All you do is slow me down,
And I’m trying to get on the other side of town.”
– Jimi Hendrix, Crosstown Traffic
Jimi was never in Dexter, certainly not lately, but his lyrics sound like he’s tried driving through town during the afternoon rush.
Traffic through downtown gets clogged twice a day; during the morning school rush and then again in late afternoon for the home commute. As frustrating as it can be, the underlying cause is a good thing – a great community with excellent schools is what has drawn so many of us here.
But as with any complicated system such as a municipality, growth and development in one area stresses the next. It’s the chain reaction of progress. Now that we’re all here, we want to wash, flush and go places.
The growth in and around Dexter in recent years has taxed the infrastructure. The City Council is busy examining ways to update the water and sewer systems for area residents. Traffic flow is another task at hand our community leaders have begun examining. The City of Dexter hired the civil engineering firm of OHM to study downtown traffic and offer solutions. The results were recently presented to the City Council.
The stated purpose of the study was “to evaluate the reports of congestion and poor operations at the intersections of Baker Road and Main Street and Broad Street and Main Street in Dexter. The study provides analysis of the intersections using existing traffic volumes to determine which operational improvements would best serve the community’s immediate traffic needs. The study will investigate various operational alternatives to improve mobility in downtown Dexter for the near future.”
From traffic counts conducted last summer, the following data was collected:
- Morning peak period is between 7:30 AM and 8:30 AM.
- Afternoon peak period is between 4:45 PM and 5:45 PM.
- Main Street has an average annual daily traffic count (AADT) of approximately 11,700 vehicles (both ways).
- Broad Street forms a “T”-intersection with Main Street (Joe and Rosie’s is on the corner) and has an AADT is approximately 3,000 vehicles.
- Central Street (that hooks off Main around Monument Park) has an AADT of approximately 1,600 vehicles.
- Baker Road also forms a “T”-intersection with Main Street (Reed Barber Shop is on the corner) and has an AADT of approximately 5,400 vehicles.
The intersections were analyzed for the study according to the methodologies found in the Highway Capacity Manual, 2010 edition. The intersections were evaluated by the average delay experienced by vehicles. Factors involved in the computation included number of lanes and lane type, intersection controls (Stop sign or traffic light), traffic volumes, pedestrian activity, signal timing characteristics, speed limit, etc.
The average day during peak periods is used to determine Level of Service (LOS) values for each intersection movement as well as the intersection as a whole. LOS is expressed as a letter grade ranging from A through F. “A” represents the best conditions with very little or no average delay to vehicles. LOS “F” is the worst of conditions characterized by very large delays and few gaps of acceptable length. Many traffic safety professionals consider LOS “D” to be the minimum acceptable condition in an urban area.
During the study, numerous complications to the existing flow of traffic were observed. These disruptions included:
- Cars backing out of angled on-street parking on Main Street east and west of Broad Street.
- At Central Street, motorists are stopping on Main Street and allowing vehicles to turn left in and out.
- Numerous pedestrians in the downtown area are utilizing the pedestrian push-buttons at Broad Street to cross Main Street.
Each of the above factors causes additional delay along the corridor due to intermittent vehicle stopping and by knocking the traffic signals out of sync due to pedestrian actuations.
The report card below shows the intersection, the approach (NB = northbound, SB = southbound, etc.), the average delay per vehicle and the letter grade. Each approach to the intersection is graded separately. The “Int” column is the overall LOS grade of the intersection giving weighted accounting for car counts from each approach.
As seen overall, the intersection of Main Street and Broad Street operates at a LOS C in both the AM (the school rush) and mid-day periods, while it operates at a LOS E in the PM (the commute home) period. The intersection of Main Street and Baker Road operates at a LOS B in the mid-day and PM periods, while it operates at a LOS C in the AM period. The intersection of Main Street and Central Street operates at a LOS A in both the mid-day and PM periods, while it operates at a LOS B in the AM period.
The most concerning problem, as seen in the LOS report card, is westbound through traffic on Main Street in the PM peak period. Throughout the years, numerous efforts by the City have sought to improve westbound traffic flow in the late afternoon.
OHM’s recommendations to the Dexter City Council included the following:
- Improve synchronization of the two traffic lights.
- Change traffic lights to allow left turns when oncoming traffic is clear (yellow left turn arrow).
- Update the pedestrian clearance signals to the latest MDOT standards.
- Prohibit left turns from Central St. onto Main St.
- Prohibit left turns from the Dairy Queen parking lot onto Main St.
The bad news is, however, the implementation of these changes along with others will create only incremental improvements, barely noticeable to drivers. There’s just too much traffic going through a constricted corridor.
OHM concludes their study with this observation, “With these recommended operational changes, we believe that there will be minor improvements in traffic operations. However, this corridor will continue to remain problematic, given the heavy traffic flows seeking to pass through the heart of the City each peak commute period. To more effectively relieve the traffic pressure on the downtown, vehicles traveling through would need to be presented with a viable bypass route around the City.”
The project is just getting started and WeLoveDexter.com will pass along the development as it progresses.