“The traffic projected in 1991 for Mason-Montgomery Road just north of the southbound exit ramp for 2020 was 32,000. In 2002, the traffic count was 48,000.”

A rural Warren County was the foundation for the newly constructed I-71

The newly-constructed I-71 opened in Warren County in the mid-1960s. It included an interchange connecting it with the intersection of Fields-Ertel Road and Mason Road/Mason-Montgomery Road on the Hamilton County and Warren County boundary. The interchange was designed with the exit ramps emptying onto Mason Road in Hamilton County and Mason-Montgomery Road in Warren County and the entrance ramps to I-71 running off Fields-Ertel Road. In the former rural setting, this functioned quite well.

As the area developed in the 1970s and 1980s, improvements were needed. A traffic signal with left turn lanes at the Fields-Ertel Road-Mason Road/Mason-Montgomery Road intersection was constructed in 1984. Traffic signals at the exit ramps were added later. When Kings Auto Mall was built in 1986, an access management plan was created by public agencies in Warren County and Hamilton County with the Ohio Department of Transportation (ODOT) for future access points. Warren County developed a similar plan for Mason-Montgomery Road.

P&G fuels growth

Procter & Gamble short listed a 210-acre site on Mason-Montgomery Road as a site for a new $280 million pharmaceutical research center in 1991. That is when then-Governor George Voinovich provided many incentives to attract this significant high-quality research center to Warren County. The investment included $15 million in Federal/State highway funding to widen I-71 in the area of the interchange and the entrance and exit ramps and $7 million in loans for improvements of local roads benefiting the P&G development. The loans were paid back with revenues derived from a tax increment financing (TIF) district created on the P&G property.

Procter & Gamble’s research center became the catalyst for development and business growth when it opened in 1996. Mason particularly benefited, growing from a population of 11,000 in 1990 to over 33,000 in 2010. Other high tech industry also has come to Deerfield Township and the City of Mason in this period. Commercial and retail expansion following this trend has further increased business activity in the interchange area.

Actual traffic volumes outpace projections

The traffic projected in 1991 for Mason-Montgomery Road just north of the southbound exit ramp for 2020 was 32,000. In 2002, the traffic count was 48,000. Frequent travelers of I-71 have identified the Fields-Ertel Road Interchange for its backed-up northbound off-ramp. The back-ups stemmed from too short of a deceleration lane and no space for cars to collect on the ramp while waiting for the light. Safety concerns were high regarding this deficiency. The network of roads, in the area around the interchange has also caused concern, and alternatives for a sequence of projects for improvement were developed.

ODOT identified the Mason-Montgomery Road and Fields-Ertel Road Interchange as a safety and congestion hot spot. The 2006 Hot Spot Freeway List included the segment of I-71 between mile marker 18.00 at the bridge over Kemper Road and mile marker 19.91 at the northbound on-ramp from Fields-Ertel Road, as having the 58th highest number of crashes on the interstate system in the state with 359 recorded crashes. The interchange improvements in this area were deemed necessary for improving safety for the traveling public and reducing the chronic congestion on both the interstate and the local roadways.

ODOT further identified that the main line of Interstate 71 and both the on and off ramps met or exceeded design criteria. Both exit ramp intersections with Mason-Montgomery Road were unable to hold a sufficient number of vehicles, and there was a general decline in the level of service and an increase in delay at the central Fields-Ertel/Mason-Montgomery intersection and at the next intersection in each direction.

A high number of rear-end collisions is often associated with delays and congested conditions. Sixty percent of the reported crashes were rear-end crashes while an additional 16 percent were either sideswipe or angle crashes.

Phased Improvements Begin

In 2004, Engineer’s Offices in Warren and Hamilton Counties sponsored a limited study of existing conditions in the vicinity of the Fields-Ertel/Mason Montgomery intersection. Results of that study indicated that existing conditions at the intersections within the study area were progressively degrading with several intersections operating at less than desirable conditions.

The public and area stakeholders have participated in the study of the project area and have been supportive of the project and concurred that improvements are necessary due to the congestion and safety concerns on area roadways.

In 2012, the work of gradually addressing the traffic issues at the I-71 & Fields/Ertel/Mason-Montgomery Road Interchange began. To date, completed improvements include:

  • Northbound I-71 Exit/Gore extension & lane expansion
  • Northbound I-71 Exit/Loop Ramp
  • Southbound I-71 Exit/Additional right turn lane onto Mason-Montgomery Road
  • New lane constructed on northbound Mason-Montgomery Road from Fields-Ertel Road to Parkway Drive
  • Traffic signal improvements

You can read more about this work on our Completed Projects page.