Costs and Benefits of Widening Randall Road

The following was written by Lakewood’s Steve Willson:

Randall Road and the Job of the County Board

1. The job of the County Board

The job of the County Board is NOT to RATIFY staff recommendations. The job of the Board is to VERIFY staff recommendations. To accept the word of the bureaucracy on faith is to abdicate their role as watchdog for the taxpayers.

2. The job of the staff

The job of the staff is to provide the Board with ALL THE RELEVANT INFORMATION the Board needs to make an informed, independent decision. For complex issues, this includes EXPLAINING THE METHODOLOGY for making the decision. Has the staff done this in the case of the proposed Randall Road expansion? If not, then they are not doing their job.

3. Key factors affecting a decision to expand a road

In the case of the expansion of any road, the key factors are:

  • Is the road being used beyond its capacity?
  • Is the traffic volume increasing?
  • Is this cost reasonable?
  • What is the benefit to each driver and the cost versus benefit?

4. Road capacity

The capacity of a road is defined as the number of vehicles that can use the road per hour without traffic being slowed below the speed limit. The Highway Capacity Manual, published by the Transportation Research Board, has formulas for measuring capacity of various types of roads. According to the Highway Capacity Manual, Randall Road has the capacity to handle 1,700 vehicles per hour per lane or 6,800 vehicles per hour for four lanes.

Randall gets about 41,000 vehicle per day, or 1,700 per hour; during rush hour perhaps 6,800. It appears that Randall Road does not exceed its capacity even during rush hour.

The real problem is the intersection at Randall and Algonquin which causes congestion for all lanes during rush hour because it has single left turn lanes north and south. This issue is being addressed. Thus, the logical path would be to wait for the intersection to be finished, monitor traffic, and then to decide if there has been sufficient relief.

5. Traffic is decreasing on Randall Road

Randall Road on Tuesday, June 24, 2014, about noon.

Randall Road on Tuesday, June 24, 2014, about noon.

Traffic counts from the Illinois Department of Transportation show that vehicle traffic has declined on Randall Road over the last ten years.

Traffic is a function of population. The County has been losing population for eight years. The Illinois Department of Health projects that the population of Illinois will increase just 2.2% between 2015 and 2025. If traffic is decreasing and not likely to increase rapidly in the near future, then now is NOT the time to expand the road.

6. The County is overpaying for the work

The amount of road to be widened is about three miles. The budget that has been discussed is about $99 million. That’s $33 million per mile, or $16.5 million per lane mile. According to Highway Construction Costs, How Does Illinois Compare? (Illinois Economic Policy Institute, May 2014), “2011estimates of the generic cost per lane­mile to construct a new divided four lane interstate, for example, were… $1.88 million for urban areas.” In other words, the cost of this project is about nine times the state average for urban areas.

7. Cost versus benefit

To determine the cost versus the benefit we first have to determine who benefits. It’s NOT every driver on Randall Road; it’s ONLY RUSH HOUR DRIVERS, and they are each expected to save just one to two minutes per trip – hardly a substantial improvement.

The County Transportation Department should be able to provide accurate rush hour counts. If we estimate that HALF the traffic is rush hour traffic, that would be 20,000 vehicles per day or 7.3 million trips per year.

That’s the denominator.

The numerator is the annual cost, which we determine by amortizing the cost of the project over twenty years, its useful life. At 3.0%, that works out to $6.7 million per year.

That’s the numerator.

Divide $6.7 million per year by 7.3 million trips, and the cost per benefited trip is about $0.92, or 31¢ per mile. The average toll rate in Illinois is 6¢ per mile, so the cost is five times the average for the Illinois toll roads.

= = = = =
Below are average daily traffic counts on Randall Road from the Illinois Department of Transportation.  (

Traffic counts on Randall Road from 2005-13.

Traffic counts on Randall Road from 2005-13.


Costs and Benefits of Widening Randall Road — 2 Comments

  1. A no brainer of an equation:

    Costs: sky high;

    Benefits: microscopic

  2. You are right a 4 Lane widening of 62 going from Randall to Barrington road would be way better.

    Why even travel down Randall.

    Road is a traffic nightmare.

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