Project Summary

The County Engineer is proposing to relieve congestion and improve safety at the intersection of Mad River Road and Alex Bell Road by eliminating the four-way stop and constructing a one-lane roundabout.  The project will build a roundabout with an outer diameter of 130 feet.   Pavement width in the roundabout will be 18 feet.  The center island will be landscaped with trees, shrubs, and flowers.  Construction is scheduled to begin in April of 2022 and last approximately four months.   The intersection must be closed to traffic during construction, and detours will be posted.


ODOT RESOURCES (one-page brochures)

As of 2020, more than 200 roundabouts have been constructed Ohio.  The Ohio Department of Transportation (ODOT) has developed a series of brochures to assist drivers in understanding and navigating this increasingly common intersection type.


American Structurepoint, Inc. is the engineering firm in Columbus, Ohio, selected by the Montgomery County Engineer to design the Mad River-Alex Bell roundabout.  American Structurepoint has created video tutorials available on YouTube to visually demonstrate key principles of driving through roundabouts.

  • How to Drive a Roundabout – Visual Guide


Systematic, well-designed, and implementable research is often the most effective starting point for solving the many problems facing state departments of transportation (DOTs). Highway problems of local or statewide interest can be studied by state DOTs individually or in cooperation with in-state universities and engineering experts. However, the accelerating growth and complexity of highway transportation systems has resulted in identification of problems of common interest to highway authorities nationwide. These problems of national interest are best studied through a coordinated program of cooperative research.

Recognizing this need, in 1962 the American Association of State Highway and Transportation Officials (AASHTO) initiated an objective national highway research program using modern scientific techniques called the National Cooperative Highway Research Program (NCHRP). Funded by the participating member states of AASHTO, NCHRP also receives critical technical support from the Federal Highway Administration (FHWA) of the United States Department of Transportation.

The Transportation Research Board (TRB), part of the National Academies of Sciences, Engineering, and Medicine, was selected by AASHTO to administer the highway research program because of TRB’s experience with modern research practices and recognized objectivity. TRB is uniquely suited for this purpose for several reasons: TRB maintains an extensive volunteer committee structure from which authorities on highway transportation topics may be drawn; TRB maintains avenues of communication and cooperation with federal, state, and local governmental agencies, universities, and industry leaders; TRB’s relationship to the National Academies provides assurance of objectivity; and TRB employs full-time staff specialists in highway transportation practices and research project management to effectively bring the research findings directly to end-using agencies.

Should you have questions regarding the project, please contact Richard Splawinski of the Montgomery County Engineer’s Office at (937) 496-6510 or .