City of Parkland. Redistricting 2011 Final Report. October 28, Prepared by Scott L Burton GeoWeb Consulting Services

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1 City of Parkland Redistricting 2011 Final Report October 28, 2011 Prepared by Scott L Burton GeoWeb Consulting Services

2 Table of Contents Summary... 3 Background... 6 Methodology... 8 Conclusion Appendix P a g e

3 Summary City of Parkland Redistricting 2011 Pursuant to the City of Parkland s Charter, the City Commission is vested with the sole and exclusive authority to adopt a plan that specifies the boundaries of districts for the City of Parkland s City Commission districts subsequent to the decennial census of 2010, but at least 6 months before the qualifying period for the municipal election of The City Commission District Map adopted in this plan complies with the redistricting criteria and legal requirements of the U.S. Constitution; the federal Voting Rights Act of 1965; and related cases and statutes. The primary criteria used in creating the districts were to create districts nearly as equal as practicable with equal populations by contiguous boundaries as required in the City s Charter, Section 3.02 Per requirements in the City s Charter, Section 3.02, in August 2011, the City Commission retained an independent consultant, Scott L. Burton, of GeoWeb Consulting Services, to develop at least two redistricting plans for submission and consideration by the City Commission. In preparing the plans, the redistricting consultant adhered to the following guidelines: Population Equality equalize the population by forming City Commission districts designated by numbers 1-4 per City Charter, Section The goal was to develop plans that divide the City s population of 23,983 into four (4) districts with as close to a population of 5,996. Contiguous Boundaries - Use contiguous territory to form district boundaries per City Charter, Section Best Available Demographic Data Utilize U.S. Census Redistricting Population Data known as Public Law that depicts population counts at the smallest geographic level known as Census Blocks. Pursuant to the Equal Protection Clause in the 14 th amendment of the U.S. Constitution and the Voting Rights Act of Preserve Identifiable Communities of Interest -Avoid diluting the voting strength of protected communities within the City as set forth in the federal Voting Rights Act of Recognize that the City has a well-organized group of communities 3 P a g e

4 and neighborhoods, and therefore has established strong communities of interest; and thus, ensure that each community of interest is intact in a single district to the extent possible, while adhering to the law and applying and balancing traditional redistricting principles. Observe natural boundaries as district dividing lines. Draw districts as geographically compact as possible and practical to do so. Provide fair and effective representation for all citizens of the City, including racial, ethnic, and language minorities, and be in conformance with the requirements of the United States Constitution and Federal statutes. Pursuant to the City Charter, Section 3.02, 15 days prior to the first reading of adopting an ordinance on redistricting Commission districts, the City is required to have a redistricting workshop open for public input. On September 14, 2011, the City Commission held a Redistricting Workshop at which the consultant submitted for consideration four redistricting plans. During this Workshop, the City Commission approved two of the four redistricting plans with an addition request to develop a third plan in an attempt to further preserve communities of interest. On October 5, 2011, the City Commission meeting was held where three plans were presented to the City Commission for their consideration. Each redistricting plan complied with the redistricting guidelines stated earlier. City Commission reviewed and considered the three plans presented of which one was selected to be officially adopted at the next City Commission meeting. The official City Commission District Map is displayed in Figure 1. 4 P a g e

5 Figure 1. Adopted District Map for City of Parkland Commission Districts 5 P a g e

Background City of Parkland Redistricting 2011 The City of Parkland is located in the northwest section of Broward County to the east of the County s conservation areas and directly south of the Palm

Since that time, Parkland has grown significantly from a rural enclave to an affluent community where the City s 2010 population was 23,983.

6 Background City of Parkland Redistricting 2011 The City of Parkland is located in the northwest section of Broward County to the east of the County s conservation areas and directly south of the Palm Beach County boundary. Parkland was incorporated in 1963 with a population of approximately 100 residents. Since that time, Parkland has grown significantly from a rural enclave to an affluent community where the City s 2010 population was 23,983. Prior to the 2008 municipal general election, the City of Parkland s existing City Commission District map was divided into four commission districts as shown in Figure 2 below. Figure 2. City of Parkland s Commission District Map ( ) Pursuant to the City Charter, the 2008 Commission Districts had to be re-assessed as part of the reapportionment process every four years to determine if existing district boundaries are equal in population as practicable along with the opportunity to review new district boundary options. Using Broward County s Population Projections based 6 P a g e

7 on Traffic Analysis Zones (TAZ), the population for each district did not exceed 5% of the population mean 5,332 (21,328 population divided by four districts). However, based on the US Census 2010 population count for the City of Parkland, the individual districts exceeded the population equality criterion where an individual district should not deviate from the population mean by greater than 5%. as shown in Table 1. Table City Commission District and 2010 Census Population District Population Total Existing District (Census 2010) Population Deviation 1 % of Deviation from Mean 2 GOAL District 1 6, % District 2 5,704 (292) -4.9% District 3 6, % District 4 5,659 (337) -5.6% 1Population Deviation is number increments from the Mean. (+/- 5%) Total Mean 23,983 5,996 2 % of Deviation represents the Population in a Proposed District subtracted from the Mean or Average for a District divided by the Mean or Average As shown in Table 1, District 3 population count deviates by more than 6 percent based on the population shifts within the existing district when comparing them to the 2010 census population counts. There was also a concern expressed by the City Commission to redefine the commission district boundaries to further preserve communities of interest. Although communities of interest is not specified in the City s charter, it is a criterion recognized by the U.S Supreme Court and the Voting Rights Act of In short, the City Charter required that at least two district plans be developed that would meet the population equality criterion along with drawing commission district boundaries that reflect areas of common interest. 7 P a g e

Methodology The main criterion to determine population equality was to utilize the Public Law 94-171 to establish the individual Commission Districts to be nearly equal in population as practicable.

8 Methodology The main criterion to determine population equality was to utilize the Public Law to establish the individual Commission Districts to be nearly equal in population as practicable. Public Law , enacted in 1975, directs the Census Bureau to make special preparations to provide redistricting data containing the best available population counts at the smallest geographic area which are defined as Census Blocks. Census Tracts represent a larger geographic area that can display population, income, housing, and other information collected in the 2010 Census questionnaire. Census tracts are subdivided into block groups and census blocks. Census Blocks represent the smallest geographic territorial unit for which population data are available as shown in Figure 3. Figure 3. How to display Population information based on Geographic Hierarchies defined by the US Census Bureau as Census Tracts Census Block Groups Census Blocks PL Redistricting Data contains summary statistics on population derived from the 2010 Census questionnaire which can be displayed at various geographic levels. In 8 P a g e

9 the case of reapportionment, the Census Block represents the best data source available to create district boundaries that are nearly equal in population as practicable. Both the Census Block and PL contain a unique numbering code that allows the population information to be assigned to each geographic-based census block. Utilizing Geographic Information System (GIS) tools, the census blocks containing the population counts for each block allow the reapportionment process to group the census blocks to obtain population counts that are nearly equal as practicable. Grouping the census block population counts formulate the District boundaries for the City of Parkland. The following is a summary of how the districting process was used to create the redistricting plans. The basis for creating districting plans is source geography and source attributes. Source geography is geographic data, in this case, census blocks used for assigning units of census blocks into districts. Source attributes are defined as the population attributes associated with the source geography which is in this case, PL: Census Population counts. Using Environmental Systems Research Institute s (Esri) Districting Tool in ArcGIS, the census blocks were grouped together based upon total population to create the district boundaries. The goal was to create a district that met the nearly equal as practicable criterion. The nearly equal as practicable rule is determined by dividing the total population of Parkland by the number of election districts as adopted in the City Charter, in this case, four districts. The average or mean represents the ideal district population count. The City of Parkland s total population based on the 2010 Census questionnaire is 23,983 and four districts are required, by dividing 23,983 by four districts, the ideal population count for a district is 5,996. It would be difficult to create districts that have the ideal population of 5,996, so to make the district s population nearly equal as practicable, the recommended guideline is that a district population should not deviate more or less than 5 percent of the ideal population of 5, P a g e

10 In the development of the district boundaries, the absolute deviation of the mean is examined. The absolute deviation is the difference between a single election district s population and the ideal population of that district. If a district has a population of 5,749 and the ideal population district is 5,996, then the absolute deviation is 247 lower than the mean population. In other words, a district population of 5,749 would require an addition 247 persons to have the ideal population for that district. The deviation percentage variance is the difference between a single election district s population and the ideal population of that district, divided by the ideal population, expressed as a percentage. If a district has a population of 5,749 and the ideal population is 5,996, then the absolute deviation is 4.1%. It should be noted that the goal to maintain a population deviation of (+/-) 5% is a guideline to ensure that the City s Commission District Plan will not be challenged on the basis of population equality. The population equality is based on the Equal Protection Clause of the 14 th Amendment. As U.S Supreme Court Chief Justice observed in Reynolds v Sims, 377 U.S. 533, mathematical nicety is not a constitutional requisite when drawing legislative plans. All that is necessary is that they achieve substantial equality of population among the various districts. Id.at 579. Today, substantial equality of population has come to mean that district plans will not be thrown out for inequality of population if its overall range is less than ten percent unless there is proof of intentional discrimination within that range. Today, the Courts tend to review the overall range of 10 percent or less as opposed to the traditional 5% or less rule for deviation of mean for individual districts. In addition, the Supreme Court in Reynolds v Sims had anticipated that some deviations from population equality in terms of overall range or deviation of mean may be slightly over if it is based on legitimate considerations such as preserving communities of interest; e.g. Carstens v. Lamm, 543 F.Supp. at 91-93; Shayer v. Kirkpatrick, 541 F. Supp. at 934; LaComb v. Growe, supra; Riley,533 F. Supp. at 1181; Dunnell v. Austin, 344 F. Supp. at 216; Tawes, 253 F. Supp. at 735;Skolnick, 336 F. Supp. at P a g e

11 As shown in Table2, the City of Parkland is homogeneous in population in terms of racial breakdown (86% White; 7% Black: and 7% other), the communities of interest were largely defined based upon subdivisions where the goal was to provide equal representation for each subdivision by avoiding splitting up subdivisions where these communities would have have more than one City Commission representative while other communities would only have one City Commission representative. 11 P a g e

12 Table 2. Racial and Ethnic Breakdown based on Adopted Commission District Plan District Total Pop Hispanic or Latino Origin Not Hispanic or Latino Origin White Black or African American Asian Count % Count % Count % Count % Count % Count Perce nt % Hawaiian and Other Pacific Islander Count Perce nt % Count Other Perce nt % District 1 6, District 2 5, District 3 6, District 4 5, TOTALS 23,983 3,118 20,841 20,157 1,563 1, Source: 2010 Census Population, Public Law , U.S. Census Bureau 12 P a g e

The two driving forces behind the redistricting process were adhering to the population equality methodology along with preserving communities of interest as defined by the City Commission.

13 The two driving forces behind the redistricting process were adhering to the population equality methodology along with preserving communities of interest as defined by the City Commission. Therefore if the population equality for an individual district exceeded the 5% goal, the justification for slightly exceeding the threshold was to preserve communities of interest as identified by the City Commission during a redistricting workshop held on September 14, Esri s ArcGIS Districting Tool extension was used to create four (4) residential district boundaries using the Census Blocks to assign the population counts for each district while ensuring that the individual district population deviation percentage was not above or below (+/-) 5 percent and the overall range percentage of variance did not exceed 10 percent. Figure 4 shows the work flow process to create the district maps Figure 4. Esri s GIS Districting Process Applied to Generate the District Map Options 13 P a g e

14 Conclusion Three redistricting plans were presented to the City Commission as Exhibit A-C for final review and decision to approve one of the three plans which would be adopted as the official City of Parkland Commission District Map. Exhibits A- B - C are displayed in Appendix A. Exhibit B was adopted by the City Commission to be the City Commission District Map. Table 3 displays the population demographics associated with the adopted redistricting plan. Table 3. Population Equality: Population Deviation Count and Percent of Deviation from Mean EXHIBIT B District Population Total ADOPTED PLAN Population Deviation 1 % of Deviation from Mean 2 District 1 6, % District 2 5,662 (334) -5.6% District 3 6, % District 4 5,749 (247) -4.1% Total 23,983 Mean 5,996 Ideal Goal (+/- 5%) Mean Dev Pct Variance 3 4.8% Ideal Goal 5% Absolute Overall Range Overall Range Ratio Ideal Goal Range % Variance 6 11% 10% 14 P a g e

15 1 Population Deviation is number increments from the Mean. 2 % of Deviation represents the Population in a Proposed District subtracted from the Mean or Average for a District divided by the Mean or Average 3 Measures the average difference across all districts in the scenario as a percent (Absolute Mean Deviation / Ideal District Pop (Mean) 4 District with Greatest Population - District with Least Population 5 District with Greatest Population divided by District with Least Population 6 Absolute Overall Range / Ideal District Population (Mean) The goal was to ensure that the individual districts did not have a population greater than or less than 5,996 by a deviation of +/-5 percent. As shown in Table 3, District 2 had the greatest absolute deviation from the mean, 334 persons less than the ideal population district of 5,996. The deviation of percentage from the mean for District 2 was -5.6%. This district had the highest deviation from the mean, it was within the acceptable 5% guideline for obtaining equal population as practicable since it was important to ensure communities of interest were intact. Utilizing the prescribed methodology described in the previous section, three redistricting plans were submitted and presented to the City Commission for their review and recommendation. Based on the population equality criteria along with adhering to other federal guidelines such as compactness, contiguity, and communities of interest, by vote of 4 to 1, Exhibit B Commission District map was approved (refer to either Figure 1 in this document or in Appendix A). 15 P a g e

16 Appendix Redistricting Commission Districts Maps Exhibits A B C APPENDIX A 16 P a g e

17 Exhibit A 17 P a g e

18 Exhibit B 18 P a g e

19 Exhibit C GeoWeb Consulting Services 19 P a g e

City of Sacramento City Council 915 I Street, Sacramento, CA,

City of Sacramento City Council 915 I Street, Sacramento, CA, 95814 www.cityofsacramento.org Meeting Date: 1/18/2011 Report Type: Staff/Discussion Title: Council Redistricting Process Report ID: 2011-00044