Scenario Planning

OVERVIEW

Scenario planning is a strategic planning method used to develop and analyze long-term plans. Typically, several land use options are considered and objectively evaluated against quantifiable criteria (e.g., projected population, dwelling units, employment). Scenario planning is more flexible and allows for more creativity than conventional planning, especially in creating solutions that are not initially obvious. The following is a summary of two scenario planning software programs that have been used recently for regional planning and general plan updates in California.

I-PLACE³S

I-PLACE3S is a web-based modeling platform for scenario planning. It can evaluate how alternative development approaches or transportation investments may impact a number of indicators, including transportation patterns, energy usage, cost efficiency, and climate change. I-PLACE3S analysis is conducted through a web-based map display. This strong visual component and interactivity supports scenario development and testing by non-technical users in settings such as public workshops, as well as in more technical settings.

UPlan

UPLAN is a model that projects urban growth by using several land uses as inputs. The model relies on fine-grained grid data that represent existing urban, local general land use plans, and all other relevant natural and built features that define the model. It is deterministic and rule-based, so as to be transparent to the user. The UPlan model works based on the following assumptions:

• The population growth can be converted into demand for land use by applying conversion factors to employment and households.

• The new urban expansion will conform to city and county general plans.

• Cells have different attraction weights because of accessibility to transportation and infrastructure.

• Some cells, such as lakes and streams, will not be developed. Other cells, such as sensitive habitats and floodplains, will discourage new development.