Conceptual Layout

The intersection of Lennon Road and Elms Road was included in the early preliminary engineering phase with support from the Genesee County Road Commission due to intersection operations. This intersection is a secondary analysis Tier Three intersection.

During the skim analysis, it was observed that there were two angle crashes and three head on left turn crashes over the 5-year period. These crashes resulted in zero fatalities, zero type A injuries, four type B injuries, and two type C injuries at the intersection.

The intersection of Lennon Road and Elms Road is an all-way stop control intersection. Stop signs and overhead flashing beacons are present for all approaches. Lennon Road runs east/west and is a twolane roadway with one lane in each direction. Elms Road runs north/south and is a two-lane road with one lane in each direction. Lennon Road intersects Elms Road at an approximately 45-degree angle. There is a business in the northwest quadrant. The other three quadrants are vacant immediately adjacent to the intersection. There is a self storage business just to the southeast of the intersection. An aerial of the existing intersection can be seen in the photo above.

An operational analysis of the no-build condition was completed for the intersection using the 2045 forecast traffic volumes. The results of the analysis for future no-build conditions reveals that all approaches operate at LOS C or better in the AM and PM peak hours, except for the Elms Road approaches in the PM peak hour which are LOS D.

The 95th percentile queue lengths were reviewed at the intersection and results showed that the approaches experienced a maximum queue length of 58 feet (3 vehicles) during the AM peak hour and 167 feet (7 vehicles) during the PM peak hour.

The operational results for future no-build conditions are presented in the table below.

A single-lane roundabout with an oblong shape is proposed at this location. The oblong shape would facilitate speed control at the skewed intersection without needing a large diameter roundabout. The inscribed circle diameter would be approximately 130 feet for the smaller dimension of the oblong shape and approximately 146 feet for the long portion. The roundabout would improve traffic operations and safety at this intersection. It is likely that a small amount of permanent right-of-way acquisition would be needed in the southeast intersection quadrant. A large overhead power pole is located in the northeast quadrant. This pole can most likely be avoided, but overhead power poles in the other quadrants may be affected. A concept design exhibit for this intersection can be found in the slide above.

An operational analysis of the roundabout (build) condition was completed for the intersection using Rodel software and the 2045 forecast traffic volumes. The results of the analysis for roundabout (build) conditions reveal that all approaches and movements at the intersection operate at LOS A during the AM and PM peak hours.

The 95th percentile queue lengths were reviewed, and results showed that all approaches would experience a maximum queue length of 0.8 vehicles during the AM peak hour and 1.7 vehicles in the PM peak hour for the single-lane roundabout design.

The operational results for future roundabout (build) conditions are shown in the table below.

A roundabout appears feasible at this location, assuming GCRC can acquire the limited right-of-way that may be needed.

An opinion of probable cost was developed for the single-lane roundabout. The probable cost is $1.36 million in year 2025 dollars. This cost includes a 20 percent contingency and 3 percent annual inflation.

Potential funding sources for this improvement could include regular road improvement funding or an earmark.

For a complete breakdown of the estimate please review the full report below.