Stop Longmeadow



Longmeadow Will Not Reduce Traffic Congestion

KDOT is trying to convince the Kane County taxpayers that Longmeadow Parkway will significantly reduce traffic congestion on the existing Fox River Bridges.  This contention is totally false, and the County’s own analysis proves it.  It is an analysis the project’s proponents do not want to address.  

But first, let us review a bit of history -

In the mid-1980’s IDOT recognized that growth west of the Fox River would create traffic issues.  As is their job, IDOT began a process of planning a north-south spur on I-90. It was called the Fox Valley Freeway.  The political forces of the day limited IDOT’s planning to a corridor that ran mostly up the east side of the river.  In order to feed traffic to the new expressway new bridges across the Fox would be necessary.   

A long and tortuous process began to identify bridge locations.  After much work IDOT realized that an expressway on the east side of the river was a bad idea, because the growth was on the west side of the river.  As a result, in 1993 Gov. Edgar killed the expressway.  Although the Fox Valley Expressway died, the bridges lived on.  However, since they would no longer serve a specific need, they were re-purposed to provide (In KDOT’s words), “diffuse benefits” and to “make the road system more efficient”.

Many locations were studied and several, including Longmeadow (then known as the Bolz Rd. Bridge) were picked for implementation.  Bolz Rd. was picked not because it was effective in reducing congestion, but because it was expected to cause the least objection from the electorate and the political establishment.   In fact, at the time the McHenry Co. Engineer, Mr. Michael Magnuson summed it up well when he said,

“…….. a new bridge either north or south of Illinois 62 would handle predicted new residential growth to the west, but wouldn't improve current traffic problems”.  

This was true in 1995, when he said it, and it is still true today.

In 2006 KDOT hired a well-respected consulting firm, Wilbur Smith & Associates, Inc. to study the feasibility of Longmeadow Parkway.  They began by studying present and future traffic flows across the Fox River bridges in Algonquin, Carpentersville, Dundee and I-90.  They began with data from the CMAP (Chicago Metropolitan Agency for Planning) model which provides a good regional picture of growth and traffic.  

However, realizing that the CMAP model is really not suitable for project-level studies, Wilbur Smith developed a computer simulation model that is specific to the local situation.  In 2007 they tested their model for accuracy by comparing it to actual “on the ground” data.  They went out on the roads and counted cars.  This comparison showed that their model was reasonably accurate, with a margin of error of 10%.

Wilbur Smith then proceeded to analyze traffic flows that were expected to occur about five years into the future.  The results of this analysis are summarized in their report titled “Traffic Projections and Financial Feasibility Study”.  They investigated the effects on traffic volumes of various levels of tolls on the bridge.  They also looked at traffic volumes on the existing Fox River bridges that would occur if the Longmeadow bridge were built, and if it were not built. 

The results of their study are summarized in a Table on pg. 60 of their report and in a bar graph on pg. 62.  The bar graph is reproduced below.  It shows the traffic volumes for the recommended tolling scheme.

The No-Build shows conditions without Longmeadow; the Full Build shows conditions if the entire Longmeadow project is built terminating at Rt. 62 in Barrington Hills; and the Partial Build refers to a shortened version of Longmeadow that terminates at Rt. 25 in Carpentersville.  

Traffic volumes are indicated by the height of the bars.  Medium blue is the bridge in Algonquin, yellow is the Carpentersville bridge, light blue is Rt. 72 in Dundee and purple is I-90.  Traffic volume on the Longmeadow bridge is shown in red.

As the graph clearly indicates, there is virtually no difference in traffic across the existing bridges whether or not Longmeadow is built.  The height of the bars is hardly changed.  If one looks at the table of data in the report, it shows a small difference for the Algonquin bridge amounting to a 5% reduction.  But remember, the model’s margin of error is 10%.  The reductions on the other existing bridges were even smaller.

Interestingly, building Longmeadow does have an effect on the I-90 traffic volume (the purple bars): it reduces I-90 traffic.  

The Wilbur Smith report is telling us:
1 – Longmeadow does nothing to reduce traffic congestion on existing bridges
2- Longmeadow is expected to divert traffic off the Tollway and onto local roads

Proponents of the Longmeadow project are clearly wrong when they say the new bridge will solve current traffic problems.  They may say that we need it for “future” problems when traffic volumes are greater.  They have no evidence to back up this claim.  

Even if they could show that traffic volumes will increase, they cannot show that the Longmeadow bridge will have any effect on reducing congestion.  It is simply the wrong bridge in the wrong location. (Mr. Magnuson apparently knew this in 1995)

When all items are considered, Longmeadow Parkway will cost in excess of $200 million.  This comes at a time when all governments and taxpayers are severely stretched, and when all are struggling to build essential infrastructure and maintain existing roads and bridges.  Now is not the time to spend $200 million on a project that has little, if any demonstrable benefit.