Killing Ludington Avenue: The Capacity Analysis and Map of the Proposed Road Diet

In the article I presented last week, A Road Diet of Deception, I revealed that the City of Ludington (COL) and the Michigan Department of Transportation (MDOT) had both failed in their duties to the public under the Freedom of Information Act (FOIA).  Although both entities had supplied replies that they certified as fulfilling my request for records concerning a closed secret meeting between unknown officials of the two entities in October, both were significantly different.  To whit, the COL response had numerous E-mails between the two public bodies that were absent in the MDOT reply, the MDOT reply contained a map and a 'capacity analysis' which was supposedly presented to the COL at that meeting, yet conspicuously absent in the COL's response.

As promised in that article, the capacity analysis and map was to be revealed here just after Christmas, and they follow with a little analysis.  Without access to the latest "Highway Capacity Manual", which explains how to calculate a capacity analysis, it's rather difficult to explain.  It also involves a lot of mathematical skills that my casual reader might lack.  Here is a recently made Powerpoint link to what goes into a capacity analysis, showing this complexity:

It is highly unlikely that even if the Capacity Analysis' author, Jason Ealy, was present, that he would be able to convey the complexities of the study to our city officials, and it is unlikely that he or other MDOT officials will be able to fully explain that to the public at a meeting, even should they take the time to try and explain the process.  It's very improbable that one of our other local media will report anything other than what the MDOT official says the study shows.  

The top of the Capacity Analysis for Ludington Avenue (CALA) acknowledges that Synchro 10 was used to achieve the numbers.  Synchro is traffic software used by those in the field of traffic engineering to make a variety of calculations.   Below is a tutorial that shows the powers and limitations of this software, for those wishing to understand this better.

Such software is limited by the ability of the user of it to enter the proper data and assumptions; quite often the output will lose what those assumptions were, unless they are otherwise provided in the report. As you may have noticed in the powerpoint, there are a lot of variables beyond the raw data that can shift the values, such as non-familiar users, lateral clearance, lane width, access points, heavy vehicle usage, etc.

Which is a good reason why I believe the LACA Sept 2017.pdf  is rather insufficient, because the underlying assumptions, raw data, and other relevant parameters are not addressed when the presentation is made.  Likewise, I think there are some erroneous findings within it, such as in the queue analysis which figures the longest queue (line of stopped cars at stoplights) for each major intersection (seen below):

The highlighted area indicates that when two lanes are taken away, the queue line going west will actually decrease from 124 ft. to 103 ft., which doesn't really make sense unless an assumption is made that some traffic will turn right or left at Jackson Rd to avoid the incredible line awaiting them at Washington Avenue and beyond.  Those annoyingly long queues at Washington that are going to more than double what they are now, simply because we lose two lanes with a restriping.

Despite mostly doubling and tripling queue lines going east and west the conclusion, not made by Synchro 10, but by the author, Jason Ealy, states that "the proposed conversion seems to have little detrimental impact on the corridor as a whole."  As noted, if you look at his Facebook page, you can gauge whether he is living in a fantasy world or not.

And there's nothing wrong with that, as long as it doesn't interfere with the real world we otherwise all share, and especially what we regularly drive on.  The map of the proposed changes is found here Reconfigured Lud Ave Map.pdf.  It looks as if they plan on adopting reverse angle parking in the downtown to further inhibit traffic flow.  As noted in the above link, by state law, forward angle parking is illegal on a state highway.  

Has this been thrown into the equation, or at least into the Synchro 10?  Those who would park downtown would now have to stop in the one and only lane and then back up into these spaces, greatly inconveniencing those already queued behind them.  This isn't much of a 'detrimental impact' on traffic flow and safety when added to the other problems newly created? 

If you answered no to that question, you may want to buy a Renaissance outfit, a sword (or light sabre), and join Jason Ealy's band of rebel dragon slayers.

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Even with holding this information in over the Christmas season, giving me a bad case of traffic constipation (like Ludington may have in the future), I still had a great Christmas thanks to a very special gift that carried my spirits through. More about that tomorrow.
Both beach parking fees and this diet scheme are silly, but at least the beach fee would eventually realize some money for the COL, albeit while sending a lot of tourist money away from the city as more and more beachgoers would head to the state park free beach areas or Buttersville's free access.  When they're not going to Copeyon's Splash Pad...

Excellent work X. Thanks for trying to explain what is going on.
I tried to wrap my brain around this mathematical conception of how to understand and control traffic flow and road construction but I'm going to have to rely on good old fashion common sense in order to understand what is going on here.
Government agencies are trying to take a traffic situation that seems to be working rather well and perform a radical alteration using complicated formulas, theories and explanations in order to do exactly what? Improve traffic flow? Limit traffic flow? Increase traffic flow? Increase safety? What?
This situation is not unlike the Global Warming crowds attempts to convince the World that we are facing disaster if we do not submit to their computer analysis findings and change our way of living in order to keep the Earth from boiling away.
It doesn't take a genius to understand that if the number of lanes is reduced then the flow of traffic is also reduced. The only way I can see this working is to greatly extend the time between light changes for east / west traffic flow to allow more time for vehicles to clear the business area. That of course will slow down flow of north / south traffic entering and passing through the business district.
So what is the real reason for this lane reduction? Has their been any logical explanation?

If you go through the queueing analysis, there seems to be a lot more even balance of the queues, north and south bound traffic have the longest queues in five of the fifteen intersections with the current setup.  Those longest queues will all be on Ludington Avenue (east-west) if the lanes are cut down. 

The longest queue on Harrison right now is the southbound at 61, 62 ft (which are longer than E or W queues), this nearly triples to 175 ft. and 182 ft. for eastbound traffic with the change.  This equates into a lot of congestion being forecast. 

I fail to see the safety angle of this move, the MDOT and the COL have not even tried to prove that with anything scientifically based.  With the reverse angle parking creating additional problems unforeseen previously, I only see more accidents in this corridor.

Confusing and difficult to read on purpose.

I spent 5 years working for a MDOT pre-qualified consultant.  My duties included traffic signal engineering.  While this is a little different from the capacity analysis here, I used the same tools, focusing on how changing the timing and type of signals impacted traffic flow, rather than how changing the road geometry made differences.  I noticed a number of errors in your discussion and thought it might help to have an explanation.

First, the drawings shown and linked to do not have RAP depicted.  Standard parallel parking, like what exists currently, is what is actually depicted.  The diagonals you see simply show hatching indicating no travel.  This will allow cars to safely parallel park without stopping the flow of traffic.  As such, all of the objections to RAP, while they may be valid concerns, are moot as it pertains to the analysis.

Second, it is indeed possible to reduce the queuing lengths when eliminating lanes.  The intersection at Jackson, for example, is changing from two through lanes to one through lane and one right-turn lane.  Under existing conditions, that means that the right hand lane has a mixture of cars going straight or turning right.  When a car going straight is at the front of the queue, it will not turn on red, and prevents all cars behind it from turning on red.  Under the proposal, all cars in the right lane will be able to turn right on red, thus reducing the number of cars waiting at the intersection when the light changes to green.

Finally, the queuing is only a small part of the analysis.  Of much more importance is the Level of Service (LOS) and delay.  These are generally at about the same level as the current design, with some of the side streets having significant delays under all conditions.  Think about it.  Does it really matter if you are the 2nd car stopped at the light or the 7th car, so long as you make it through in the first cycle?  A rule of thumb is that every 20 feet of queue is one car, plus or minus a couple feet.  The fact that there is a longer line really doesn't mean much as long as it doesn't extend back to the previous intersection.  As Mr. Ealy noted,

“the proposed change of US-10 to a 3 lane section generally operates well with a few exceptions.  Those exceptions are the level of service for southbound movements at Franklin/Madison and potential queueing at Washington Ave. … Otherwise, the the proposed conversion seems t have little detrimental impact on the corridor as a whole.”

From my experience as a traffic signal engineer, I would come to the same conclusion, given the data.  Of course, I can't say for certain that all the variables have been properly accounted for, but nothing stands out as exceptional.  It is unfortunate that the author of this article jumped to a number of conclusions unwarranted by a careful reading of the report and a basic understanding of street design drawings.

-Kevin Vicklund, P.E.

Thanks for your input Kevin. Are you saying that what is being proposed will not affect traffic flow or hinder the flow of traffic? Would the large influx of tourist pedestrians crossing at the intersections during the summer months have any affect on the newly designed roadway? If the road configuration that exists now is satisfactory then what would be the reason for change?

Thanks for your input Kevin. 

I have the same questions for you as Willy has above, so if you could please answer it would be appreciated.

And a few more.... I've read that the downtown lights can not be timed different as they work by sensing traffic.  Won't that hinder traffic flow?  What about UPS and FedEx drivers who usually stop in front of businesses? One lane will hinder flow extremely with them stopping for deliveries.  Have you been here or live here to experience the avenue?  I do and use the avenue downtown a lot.  I just don't see how this can't congest it more, with amount of traffic in summer and even the off season in am and pm.  Along with un-timed lights and also the short distance between the 3 lights.  ...Aaaand unfortunately with absentminded pedestrians and poor drivers.  

Thanks for your analysis, Kevin, I always appreciate feedback from those in the specialty that I may critique.  Allow me to defend the errors you noticed. 

First, the map appears to be something non-standard for what I have seen depicted in various state DOT's manuals of street design.  The hatch marks you note may have been intended by Mr. Ealy to show what you say they depict, "no travel" zones.  The drawing, however, contradicts assertions made by City Manager Shay and others through the last couple of years that "parking spaces would be wider", but otherwise remain the same number.  Currently the background map shows that 10 parallel spaces exist between Robert and Rath Street, Ealy shows 18 parking spaces will be in the new scenario (similar for other downtown blocks).  Cars will remain the same length, so the only way you could create 18 parking spaces where 10 parallel parking spaces were before is to reorient the cars to angled parking.  Ealy's 'map' is misleading to say the least and can lead to somebody presuming that RAP is covertly being planned for the future.

Second, allow me to boast that I did the traffic count at Jackson Road for a Wednesday in August, so I am perhaps a little more aware of the traffic patterns of this intersection than one who hasn't seen the raw data.  Be that as it may, we are considering only west bound traffic queueing.  If, for example, ten cars approached the Jackson light going west, let's say eight are headed west, the other two are turning north (this is close to the expected value, without loss of generality, let's agree south-turners will not affect this stat for either option).  The most regular current scenario would be two turning north will be in the right lane, along with three going straight, five will be in the left lane.  If one car equals 20 ft, the queue for westbound traffic would be 100 ft. in each lane, presuming the worst case of having a westbound car at the head of the line in the right lane.

With the right turn lane, traffic in that lane's queue will be more efficient and smaller, however, the left lane (westbound traffic) would now have eight cars (160 ft. queue).  I may be dense, but how can the westbound queue get smaller with the loss of one lane for westbound travel?

Lastly, unless you have access to the same raw data that Mr. Ealy put into his computer and could vouchsafe for the accuracy of the software, I find it sad that you use your status to give an affirmative peer review with total agreement with the conclusion.  This is why people mistrust and are reasonably skeptical of science and 'scientists' trying to advocate for doing actions that go against the grain of common sense.  Neither you nor Ealy, nor anybody in MDOT are willing to show the hard science of why this will work and be beneficial to Ludington, or even to safety.  We are supposed to take your word as professionals, sans any proofs.  

I am reminded of all those computer models that predicted global warming catastrophes, all of which never came true.  Many of those programs were written by scientists with ambiguous agendas.  If a scientist or engineer cannot explain to the public why this is a good idea just by using science and true experimental data, then it is not likely supported by science.

Willy, Brad, X, and FS, have all asked politely for Kevin to please elaborate on your first comment to this forum on the lane diet changes for Ludington. Would you kindly answer? I, along with 99% of the people I've talked to about this subject matter see absolutely no benefit or safety to this change. Thanks for your input, but, give some concrete evidence, not fictional thinking examples.

Well, I guess Kevin, our newbie, is on this forum again right now, but doesn't answer. No evidence has been given for the success of any lane change diet, so I can only assume, like X, that it's just theory from Lansing dreamers that don't function in real life like the rest of us, sad, and pathetic as usual.

How things work in Ludington

And the newbie Kevin, is on this forum 24/7 since joining too, wth is up with that? MDOT? Thanks for the new pic. too Willy, very accurate.

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