- Why does COMPASS have two forecasts?
- How was the Trend forecast developed?
- How was the Community Choices forecast developed?
- How will the forecasts be updated?
- What is a Traffic Analysis Zone?
- What is a Demographic Area?
WHY DOES COMPASS HAVE TWO FORECASTS?
There are two forecasts: Trend and Community Choices. Both forecasts use the same regional growth control totals. For future population in the two-county region, the growth control established for the year 2030 was 825,000. This growth control was used to maintain some consistency when considering the two forecasts. Once the growth control total is reached in a first round allocation, adjustments cannot exceed the total. For example, if an area is assigned more growth, some other area(s) need to be reduced so that the 825,000 control total is not exceeded.
HOW WAS THE TREND FORECAST DEVELOPED?
COMPASS staff began developing the Trend forecast in 2002 starting with regional control totals for population, housing and jobs out to 2030 in five-year increments. The goal of this forecast was to allocate future growth based on prevailing residential patterns and densities. The primary factor in allocation was the amount of vacant and redevelopable land. Ada and Canyon County Assessors' files were used to develop an inventory of vacant and redevelopable land. Criteria for redevelopable land were created and reviewed with COMPASS' Demographic Advisory Committee.
Since Trend is based on current development (everything built to date) and on-going development (approved and preliminary development proposals), Trend will be adjusted each year to reflect changing patterns.
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 WILL THE FORECASTS BE UPDATED?
Trend Forecasts were updated in spring 2005 based on platting and permitting activity. These adjustments will be done annually.
Community Choices Forecasts were updated in spring 2005 based on platting and permitting activity. Similar adjustments and corrections may be made on an annual basis. When of a magnitude sufficient to affect recommended corridors or air quality issues, such adjustments may trigger an amendment to Communities in Motion.
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 July 2006, the next update to Communities in Motion will occur no later than July 2010. An update will move the horizon year forward to 2035, and control totals may be increased.
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 2005 the demographic areas near Meridian , Nampa and Caldwell were divided into smaller sections to allow for better analysis of specific growth areas within the cities.
