The West Chester Township Board of Trustees at a May 1, 2019 Special Meeting heard from Greg Wilkins, Butler County Engineers Office (BCEO), regarding the increased cost of the Diverging Diamond Interchange (DDI) improvement of the UCB/I-75 interchange.

The project scope began in 2014 and the BCEO guesstimated the cost at $14M. Since then the price increased to nearly $20M which was a low bid from John R. Jurgensen for transformation of the interchange. The Board approved the bid and the project is moving forward.

So why did your Board of Trustees approve the project and why did the cost increase so much over five (5) years?

The project was approved for two primary reasons:

• The price of the DDI is only going up! This is due to the new gas tax, which is making travel more expensive, but is putting more ‘road money’ into local jurisdictions for road improvements. This creates supply and demand issues with construction competition (more work, same number of companies doing the work). Also, with the economy at essentially full employment, labor costs are rising, plus normal inflation over the last five years has impacted the cost. Remember, in 2014 when the BCEO first looked at the project, the $14M was only a guesstimate.

• The Union Centre Blvd area has momentum, i.e. development is continuing at a great pace. With almost 20% of the commercial land still to be developed, this Trustee did not want to discourage development because of “traffic jams”! Today, almost 50,000 vehicles per day use Union Centre Blvd. To put it in perspective, 150,000 vehicles per day travel north and south on I-75. So, Union Centre Blvd, on and off the highway, handles about 1/3 the traffic of the interstate! Within five years, I believe Union Centre Blvd will be the busiest road in West Chester.

For those of you interested in the specific details of the $6M DDI price increase, they follow.

As previously mentioned, in 2014, the BCEO guesstimated the project would cost $14M and they thought the project would be out for bid by November 2017.

In March 2015 the scope of the DDI project was created. In May 2015 a Request for Quote (RFQ) went out for an engineering design consultant and the Design Consultant was selected by BCEO.

Coincident with the Design Consultant RFQ, the BCEO started looking into the various studies that state and federal agencies required. Unfortunately, these studies delayed the bid process for a year and a half for the following reasons:

• Since the Divergent Diamond Interchange design was new to Ohio and there were questions of the designs’ safety, the state required a FULL Interchange Modification Study (IMS). This mandate took a lot more time.

• Other interchange designs like the Partial Cloverleaf Interchange had to be studied to compare safety, cost and traffic movement.

• The impact of using traffic signals to ‘meter’ traffic from the on ramps to I-75 had to be studied.

• Finally, ODOT had a new software modeling program for traffic count estimates around the interchange that had to be used.

Due to the year and a half delay, in February 2019 the price of the DDI Improvement was revised to $16.5M and then $17.3M.

In March 2019, West Chester Trustees traveled to Chicago to present Township finances to Moody’s Investment Services, in order to get the best bond rating possible. We achieved our goal and got their highest Aaa rating and a $14M bond was created. 

By April 2019, BCEO updated the price to $18.5M. This was done because any bid that was 10% over the estimated (revised) price had to be REJECTED by law! Eighteen bid packages were sent out with only three (3) responses. John R. Jurgensen Construction was the low bidder for the project, with a bid 7% over the $18.5M, or just under $20M! Check out this update from Greg Wilkins, Butler County Engineer.

The transformation of the interchange will take place on the existing bridge deck and will include extension of the highway ramps. Nearly all of the work – over the next two construction seasons – will take place without complete closure of the bridge or road. A four-day closure of the bridge will be necessary at some point and will be planned for a weekend.

Check out this link for a West Chester Storyboard on the new DDI,

Here’s a great video illustration of a Diverging Diamond Interchange at I-75 and University Parkway in Florida.