Scenario Development
Last modified Tuesday, July 29, 2008 13:19
To look at ways to accommodate this continued growth, ARC has begun work on a new and exciting initiative that will allow public officials, citizens and developers to cooperatively plan with local and regional planners for alternative futures by choosing among a number of different scenarios. Envision 6 combines face-to-face collaboration with local elected officials and professional staff from each county in the region with the latest technology to take a “scenario-based” approach to deciding what the Atlanta region of the future can be.
What is Scenario Planning?
It is important for decision-makers to understand the options for changing development patterns of the past and the impact that our future growth will have on air and water quality, traffic congestion, housing, loss of trees and wildlife habitats. Though it is often challenging to obtain meaningful public involvement to consider growth and development before it occurs, it must be a priority.
Scenario planning helps us understand the interaction of growth decisions, local and regional plans. It can also provide governments with important information to help plan for potential growth. The region can benefit from the use of scenarios to educate us and explain how innovative and alternative development patterns can improve the quality of life throughout the region.
There are many different scenarios show how growth in the Atlanta region might occur in the future. All local governments in the Atlanta region have a Comprehensive Plan and a Future Land Use Map. In fact, ARC staff has combined all of the local Future Land Use Maps to create a picture of how growth in the region might look in the year 2030.
Will the Atlanta region look exactly like the growth planned by local governments? Probably not. Many factors, from energy costs to consumer preference, could impact a future scenario for the Atlanta region. Looking at other scenarios gives citizens and leaders insights into decisions that could improve our region as we grow. That is the purpose of scenario planning. Scenario planning offers alternative growth perspectives so citizens and leaders can consider and implement growth patterns with the greatest benefits for the region.
Scenario Process
In order to conduct to test scenarios in an efficient manor ARC contracted with Criterion Planners to create a custom application based INDEX PlanBuilder extension to ARCGIS. This extension allows for changes to be made to land uses in a Geographical Information System (GIS) and gives some results in real time. The land uses are “painted” with a paint that contains a land use with attributes of population, employment, and impervious surface. The paints also allows for the testing of different indicators to give directions of what the plan would mean both socially and environmentally to the region. Indicators used and their scores are provided in the appendix.
Paints were created based upon current land development densities within the Atlanta region and basic smart growth principles. Currently there are over 170 paints used in the four scenarios to get the most accurate representation of land use types and densities in the 13 county region. Paints included standard land use types, mixed use types of various degrees of densities, and vacant land types.
ARC tested four unique scenarios in 2005: Current land use; Land Use Acreage from the Mobility 2030 forecast; Local Future Land Use Map, and Local Aspirations. Each scenario land uses were rectified to the Traffic Analysis Zone (TAZ) boundaries and a five acre grid in a process called fish netting, so a land use polygon would be fully contained in a TAZ and be no larger than five acres. This process allowed the population and employment figures generated by the scenarios to be exported into ARC’s travel demand model.
The travel network used with the scenario testing was the Mobility 2030 network. This consistency allowed for equal testing of the transportation network with the variable being land use patterns.
Check back soon for final documentation
Learn more about scenario planning
See how other areas have used scenarios to develop transportation and land use policies.
