This variation affects on-road vehicle emissions, and, along with changes in meteorological conditions that govern dispersion, can cause dramatic changes in concentration of traffic-related pollutants, especially near major roads ( Gokhale, 2011 Kimbrough et al., 2013). Traffic activity is dynamic, varying with strong daily, weekly and seasonal patterns. Traffic activity encompasses the number of vehicles per hour on a road section, vehicle mix (fraction of different types of vehicles), and vehicle speed and acceleration. The methods and results presented in this paper can improve air quality dispersion modeling of mobile sources, and can be used to evaluate and model temporal variation in ambient air quality monitoring data and exposure estimates. Using either site-specific or urban-wide TAFs, nearly all of the variation in historical traffic activity at the street scale could be explained unexplained variation was attributed to adverse weather, traffic accidents and construction. The analysis shows the need to separate TAFs for total and commercial vehicles, and weekdays, Saturdays, Sundays and observed holidays. TAF-based models provide a simple means to apportion annual average estimates of traffic volume to hourly estimates. Five sites also provided vehicle classification. Annual, monthly, daily and hourly temporal allocation factors (TAFs), which describe the expected temporal variation in traffic activity, were developed using four years of hourly traffic activity data recorded at 14 continuous counting stations across the Detroit, Michigan, U.S. This study describes methods to improve the characterization of temporal variation of traffic activity. Accurate characterization of vehicle flows is critical in analyzing and modeling urban and local-scale pollutants, especially in near-road environments and traffic corridors. The temporal pattern and variation of traffic activity reflects vehicle use, congestion and safety issues, and it represents a major influence on emissions and concentrations of traffic-related air pollutants. The project began in 2021 and is expected to be completed this fall.Traffic activity encompasses the number, mix, speed and acceleration of vehicles on roadways. Work also is under way on East Montezuma Avenue. This year’s work will focus on the segment from Isle Royale Street to Pearl Street and include widening College Avenue to add a center left-turn lane, storm sewer improvements, and city sanitary sewer and water main replacements.
MDOT and the City of Houghton are investing about $9.6 million to rebuild 1.1 miles of US-41.
US-41 traffic must turn back on Shelden Avenue at Franklin Square. Local traffic is maintained along Montezuma Avenue to Shelden Avenue. The detour route begins on southbound M-26 at the Portage Lake Lift Bridge to Sharon Avenue and ends at MacInnes Drive. Northbound US-41 remains on its normal route, while southbound US-41 is detoured. The traffic configuration was expected to be changed in August, but more extensive excavation work for underground utilities has taken longer than expected, delaying paving and requiring the detour extension. The current detour around the Michigan Department of Transportation (MDOT) rebuilding project on US-41 in Houghton is now planned to remain in place until late October.