Saturday, June 4, 2011

State-by-State Block Level 2010 PL 94-171 Files Available for Download

We're making  state-by-state block level  2010 PL 94-171 files available for download.
The dataset uses Maptitude field name nomenclature and includes the same race and ethnic categories as the 2000 PL94-171 block files we posted at the start of the 2000 Census redistricting cycle.

Additional calculated fields for "any part" African American, American Indian, and Asian Americans are included with the 2010 version.

There are 17 zip files -- with two or more states combined and organized in no particular order.

These comma-delimited files are extracts from the Census Bureau files and  include most but not all multi-race and geographic fields.

As of June 1, 2011, we have used these files to develop statewide legislative plans for Virginia and South Carolina, as well as 35 local redistricting plans in a dozen states.

A nationwide point shapefile depicting 2010 group quarters blocks that we prepared for the Prison Policy Initiative is available here:

For Maryland redistricting, use the adjusted population data that reassigns the correctional population, released  by the Maryland Department of Planning.

Thursday, March 31, 2011

Redistricting Data Available for All States

The Census Bureau completed the release of the 2010 Census PL 94-171 redistricting file last week. We now have block-level databases loaded into Maptitude for Redistricting for the entire country.

Redistricting plans for local jurisdictions (our specialty) usually require block-level detail in order to deal with the multiplicity of factors involved in drawing election districts.

We've added a few more places where we have provided technical redistricting assistance (for community groups, politicians, or government entities) since our posted list last month. These include:




Chickasaw County
Oktibbeha  County
Webster County
City of Grenada


State Senate
US Congress

Northampton County
Sussex County
York County

City of  Norfolk
City of Williamsburg


Fremont County (Large v. Fremont)

In addition, we are providing ongoing technical support for a national project to end prison-based gerrymandering sponsored by the Prison Policy Initiative.

We conduct online live redistricting sessions via Plan maps are produced for Maptitude for the Web, Google Maps, or as Adobe PDF files.

Initial draft plans (with PDF maps and stats) can usually be produced in four hours or less for local jurisdictions. For community groups, an initial draft alternative plan is often all that is needed.

Rates are $125 per hour for government entities and litigation services, with discounts for non-profits. No community-based group is turned away due to inability to pay.

Sunday, March 27, 2011

Two Majority African American Congressional Districts Possible in Virginia

Two majority African-American voting age congressional districts can be drawn in Virginia, based on the 2010 Census.

The draft Congressional District 3 displayed below extends along the James River from Richmond and Central Virginia to Hampton on the north and Isle of Wight County on the south.  The draft district has a 50.03% any part African American voting age population and is 59% voting age minority.

The potential new South Hampton Roads/Southside Congressional District 4 is 50.14% 18+ any part African American and 55.5% minority voting age.

The Petersburg area is split between draft Districts 3 and 4.

As configured in the draft, both districts voted Democratic in the 2008 presidential contest and the 2009 gubernatorial race.

Like the current Congressional District 2, the draft majority-white District 2  is a waterfront district anchored in Virginia Beach. The district also includes the Eastern Shore and portions of Norfolk, Portsmouth, Suffolk, Chesapeake, and Hampton. All parts separated by water are connected by bridges.

The districts are drawn at the precinct (VTD) level and are close to zero deviation.

Thursday, March 24, 2011

South Carolina Set for Second Majority-Black District

A little over a year ago, we surmised that there was a good chance that a second majority African-American
congressional district could be drawn in the Palmetto State upon release of the 2010 Census. The South Carolina PL 94-171 redistricting file was released yesterday by the Census Bureau. The results are in. A second district can be created.

The map below shows a hastily drawn draft with downstate District 6 at 51.1 % any part African-American voting age and 55.4% minority voting age. Upstate District 7 has a 50.3% any part African-American voting age and 56.3% minority voting age. Both districts are close to zero deviation. The districts were drawn at the precinct (VTD) level.

Click map to enlarge

Download Shapefile (for plan drawers)

Monday, February 21, 2011

2011 Redistricting Underway

The 2010 Census has been released for about a dozen states and we're now producing redistricting plans and election-related analyses. We have imported the demographics into Maptitude for Redistricting software for these states. We'll convert the remaining states within hours of the Census Bureau release. Eight more states will be available this week. (see map)

Thus far, we've prepared draft plans or conducted analyses in the following places:


Somerset County


State House
State Senate

Bolivar County
Cleveland School District
Coahoma County
Grenada County
Scott County


Powhatan County
Prince George County

New Jersey

State Legislative Districts (prison population analysis)

South Dakota

City of Martin