HomeMy WebLinkAbout897 Route 28 Abstract Traffic Assessment Report for Site Plan Review on August 12, 2025Traffic Abstract
This traffic assessment evaluates the potential impacts of a proposed 26-unit multifamily
residential development at 897 Route 28 in South Yarmouth, Massachusetts, prepared for
Nantucket Sound Group, Inc., by Chappell Engineering Associates, LLC. The study
analyzes existing traffic conditions on adjacent roadways, including Pine Grove Road,
based on automatic traffic recorder (ATR) data collected in June 2025. Traffic volumes
were conservatively assessed without downward seasonal adjustments, per Cape Cod
Commission factors and MassDOT guidelines, revealing average daily volumes suitable for
the area. Observed vehicle speeds on Pine Grove Road were below the 30 mph posted
limit, with average speeds of 25 mph northbound and 24 mph southbound, and 85th
percentile speeds of 29 mph and 30 mph, respectively.
Sight distance evaluations at the proposed driveway indicate measured distances of 145
feet to the north (below the minimum stopping sight distance of 200 feet) and over 500 feet
to the south, assuming vegetation clearance within the sight triangle. Trip generation
estimates, derived from the Institute of Transportation Engineers (ITE) Trip Generation
Manual (11th Edition, Land Use Code 220 for Multifamily Housing - Low-Rise), project 180
weekday daily vehicle trips (90 entering, 90 exiting), 10 trips during the weekday AM peak
hour (2 entering, 8 exiting), and 13 trips during the PM peak hour (8 entering, 5 exiting).
These volumes represent a net reduction compared to the site's former use as a laundry
center (estimated using ITE Land Use Code 822 for Strip Retail Plaza <40,000 sf), and
account for potential long-term COVID-19 effects reducing peak-period commuting due to
increased remote work.
The projected traffic increases are minimal—equivalent to one additional vehicle every 12
to 15 minutes—and fall well below thresholds requiring a full traffic impact study under
Cape Cod Commission and MassDOT guidelines. Recommendations include vegetation
removal to achieve adequate sight distances, low-height landscaping (maximum 2 feet)
near the driveway, and installation of a STOP sign on the site driveway to ensure safe
egress. Overall, the development is expected to have negligible impacts on local traffic
operations and safety.
897 Route 28 Traffic Assessment Abstract for Site Plan Review on August 12, 2025