Redistricting Archive

Collected here are various historical odds and ends relating to the decennial redistricting process.

A note regarding years: A particular vintage of Supervisorial Districts is often identified by just the decade of the decennial Census (f.e. 2000), though in fact it wouldn't have been adopted until the following year (f.e. 2001). You will see both versions of these years represented in these historical documents -- both versions represent the same "vintage".

Redistricting 2020

San Joaquin County encourages public participation in the redistricting process. As part of that effort, various tools and data are made available to the public as they become available. It is still far too early to do any real work on the 2020 redistricting, but a "mock" version of our interactive redistricting tool is available (using 2015 estimates) for those wishing to learn how the tool itself operates.

Interactive online application:

Mock Supervisorial Redistricting 2020

Expected Census 2020 Redistricting Timeline:

  • April 1, 2020 - Census Day
  • Around January, 2021 - Census Geography is typically available
  • No later than April 1, 2021 - P.L. 94-171 Redistricting Data to be delivered to the States
  • Betweeen April and September, 2021 - Redistricting Advisory Committee to be formed, then develop/propose/present/approve a new plan, then finally Board to adopt new plan by October 1, 2021.

Redistricting 2010

Interactive online application:

Supervisorial Redistricting 2010

Preparation:

2011-03-09 Initial Fact-Finding

2011-03-17 Racial/Ethnic Considerations

2011-04-04 Population Change 2000-2010 Per District

2011-04-04 Scenario #0 "Existing" (2001 boundaries, 2010 populations)

Initial Scenarios:

2011-04-06 Scenario #1 "Best Match"

2011-04-06 Scenario #2 "Minimize Displacement"

2011-04-06 Scenario #3 "Unify Manteca SD5 (Fails)"

2011-04-06 Scenario #4 "Unify Manteca SD3"

2011-04-06 Scenario #5 "Unify Manteca SD3 Clarify N/S Stockton SD1/2"

2011-04-06 Scenario #6 "Unify Everywhere Simultaneously"

Attempting an actual application of the "Delta in 3 districts" desired criteria:

2011-04-25 Scenario "Delta 3-Way Versus Criteria" 0.975%

Various alternative approaches:

2011-04-28 Scenario "4-28-11 Best Match A 0.107%" 04/28/2011

2011-04-28 Scenario "4-28-11 Best Match B 0.107%" 04/28/2011

2011-04-28 Scenario "4-28-11 Best Match G 0.087%" 04/28/2011

2011-04-28 Scenario "4-28-11 Fix All 6BGs 0.208%" 04/28/2011

2011-04-28 Scenario "4-28-11 JR 1/2 3BGs 2.804%" 04/28/2011

2011-04-28 Scenario "4-28-11 JR 1/2 6BGs 0.278%" 04/28/2011

A strategy was proposed to consider the largest outlier SD5 in isolation first, to better direct the remaining smaller adjustments if a preferred SD5 approach could be selected..

2011-05-04 Scenario "Fix Just SD5 - Existing"

2011-05-04 Scenario "Fix Just SD5 - Along Yosemite"

2011-05-04 Scenario "Fix Just SD5 - Backout Manteca"

2011-05-04 Scenario "Fix Just SD5 - Entire Delta"

2011-05-04 Scenario "Fix Just SD5 - Lathrop Delta"

2011-05-04 Scenario "Fix Just SD5 - Ripon Escalon"

Using the "Along Yosemite" approach for SD5 (see above), a full County-wide scenario:

2011-05-04 Scenario "20110504 0.699%"

More County-wide scenarios based off various SD5 approaches:

2011-05-11 Scenario "20110511A 0.405%"

2011-05-11 Scenario "20110511B 0.977%"

2011-05-11 Scenario "20110511C 0.514%"

Investigative scenarios for various strategy proposals:

2011-05-13 Scenario "Manteca 3-Way" 0.731%

2011-05-13 Scenario "South County 6" 0.240%

2011-05-13 Scenario "South County 7" 0.050%> (best known match to ideal)

2011-05-13 Scenario "Stripes" 0.830%

2011-05-13 Scenario "Unify Neat Lines" 1.447%

Presentation materials:

2011-06-03 Redistricting 2010 Criteria Poster For Public Meetings

Citizen submission:

2011-06-13 Scenario "Keep Cities Whole 7.235%" (Donald W. Parsons)

Alternative version of the 20110504 scenario:

2011-06-20 Scenario "20110504(mod20110620)(step2) 0.173%

The scenario approved by RAC (based off 20110504 work.. based off SD5 "Along Yosemite" work):

2011-07-12 Scenario "20110712(step3)" (As Later Approved) 6.147%

Final Adoption Process:

2011-07-14 Scenario "20110712(step3)" Color

2011-08-01 Scenario "Approved" (aka "Option A")

2011-08-01 Scenario "Manteca" (aka "Option B")

2011-08-01 Supervisorial Districts 2011 (Option A "Approved", sealed, pre-adoption, B&W)

2011-08-01 Supervisorial Districts 2011 (Option B "Manteca", sealed, pre-adoption, B&W)

2011-08-01 Supervisorial Districts 2011 (official, sealed, as adopted, B&W)

2011-08-03 Supervisorial Districts 2011 ("Adopted", Color)

2011-09-13 Supervisorial Districts 2011 ("Adopted" - Retitled, Color)

GIS data:

Supervisorial Districts 2011 (Shapefile)

Redistricting 2000

Preparation:

2001-04-06 Scenario "Existing Conditions" (1991 boundaries, 2000 populations)

Initial Scenarios:

2001-04-25 Scenario #1

2001-04-25 Scenario #2 (as later adopted)

2001-04-25 Scenario #3

2001-04-25 Scenario #4

2001-04-25 Scenario #5

2001-04-26 Scenario #6

Manteca unification strategy considerations:

2001-04-27 Scenario "Manteca in 1"

unification under SD2 was not considered due to contiguity/compactness constraints.

2001-04-27 Scenario "Manteca in 3"

2001-04-27 Scenario "Manteca in 4"

2001-04-27 Scenario "Manteca in 5"

Presentation materials:

2001-05-21 Redistricting 2000 Criteria

Citizen submission:

2001-05-25 Scenario "Bill St Clair"

Adopted:

2003-05-23 Supervisorial Districts 2000 (B&W)

Demographic details:

2002-12-19 Selected Census Values Per Supervisorial District

GIS data:

Supervisorial Districts 2001 (Shapefile)

Redistricting 1990

Supervisorial Districts 1991 Depiction

GIS data:

Supervisorial Districts 1991 (Shapefile)

Redistricting 1980

Supervisorial Districts 1981 Depiction

GIS data:

Supervisorial Districts 1981 (Shapefile)

Miscellaneous

What Is The "Minimum Majority" Measure?

Supervisorial District Changes 1981 - 2011