672 |
|
Supervisorial District 5 |
48,089 |
49,097 |
+20,589 |
|
Total |
247,485 |
348,432 |
|
As noted above in Table 1, the majority of adjustments need to be made between Districts 2, 3 and 5. Districts 1 and 4 require limited or no changes.
Table 2 provides an overall summary of population changes, by each district, between 2000 and 2010.
Table 2
Population Growth 2000-2010 by BOS Supervisorial District
|
BOS District |
2010-Population |
2010-Percentage |
2000 Census-Pop |
2000-percentage |
% change 2000-2010 |
|
Supervisorial District 1 |
74,190 |
21.29% |
52,378 |
21.16% |
41.64% |
|
Supervisorial District 2 |
104,880 |
30.10% |
49,585 |
20.04% |
111.52% |
|
Supervisorial District 3 |
53,251 |
15.28% |
46,377 |
18.74% |
14.82% |
|
Supervisorial District 4 |
67,014 |
19.23% |
51,056 |
20.63% |
31.26% |
|
Supervisorial District 5 |
49,097 |
14.09% |
48,089 |
19.43% |
2.10% |
|
Total Population |
348,432 |
100.00% |
247,485 |
100.00% |
40.79% |
Figure 1 depicts the population density of the County with Western Placer County incorporated cities having the largest concentration by population.