Visible Layers:

Cities/Towns
A mix of both incorporated places (legal entities) and census designated places or CDPs (statistical entities). An incorporated place is established to provide governmental functions for a concentration of people. Places always nest within a state, but may extend across county and county subdivision boundaries. An incorporated place usually is a city, town, village, or borough, but can have other legal descriptions. CDPs are delineated to provide data for settled concentrations of population that are identifiable by name, but are not legally incorporated under the laws of the state in which they are located. Click on city/town name to highlight the boundary. Reference Source: U.S. Census, 2020.
County Commission Districts
For more information, see http://www.accg.org/. The districts were established in 2014, and were obtained from the Association of County Commissioners of Georgia (ACCG). Further processing was performed by the Office of Health Indicators for Planning (OHIP) of the Georgia Department of Public Health. History and role: In 1868 the state began creating the position of county commissioner to administer the general operations of the county. Today every county has a commissioner; many have a board of commissioners (BOC). As part of general county operations, the BOC must finance county programs. A BOC has the power to adopt ordinances, resolutions, or regulations relating to county property, county affairs, and the operation of local government (http://www.georgiaencyclopedia.org/nge/Article.jsp?id=h-589 ).
GA House Districts
Electoral districts from which State Representatives are elected. The Georgia Constitution requires not less than 180 Representatives apportioned by population from representative districts. Layer Source: https://www.legis.ga.gov/, Adopted 2023 – Effective for 2024 Elections.
GA Senate Districts
Electoral districts from which State Senators are elected. The Georgia Constitution limits the number to not more than 56 single member districts. Senate districts are apportioned based on population. Layer Source: https://www.legis.ga.gov/, Adopted 2023 – Effective for 2024 Elections.
Hospitals
Hospitals are the non-Federal acute-care inpatient medical facilities in Georgia. Click on the symbol to get the name. Reference Source: Georgia Hospital Association, 2021.
Interstates
Interstates are the freeways that are part of the Interstate Highway System in Georgia. The Interstate Highway System connects major cities within the United States. Click on the line to get the Interstate number. Layer Source: Esri, March 1, 2012.
Major Roads
Major roads are a combination of both federal and state highways connecting cities and towns. Click on the line to get the route number. Layer Source: Esri, March 1, 2012.
Perinatal Regions
The Perinatal Regions were established by the Department of Public Health in cooperation with the six teaching hospitals located in Atlanta, Albany, Augusta, Columbus, Macon and Savannah. The Regions reflect the hospital referral patterns for high risk pregnant women and newborns. Each of the six hospitals has a Regional Perinatal Center which has contracts with the state and receives funding to care for high risk pregnant women and infants as well as to train staff from other hospitals in perinatal care especially for high risk patients. Reference Source: Georgia Department of Public Health, March 2005.
ZIP Code
Established by the U.S. Postal Service for distribution of mail. Zip codes do not generally respect political boundaries or census areas such as tracts. Zip codes usually do not have clearly identifiable boundaries, often serve a continually changing area, are changed periodically to meet postal requirements, and do not cover all land area in the U.S. Layer Source: Esri, June 1, 2020.
ZIP Code Tabulation Area (ZCTA)
Zip Code Tabulation Areas (ZCTA’s) are a geographic entity made by the Census to approximate Zip Codes. USPS ZIP Codes identify the individual post office or metropolitan area delivery station associated with mailing addresses, and are not in fact areal features but a collection of mail delivery routes. ZCTA’s were created as areal features for use with statistics, change every 10 years, and have the same five-digit names as the Zip Codes they represent.

Base Layers:

Base layers are background information to provide contextual references for local-level maps. They are especially suited for tract-level maps and give real-world reference to maps you create in OASIS. There are six toggle-able (on/off) base layers:
Aerial Photograph
World Imagery provides one meter or better satellite and aerial imagery (ESRI).
Simple Street
Light Gray Canvas provides a neutral background with minimal colors, labels, and features allowing the choropleth maps to come to the foreground (ESRI).
Socioeconomic (SES) Vulnerability
Socioeconomic (SES) Vulnerability refers to the socioeconomic status domain/subset of the CDC’s Social Vulnerability Index (SVI) 2020. Socioeconomic vulnerability ranks census tracts within Georgia on 5 factors: below 150% poverty, unemployed, housing cost burden, no high school diploma, and no health insurance. Percentile ranking values range from 0 to 1, with higher values indicating greater vulnerability/lower socioeconomic status. Quintiles of the percentile rankings were used to create class breaks (Very Low, Low, Average, High and Very High SES Vulnerability). Keep in mind that “Very Low” SES Vulnerability equates to a High SES status. For more information see https://www.atsdr.cdc.gov/placeandhealth/svi/index.html. For data dictionary click here.
Street and Place Names
National Geographic World Map, developed by National Geographic and Esri, is designed to be used as a general reference map for informational and educational purposes (ESRI).
Street Map
World Street Map includes highways, major roads, minor roads, one-way arrow indicators, railways, water features, cities, parks, landmarks, building footprints, and administrative boundaries, overlaid on shaded relief for added context (ESRI).
Street Topographical
World Topo Map includes administrative boundaries, cities, water features, physiographic features, parks, landmarks, highways, roads, railways, and airports overlaid on land cover and shaded relief imagery for added context (ESRI).

Data Classification Methods:

Quantiles: splits the data into equal-sized groups, for example dividing all 159 counties into 5 groups from smallest number to largest. Roughly 32 counties will be in each group.
Natural Breaks (Jenks): looks for clusters in the data and groups similar values together, so each group has numbers that are more alike. For example, if mapping counts by county, Fulton may stand out by itself and be the only county in its group.
Which to use? That depends on what questions you’re trying to answer, and the distribution of the underlying data. Quantiles usually produces more compelling maps when using the Trendable Maps feature on OASIS. Jenks is useful to highlight natural patterns in the data and outliers. In sum:
Quantiles: Showing Overall Spatial Patterns Across Areas
Natural Breaks (Jenks): Highlighting Areas With Distinctly High or Low Values

Navigation Tools

Zoom Use scroll wheel; or Shift+click and drag mouse to draw zoom area; or use + - buttons.
Full Extent Full Extent: Select this button to see the entire map.
Pan Click and hold mouse.
Print Map: Click on this button to get a printable copy of the map in PNG format as it appears at the moment. Disable any pop-up blockers. Right click on the preview and you can choose to save, copy or print the preview. The preview can also be dragged and dropped to a folder or desktop.


V1.6 (7/30/2025)