The lower Bear River drainage basin consists of about 730 square miles (1,890 km 2) in north-central Utah, north of and adjacent to Bear River Bay of the Great Salt Lake. An average of about 1,180,000 acre-feet (1,460 hm 3) of surface water entered the basin annually during 1960-71; most of this water entered in the Bear River and in canals diverted from the Bear River. Several streams develop from springs within the drainage basin and both the Bear and Malad Rivers gain considerably in flow within the drainage basin, mostly from ground-water discharge. An average amount of about 972,000 acre-feet (1,200 hm 3) of surface water leaves the drainage basin annually and flows toward the Great Salt Lake.

These are the Traffic Analysis Zones (TAZ) used in the Wasatch Front Travel Model. This dataset contains only basic geographic information about the zones.The Wasatch Front travel model region covers the urbanized portion of Weber, Davis, Salt Lake and Utah Counties and the portion of the Box Elder County from Brigham City South (Salt Lake City-West Valley City, Ogden-Layton, and Provo-Orem Urbanized Areas). The region is divided into 2,881 Traffic Analysis Zones (TAZ). TAZ boundaries are defined based on Census geographies (block, block group and tract). Care has been taken so that TAZ nest within Census tracts wherever possible in order for more direct matching with Census data. TAZ boundaries are also defined by major transportation facilities (such as roadways or rail lines), major environmental features (such as rivers), and with underlying land uses. The relative size of the TAZ was also a factor in deciding new TAZ boundaries if the zone size was large and the zone was thought to have a significant amount of socioeconomic activity. The size of TAZ varies from under 10 acres in the downtown to more than 100,000 acres in the mountain or lake zones. The average zone size is approximately 350 acres, which is a little over ½ square mile. Generally, TAZ in urban areas are smaller than in suburban and rural areas.

These are the Traffic Analysis Zones (TAZ) used in the Statewide Travel Model. This dataset contains only basic geographic information about the zones.TAZ boundaries are defined based on Census geographies (block, block group and tract). Care has been taken so that TAZ nest within Census tracts wherever possible in order for more direct matching with Census data. TAZ boundaries are also defined by major transportation facilities (such as roadways or rail lines), major environmental features (such as rivers), and with underlying land uses. The relative size of the TAZ was also a factor in deciding new TAZ boundaries if the zone size was large and the zone was thought to have a significant amount of socioeconomic activity. The size of TAZ varies from under 10 acres in the downtown to more than 100,000 acres in the mountain or lake zones. The average zone size is approximately 350 acres, which is a little over ½ square mile. Generally, TAZ in urban areas are smaller than in suburban and rural areas.There are currently 5 travel model spaces in Utah: Cache MPO (2), Dixie MPO (3), Summit (4), UDOT rural areas (0), and the combined WFRC/MAG MPO (1) model space. The model space indicators shown in parentheses above are coded in the Subarea_ID field. As travel demand model software requires that each TAZ be uniquely identified starting with the number 1, each model space has assigned its own unique TAZ identifier numbering sequence which is coded into the SubAreaTAZID field. However, this rule also applies to the statewide travel model, which is an aggregation of all the TAZs from the five model spaces into a single layer. In this statewide layer, the TAZID field is the unique identifier for the Utah Statewide Travel Model (USTM). CO_TAZID is the field used to link each TAZ to its socioeconomic data. It is a combination of the County FIPS number and a TAZ identifier within the county or from within an MPO model space.