SRPC Traffic Count Data

Every year, SRPC conducts traffic counts at 110 – 130 locations specified by the New Hampshire Department of Transportation (NHDOT) according to a 3-year rotating cycle of 329 locations in our region. We collect information on traffic patterns, traffic volume, and types of vehicles at each site, which NHDOT adds to a statewide database.

The NHDOT Traffic Bureau uses the data for Highway Performance Monitoring System reporting, project development, planning, and modeling. Other organizations use the information for decision making, since it provides tangible evidence of transportation system conditions. The data we collect is available on the NHDOT Transportation Data Management System website and, by request, directly from SRPC.

We have been conducting annual traffic counts since 1988. Staff members collect the data with automated traffic recorders (ATRs) and handheld manual recorders. ATR equipment remains in the field for at least five days, while handheld equipment is operated by staffers for between two and four hours at a time. SRPC conducts four main types of traffic counts: average daily traffic (ADT) volume, vehicle classification, vehicle speed, and intersection turning movement. Seasonal and axle correction factors are applied to the ADT data, which is then reported as annual average daily traffic by NHDOT.

The SRPC planning and data collection staff also conducts traffic count studies for member communities at locations not on NHDOT’s list. This service is free for dues-paying SRPC members and available by contract for non-dues-paying communities.

For more information or to request a traffic count, please contact Stephen Geis, planning technician.

2013 Traffic Count Data Report [PDF ]

2012 Traffic Count Summary [878 KB August 14, 2013]

2011 Traffic Count Summary [ ]

2010 Traffic Count Summary [3.01 MB PDF Jan 2011]