Design Alternatives and Final Design
Seen on this page are the design alternative and chosen final design developed by the BETR Engineering team for the Roundabout Project. All designs were carefully considered for suitability in the areas of functionality, expense, safety, comfort, and general impact on the surrounding areas and community. The final design was chosen based on its lower overall cost to construct, higher safety for users, and lower expected driver discomfort.
Design Alternatives
Single Lane Alternative
This alternative consists of a single lane roundabout at the intersection of McConnell Dr. and Pine Knoll Dr. as well as another single lane roundabout at the I-17 exit ramp. To accomodate the bus pullout, eastern McConnell Dr. was realigned to allow for bus pull-offs on both sides of the roadway. A drawing for this design alternative can be found in the Photos & Drawings page of this site.
Double Lane Alternative
This alternative consists of a double lane roundabout at the intersection of McConnell Dr. and Pine Knoll Dr. as well as a median on western McConnell Dr. to direct all I-17 exit ramp traffic through the roundabout. To accomodate the bus pullout, eastern McConnell Dr. was realigned to allow for bus pull-offs on both sides of the roadway. A drawing for this design alternative can be found in the Photos & Drawings page of this site.
Bypass Lane Alternative
This alternative consists of a combination single-double lane roundabout at the intersection of McConnell Dr. and Pine Knoll Dr. with a bypass lane for traffic turning right onto Pine Knoll Dr. from McConnell Dr. as well as a median on western McConnell Dr. to direct all I-17 exit ramp traffic through the roundabout. To accomodate the bus pullout, eastern McConnell Dr. was realigned to allow for bus pull-offs on both sides of the roadway. A drawing for this design alternative can be found in the Photos & Drawings page of this site.
Final Design
The final design consists of a combination single-double lane roundabout at the intersection of McConnell Dr. and Pine Knoll Dr. with a bypass lane for traffic turning right onto Pine Knoll Dr. from McConnell Dr. as well as a median on western McConnell Dr. to direct all I-17 exit ramp traffic through the roundabout. To accomodate the bus pullout, eastern McConnell Dr. was realigned to allow for bus pull-offs on both sides of the roadway. To accomodate pedestrians and bicycle traffic, an extra wide shared use path was added on the north side of McConnell Dr. and the sidewalk was extended from the Milton Rd. bridge to Knolls Dr. The plan set for this final design can be found in the Photos & Drawings page of this site.
