Frequently Asked Questions about COMPASS Forecasts

1. Why does COMPASS have two forecasts?
2. How was the Community Choices forecast developed?
3. How was the Preservation Forecast developed?
4. How will the forecasts be updated?
5. What is a Traffic Analysis Zone?
6. What is a Demographic Area?

WHY DOES COMPASS HAVE TWO FORECASTS?
There are two forecasts: Community Choices and Preservation. Community Choices is based on the regional growth control total of 1.046 million population with a horizon year of 2035. The allocation of this forecast represents a reasonable and rational approach to where future growth will occur. This allocation was developed through a land use model (UPlan) and the collaborative review by land use and transportation agencies.

HOW WAS THE COMMUNITY CHOICES FORECAST DEVELOPED?
In late 2005, a different demographic scenario was developed out of scenarios prepared during the October 2004 and February 2005 workshops and meetings with elected officials. Community Choices is a vision for the future with more growth concentrated within existing areas of impact, some transit level densities along key corridors such as the railroad. It provides for open space between communities.

In December 2005, the COMPASS Board approved Community Choices as the preferred growth forecast to be used in Communities in Motion, the regional long-range transportation plan. Community Choices does not reflect the way the region has been growing, instead it incorporates a vision for how we would like to grow.

Each year COMPASS staff will monitor growth in the valley and compare the “reality” of Trend against the “vision” of Community Choices. If the vision is being implemented by the actions of local governments in Ada and Canyon Counties, the Trend forecast will begin to move closer to the patterns shown in the Community Choices forecast.

HOW WAS THE PRESERVATION FORECAST DEVELOPED?
COMPASS developed the Preservation forecast by reviewing local land use plans to quantify a buildout population and jobs. This forecast will be used for corridor preservation, is not constrained by the 1,046,000 population forecast adopted by the COMPASS Board, and is not an official forecast for air quality conformity. It can serve in determining committed demand and service levels for Blueprint for Good Growth. The Preservation forecast was developed by developing a regional land use map, determining built conditions and unbuildable land, and assigning density factors by land use categories. This effort is not intended to judge or comment on the merits of a jurisdiction’s comprehensive plan. There is no timeline for this forecast but is rather a quantification of the buildout of local land use plans?

HOW WILL THE FORECASTS BE UPDATED?
The Preservation Forecast was completed in fall 2009 and will be updated annually based on the development patterns and changes to local land use plans. Community Choices Forecasts were updated in winter 2010 based on a variety of economic, political, demographic, and geographic conditions which influence growth and development patterns. COMPASS will produce an annual monitoring report that “…summarizes progress toward achieving alternative transportation and desired land use objectives. The report will provide information relevant to determining the need to amend or update the plan.”

In addition to the annual monitoring and adjustment process, Communities in Motion is required to be updated at least every four years. With adoption slated for August 2010, the next update to Communities in Motion will occur no later than August 2014. The update will move the horizon year forward to 2035, and control totals may be revised.

COMPASS reserves the right to make these adjustments, amendments and updates as needed to fulfill its legal obligations under federal regulations. Any forecasts developed by COMPASS are intended for transportation and air quality purposes. Any other use is incidental, and at the user's own discretion.

WHAT IS A TRAFFIC ANALYSIS ZONE?
A Traffic Analysis Zone (TAZ) is a special area delineated by state and/or local transportation officials for tabulating traffic-related data. The boundaries typically follow physical features such as streets, rivers or canals and are updated as part of the decennial census. There are over 500 TAZs in Ada and Canyon Counties. TAZs vary in size from a few blocks to several square miles. The former are typically found in downtown areas, while the latter are more typical in rural areas. Nearly all metropolitan planning organizations such as COMPASS use TAZ geography to analyze future transportation needs.

WHAT IS A DEMOGRAPHIC AREA?
Demographic Areas are an aggregate of multiple TAZs. Since there are so many TAZ's, demographic areas provide a conceptually easier way to view data collected at a TAZ level. Demographic areas do not match either city limits or area of impact boundaries and are generally updated every ten years when the TAZ boundaries are updated. Because city limits and city area of impact boundaries expand continuously, demographic areas provide a good geography by which to analyze growth trends in a given area over time. In 2008 the demographic areas were divided into smaller sections to allow for better analysis of specific growth areas within the cities.