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In April 2017, Premier Health and the University of Dayton came together to purchase and redevelop the 38-acre former Montgomery County Fairgrounds site. As anchor institutions, the partners are committed to a plan that authentically builds on their institutional missions and values, promotes economic development, and fosters a unique sense of place that serves broad community interests.

For 160 years, the fairgrounds site and the intersection of Stewart and Main Streets served as a community destination. There were also decades where this area was the economic and innovation engine for the city and region. The partners are now working to redevelop this important part of Dayton into a place that advances the missions of Premier Health and UD, boosts the economic vitality of the city and adds to the stability and health of the surrounding neighborhoods. As the former fairgrounds site redevelops into a vibrant place it will serve as an amenity for the adjacent neighborhoods. The site will be well connected to the existing neighborhood fabric and offer a variety of public spaces significantly improving this part of Dayton. The improvements to the adjacent public realm (i.e. Stewart Street and Main Street) will be felt by residents and businesses  alike.

It was important to the community, as well as to onMain, that the history of the site be preserved and celebrated. As part of a historic preservation strategy, Dayton History relocated horse barn No. 17 to Carillon Historical Park. The relocation of this barn presents an opportunity to aid in Carillon Park’s fulfillment of its master plan, and will bridge three themes; early Dayton, transportation and agriculture.

See the Site

This first step in preparing the site for redevelopment was to remove the existing structures and regrade the site. Full demolition of the other structures on the site began in the summer of 2019 and was complete by end of November 2019.

The drone footage shows a transition of the former fairgrounds before and after site preparation. The drone travels west along Stewart Street showing the site before preparation. As it approaches the intersection at Stewart and Main Streets, the video switches to show a view of the site after preparation, traveling north towards the Roundhouse and ends with a view of the site looking towards the south.

The Roundhouse dates from 1874 and was reconstructed in the 1950s (shown today in the photos above). The Roundhouse has the potential to serve as an important community gathering space within the site where all people feel welcome to enjoy this historic landmark.

Progress has been made to prepare the site for Dayton’s new imagination district. Some notable updates include: 19 buildings removed from the site, 340 tons of scrap metal recycled and 170 tons of barn foundation rescued.

The historical horse barn No. 17 is a stable built in the late 19th century and thought to be the oldest remaining structure at the former fairgrounds other than the Roundhouse. Barn 17 was dismantled as part of the onMain site preparation and has been reassembled at Carillon Historical Park by Dayton History where it tells the story of the Montgomery County Fairgrounds and the significant events that occurred on that site.

“As a result of the Fairgrounds to Future process, we envision a vibrant, pedestrian-friendly mixed-use development on the doorstep of downtown Dayton. A place where faculty and staff, doctors and researchers, neighborhood residents and community leaders can work, live and play. We see a place that sparks innovation and echoes Dayton’s can-do, creative spirit throughout history; a place with a distinctive identity and personality and a vibe that is open, welcoming, and inclusive for everyone.”

Mary Boosalis
President and CEO Premier Health (former)
Eric F. Spina
President University of Dayton

Frequently Asked Questions

1. Who is leading the onMain process?

OnMain is a collaborative venture between the University of Dayton and Premier Health. Leadership from both institutions will be involved throughout the development process, but a nonprofit development organization—OnMainhas been formed to lead day-to-day operations.

2. Why is this project important?

This is a once-in-a-generation opportunity to establish a vision that will serve the missions of the two anchor institutions, align development of the 38 acres with downtown revitalization, and serve the broader interests of the Dayton community.

3. This redevelopment will directly affect the surrounding neighborhoods, how were they involved in the process?

The planning process was deliberate, thoughtful, and inclusive. Neighbors and other stakeholders were invited to participate through workshops, focus groups, stakeholder interviews as well as through an interactive website with opportunities to provide input.

4. Has the larger public been involved in this project?

Yes, there have been interactive sessions held with the public where participants had the opportunity to learn more about the overall planning process and to provide insight. In addition to in person engagement, the community could participate using the project website. Public meetings focused on providing perspective on the public spaces and streets as well as how the private development might take shape.

5. Will the Roundhouse stay on the property?

It is the intention for the Roundhouse to be restored and incorporated as a unique space as a part of the development.

6. How long will this development take?

This is a long-term development project that will take 10-15 years to complete. The partners are committed to developing this site as a sustainable anchor for the long-term economic prosperity of the City of Dayton. This will require being extremely thoughtful to create a neighborhood that represents the best of Dayton as a city of innovation, entrepreneurialism, creativity, sustainability and inclusiveness.

7. What is so unique about this development compared to other developments that have been built in the Dayton region over the years?

This new neighborhood will be unique in the way people will live and work in an integrated way. It will be a platform to attract businesses and entrepreneurs to bring jobs and opportunities to Daytonians. The development will integrate environmental sustainability and wellness into all design elements. You can find out more on the Master Plan page of this site.

8. How will the community benefit from this development?

The community will benefit in many ways, including:

  1. Access to the neighborhood
  2. Access to and enjoyment of the public spaces
  3. Access to limited mixed income housing choices as part of the development; and
  4. Ability for local MBE/DBE businesses to compete for contracts through a Supplier Diversity Program.

In addition, the community may participate in a variety of ways:

  1. Community members serving on the Board of Directors of onMain
  2. A community-based advisory group
  3. Engagement on community projects, e.g. design workshop for public spaces

9. What type of housing is anticipated as part of development?

A range of housing choices are anticipated for onMain, primarily multi-family buildings with one- to two-bedroom units. (Larger units could be built they would be a small percentage of the total.)  Some rental and some ownership units could be provided. In addition, mixed-income housing is a key value of onMain leadership. There are several approaches to supporting mixed-income housing which include federally-qualified low-income housing. Encouraging the district’s workforce to live closer also helps supports the developments’ goal to promote sustainable, healthy environments.

10. What is the timeline for development?

At 38 acres, the onMain site is large. The partners are committed to working with partners as well as moving at a deliberate pace to realize the vision given the local economic conditions. It is anticipated that the first building will begin construction in 2025, and full buildout could take 15-20 years.

11. How can I learn more about the process and stay involved?

You can sign up for email updates on the Contact page and we will keep you informed of the progress of onMain.

12. What do I do if I am interested in investing and or developing on this property?

Please contact Buddy LaChance at

Implementation Team

Brian Heitkamp

Chief Executive Officer

Buddy LaChance

President and Chief Operating Officer

Board of Directors

Kathleen Carlson
, Chair. Retired Vice President of Captrust Financial Advisors
Joann Ringer, Treasurer and Secretary. Chief Administrative Officer, Premier Health
Andrew Horner, Assistant Treasurer. Executive Vice President for Business and Administrative Services, University of Dayton
MaryAnn Recker. Vice President and General Counsel, University of Dayton
Rick Omlor, Chair. Retired President/CEO, YSI Inc.
Helen Jones-Kelley. Director, Montgomery County Alcohol, Drug Addiction and Mental Health Services (ADAMHS)
Joe Geraghty. Executive Director, Dayton-Montgomery County Port Authority

Institutional Leaders

Michael Riordan. President and CEO, Premier Health
Eric Spina. President, University of Dayton

Fairgrounds Redevelopment LLC

Darlene Weaver. Provost and Executive Vice President of Academic Affairs, University of Dayton
Andrew Horner. Executive Vice President for Business and Administrative Services, University of Dayton
Craig Ganger. Executive Vice President and Chief Financial Officer, Premier Health
Joann Ringer. Chief Administrative Officer, Premier Health

Advisory Committee

Ted Bucaro. Executive Director, Government and Regional Relations, University of Dayton
Gwen Buchanan. Carillon Neighborhood President
Ken Clarkston. President, Rubicon Park Business Association
Dave Judson. CEO, JJR Solutions
Sharon Howard-White. Director, Community & Government Relations, Site Communications Premier Health
Steven Gondol. Planning and Community Development Director, City of Dayton
Brady Kress. President and CEO, Dayton History
Katie Meyer. President, Downtown Dayton Partnership
Belinda Matthews-Stenson. Vice President, Business Inclusion, Dayton Area Chamber of Commerce
Nikol Miller. Community Relations Manager, Greater Dayton RTA
Nancy McHugh. Director of the Fitz Center, University of Dayton
Mike Parks. President, The Dayton Foundation
Bob Ruzinsky. President and CEO, Greater Dayton RTA
Julie Sullivan. Exec. Vice President of Regional Development, Dayton Development Coalition

Consultants and Other Partners

Planning NEXT
City of Dayton
CityWide Development
McBride Dale Clarion
Ninigret Partners