Category: Transportation

Anything related to transportation, including cars, traffic, other modes of transport, and so on.

Post #1169, Capital Bikeshare, final post for this round

Background

Capital Bikeshare is a short-term bike rental system, currently in the process of expanding in Northern Virginia.  In particular, the Town of Vienna is deciding where to place four (?) Capital Bikeshare stations.  The cost of the stations and bikes will be paid from toll revenues from I-66, so they are “free” in the sense of the capital cost being paid by somebody else.

In theory, the location of the bike racks matters greatly.  Capital Bikeshare is a “docked” bike rental system focusing on short rack-to-rack trips.  Bikes must be picked up and returned to one of Capital Bikeshare’s “docks” (slots in their locking electronic bike racks).  Users may rent a bike via annual membership, one- or multi-day pass, or credit card at time of rental.  Stiff financial penalties apply for failure to return a bike to a rack in a timely fashion.  For the casual user, the first half-hour costs $2, the next costs $2, the third costs $4, and the fourth and higher half-hour increments cost $8 each.  If you (e.g.) use your credit card and accidentally keep a bike outside of a rack/dock for an entire eight-hour day, that will cost you $112.

In other words, this is a bike rental system strongly oriented toward going from A to B, where A and B are Capital Bikeshare racks less than a half-hour bike ride apart.  That makes the location of A and B crucial to the use of the bikes.  To be clear, Capital Bikeshare is NOT a bike rental system for people who just want to ride around for a while and aren’t quite sure of their destination.  Based on their member surveys, their members overwhelmingly use Capital Bikeshare because it’s the quickest way for them to get from A to B, typically a very short work commute.

In practice, however, Capital Bikeshare typically gets so little use out here in the suburbs that it may not much matter where Vienna places its Bikeshare racks.  That was the main finding of my analysis two years ago.  If you have an interest in Capital Bikeshare in Fairfax County or Vienna, VA, you should start by reading my original analysis, in this unnumbered post from 2019.  Two years later, that still stands up as a pretty good piece of analysis.  Among the highlights are the following, all of which are documented in that post:

Each bike rack costs around $45,000

Each bike costs about $1000 (2011 data) or maybe $1200 (2015 data).

In addition to those capital costs, the annual operating cost per bike is somewhere around $2000 (2011 data, Wikipedia) to $2800 (2019, calculated from Arlington, VA fiscal report).

Best guess, on any given weekday, in the peak month, the entire Tyson’s Bikeshare network serves about six people/12 trips (2018 data).  That’s with a fleet of almost 100 bikes deployed across 15 racks.

In Tysons, three-quarters of the Bikeshare racks are used for less than one trip per day, on average.  In Reston, 69% of the racks are used for less than one trip per day (2018 data).

The “use rate” (bike trips per bike-parking slot) of Tyson’s Bikeshare racks is just 6% of the all-metro-area average Bikeshare use rate.

That low use rate was not expected. The 2018 Reston use rate is less than 20% of the level projected for the second year of operation in the Reston bikeshare feasibility study (.pdf).  With this most recent analysis, we know the use rate is not increasing.

The low use rate in Tysons generates an absurdly high cost per trip. My estimate from my prior analysis worked out to an average cost of $25 per bike trip.  That compares to a calculated all-metro-area average cost of just over $3/trip.  Data for Arlington County (.pdf) works out to around $7/trip

Capital Bikeshare is owned by our local governments, but it’s operated by a private for-profit enterprise.  It’s not clear that any entity involved with this has any incentives other than to expand the network regardless of value.

Despite having hundreds of racks placed in this area, there is no standardized process to guide the choice of rack locations.  Every locality gets to decide it on-the-fly.

Current data analysis:  Merrifield.

In my last post, I did enough analysis of more recent Capital Bikeshare trip data to show that nothing had changed materially since my earlier work summarized above.  For the Reston area, the number of trips was stable through 2019, then declined in the pandemic.  For the Tysons area, they increased the number of bike racks by 50%, and and the number of trips increased by about 50% in 2019.  In both cases, the value proposition remains the same or worse than it was.

Let me quickly reiterate the (lack of) value proposition at the low Tysons use rate.  Arlington County’s 2019 financial report (cited above) shows an annual operating cost of $2800 per bicycle.  That’s not hugely different from the roughly-$2000-per-bike 2011 figure cited by Wikipedia.  It’s hard to say what it would be for Fairfax County, but I believe the for-profit company that manages the system gets a fixed per-bike fee.  Let’s assume Fairfax’s average cost could be at the lower $2000 figure.  Tyson’s Bikeshare racks were reported to have almost 100 bikes available on July 4 (see just-prior post).  For all of 2019, there were about 5700 trips that used those racks.  When I do the math, that comes out to an average operating cost of $35 per half-mile bicycle trip.  And that’s assuming that all the capital equipment (racks, bikes, kiosks) is free.

The upshot is that by any plausible estimate, the Tyson’s area cost per trip is ghastly.  For example, you can buy a Schwinn comfort bike for $300.  For the estimated annual operating cost of the Tysons portion of Capital Bikeshare, you could give away about 650 of those bikes, per year.  I’d bet that’s far more than the number of people who used those Tysons bike racks in 2019.  You could literally give every user a new bike, every year, for what it costs to supply those rental bikes.

The only thing that’s really new in this whole picture is Bikeshare at Merrifield.   The three racks in that area seem to have an above-average use rate, at least during the peak months of use.  During the peak month, each bike dock sees about one bike trip every four days (0.27 trips per day).  And while that’s a pitifully low rate compared to the racks in the DC urban core, it’s the best of the four Fairfax County areas.

So, the question is, why?  Why does Merrifield appear to outperform the other three regions of Fairfax County?

My answer is that it combines enough apartments and shopping, near metro, that you get a few people to use those bikes every day.   Although there is no personal identifying information on the trip data, you can use some clues to infer what a typical trip was for.  A short trip, during rush hour, involving the Metro station, by somebody who has an annual membership, is probably a Metro commuter.  By contrast, a long round-trip around a Bikeshare station, mostly by non-members, mostly not during rush hour, is probably somebody out running an errand of some type.

That logic is what I’m trying to show in the table below.  This takes all the trips involving Merrifield stations during the peak months of June to September 2019, and tabulates them by start and end points.

Probably, an average of three commuters used those bikes steadily to get to and from Metro.  That yielded an average of six trips a day.

But on top of that, there’s another 3.4 trips per day that look like shopping/dining trips to me.  These were either long round-trip excursions from a single location, or people going to and from the Mosaic shopping district.  These were typically not during M-F rush hour, and typically involved a lot of casual (non-annual-membership) users.

The upshot is that the entire Merrifield Capital Bikeshare system served a handful of people a day during the peak summer months of 2020.  Six, maybe?  That was three or so commuters to and from Metro from nearby apartments.  And maybe another three or so shoppers/diners, mostly taking round trips from the Metro or the other two destinations.

And that was enough to make the Merrifield area — with 37 functional bike docks, in three racks — by far the busiest in Fairfax County.

Just to beat that dead horse one more time, if Fairfax really does see a $2000+ per year operating cost per bike, as Arlington does, then for the first full year of operation, Merrifield Capital Bikeshare rides had an average operating cost of $9 per trip.

It’s still cheaper to use Uber.

To my eye, the Town of Vienna has none of the advantages that Merrifield does in this situation.  It doesn’t have a lot of purpose-built Millenial-friendly apartments under a mile from Metro.  In fact, there’s nowhere to build apartments within a mile of Metro.  It doesn’t have a hip Millenial-oriented shopping district with a mile of Metro either.  And ditto on the ability to build one.  All of the synergy that yields that outstanding nine or ten bike trips a day in Merrifield will be missing here.

I would therefore expect to see less use of those racks in Vienna — no matter where they are put — than is currently the case in Merrifield.

So, where should Vienna put those Bikeshare racks?  It just doesn’t matter.  But it would be good to be clear about who is paying for the operating costs of keeping them running.  It’s one thing to waste some other taxpayers’ money.  It’s a different thing entirely to waste our own.

 

Post #1168: Capital Bikeshare again, part 2

 

More than two years ago, I looked at Capital Bikeshare use in suburban Fairfax County and concluded that Bikeshare was largely a waste of the taxpayers’ money.   The use of those docked rental bikes was far below what is seen in (e.g.) central D.C., and as a result, the average cost per trip was exceptionally high.  My estimate was that Tysons area Capital Bikeshare trips had an average cost of about $25 each, and an average length of less than a mile.

In this post, I refresh that analysis and see whether or not use of those bikes has changed markedly in the subsequent two years.

To cut to the chase, it appears that the only truly successful Bikeshare stations in this area are the three stations serving Merrifield.  (Successful in the sense of getting a lot of use).  As the Town of Vienna contemplates where to put their its own racks, there may be some lesson there. Or maybe the Vienna racks these will end up just as nearly-useless as they appear to be in Tyson’s, just up the road.

You should look at the just-prior post to see all the links to my original analysis of this issue.

Continue reading Post #1168: Capital Bikeshare again, part 2

Post #1167: Capital Bikeshare, again, part 1.

I see from a recent article in the Tyson’s Reporter that we’re still in the process of bringing Capital Bikeshare to Vienna.

Aside 1:  Capital Bikeshare is a “docked” bike rental system, where bikes must be returned to some Capital Bikeshare rack. The system is set up for short rides, as additional charges typically accrue after the first half-hour. Essentially, you plan your ride to go from one rack to another. The bike itself is a three-speed fat-tired bike weighing nearly 50 pounds. It has been quite successful in the DC urban core, and not very successful at all in the lower-density suburbs.

Aside 2:  I am not a bike hater.  To the contrary, I am lifelong avid bicyclist and have supported the Washington Area Bicyclists’ Association by taking out a lifetime membership.  Locally, I bought (and still ride!) the first bike ever sold by Bikes of Vienna (then Bikes@Vienna), a Bike E semi-recumbent, pictured above.  Back in the days when the internet was new.

To me, knowing what I know, that article seemed ridiculously upbeat about the current and future prospects for Capital Bikeshare in this area.   I say that because, as of two years ago, installing those Capital Bikeshare racks in this area looked like a complete and total waste of money.

And, as is typical for this website, that statement was based on detailed analysis of data.  In this case, public-use data provided by Capital BikeShare.  As of two years ago, the Capital Bikeshare racks at the Tysons and Reston Metro stations were virtually unused.  They might have six riders using them on any given day.  With the high fixed (capital and maintenance) costs, that generated an average cost of $25 per bike trip for the Capital BikeShare bikes at the Tysons Metro.  It would have been vastly cheaper literally to pay for daily Ubers for half-dozen individuals who used the Tysons Capital Bikeshare racks on a typical day.

The upshot is that Capital Bikeshare works well in the dense urban core of Washington DC.  It works to some degree in the densely-built inner suburban areas.  It doesn’t work at all way out in the distant, low-density suburbs.  Not in Virginia, not in Maryland.  Both states saw the same patter of extremely low use (and so extremely high average cost per trip).

This post is just a listing and summary of my prior work.  It’s all pre-pandemic, and uses data slightly more than two years old.  At the time, there was no significant upward trend in use, but clearly I’ll have to revisit it to check that.  A subsequent post will refresh those analyses with more current data, assuming Capital Bikeshare still provides those public-use datasets.

Maybe the world has changed, and it’s all sunshine and roses in the market for 50-pound fat-tired rental bikes, out here in the low-density, no-bike-lane suburbs.  But I suspect that little has changed, and this is just another case of a government entity that has more money than it knows what to do with.  In this case, with a budget force-fed by I-66 tolls.

Prior work

  1.  Maps showing the flow of trips at Tysons and Reston metro (in this unnumbered post).  Those maps are still there.  On a computer, click the gear icon in the lower left corner and turn on animation to see the full visualization of the trips.  The text of the post characterizes the number and direction of trips.  There’s a map for the entire Capital Bikeshare system toward the end of the post.
  2. Detailed analysis of cost and ridership for the Tysons’ Capital Bikeshare racks (in this unnumbered post).  That’s the analysis where I derived the estimate of $25 per trip, average cost, for the Tyson’s racks.  This post also goes through the obscure and muddled economic incentives of this public-private partnership.  (The racks are owned by local government, but the company that runs and services the system is a private entity.)
  3. The huge government per-trip subsidy probably explains why Capital Bikeshare is coming, but private providers of dockless rental bikes and scooters won’t touch Vienna.  You can see the dockless bike alternative laid out in this unnumbered post.
  4. Finally, FWIW, this unnumbered post has a summary of a February 2019 Transportation Safety Commission meeting in which Capital Bikeshare was first discussed.  My take on it is that they were ask skeptical of the success of Capital Bikeshare here as I am.  But we’re still getting Capital Bikeshare, because it’s “free”.

Post #1020: PriUPS

This post is prompted by a recent article on Texans using their hybrid vehicles as electrical generators.  This being Texas, of course the vehicle in question is a pickup truck, in particular, the Ford F150 hybrid pickup.

And so, in 2021, Texan F150 hybrid owners are finding out what Prius owners have known since at least 2005:  A hybrid car makes an excellent backup generator.  In this post, I’ll lay out the simplest approach to using your Prius (or similar full hybrid) as an emergency generator. Continue reading Post #1020: PriUPS

#531: The $9M Patrick Henry parking garage?

When did this become a $9M project?  Beats me.  Last I recall, the only number mentioned was something like $4.7M.  Pretty sure that lower number was what was in the discussion of the capital budget.

I guess I haven’t been paying attention, because that’s the first I’ve seen of that $9M number.  But there it is, in black and white, in the documentation for that portion of tonight’s Town Council meeting, which you may access on this Town of Vienna web page.

Wait, doesn’t $9M for 188 spaces work out to be near $50K per parking place?  Didn’t (at least some) Town Council members balk at paying far less than that, for a parking garage on Mill Street?  Again, I must not have been paying close attention, because that’s sure how I recall it.  Isn’t that vastly more per space than the Town is going to pay at a proposed Church Street garage?  What the heck?

How many parking places does the Town need at this location?  You’d figure, you’d get a clear idea of that first, then proceed, right?  Nope.  Not clear that anybody has any estimate of that, but … but the Town will eventually do some sort of study, at some point, to guess at that.  It’s on the calendar for some time a couple of years from now.

How much time does the Town have to think this over?  One month.  According to Town staff, the agreement has to be signed no later than next month’s Town Council meeting.

Does this have anything to do with a modified Capital Improvement Plan (CIP), for the Town Council to re-approve at this meeting?  See materials on this Town of Vienna website page. Maybe, I haven’t quite had the time to look at it, except to see that, when the Town couldn’t fit the $35M borrowing into its current economic model, it … changed the economic model so that the $35M in proposed 2020 borrowing now fits.

Is the 2020 bond issue still, by far, the largest amount the Town has ever borrowed?  Yep.

Do we still burn through all the reserves in the bond fund, down to the agreed-upon $2M minimum safe level?  Yep, somehow, with the new economic assumptions, the reserves fall to exactly $2M with $35M in borrowings, which is exactly the minimum acceptable level.  (This is from materials for Tonight’s Town Council meeting).

Does that new projection include additional 2022 and later borrowings to cover the increased cost of the parking garage?  Not clear, because not shown.  Last time around, the figured the cost of the garage in as about $4.7M, but free to the Town (paid for by some other entity).  So it’s not clear that an additional $9M in liabilities has been worked into the future borrowing scenario.  Here’s how the Town’s projected borrowings stood as of the last (what I though was the final approved) version of the CIP.  (This is calculated from the prior CIP, not the new CIP to be approved at tonight’s Town Council meeting.)

Today, gold hit $1673 per troy ounce (per Kitco).  Does anybody remember or care what happened to meals tax revenues for 2009, during the last recession?  Nope.  Likely I’m the only person in Town who cares about that.  But just FYI, here’s the historical on that one:

Does it bother anyone but me that the Town is projecting no trouble paying for all this, based on nothing but ultra-strong revenue growth for immediate, mid-term, and far future?  Apparently not.

How long does the Town Council get to think about this new proposed CIP?  Per the presentation, no time at all — they have to approve it tonight.

Post #518: The 1/28/2020 meeting of the Transportation Safety Commission

You can download my recording (.mp3) of the roughly 30 minute meeting at this Google Drive link.  The meeting was short, I took no notes, and the following items are a handful that I noted when listening to the tape.  Approximate times into the recording are given in mm:ss.

Scooters! (01:15).  The Town has posted its rules for rental scooter contractors who wish to offer scooters in the Vienna.  So far there have been no takers.  The Town Council modified the original TSC recommendation to a) reduce speeds to 6 MPH along Maple and Nutley (with the understanding that scooters would likely be on the sidewalks there), and b) asked that similar reduced-speed zones be set up around schools, parks, and (I think) the library (?).

Chick-fil-A drive-through exit pedestrian safety issue (03:08).  This issue is my reason for attending.  You can read the background in Post #423 and thereabouts.

Briefly, the transformers in front of Chick-fil-A prevent prevent persons exiting the drive-through from seeing pedestrians or bicyclists approaching from their right.  I raised this as a safety concern at the last TSC meeting.  The upshot is that a) Town staff and at least one TSC member agree that this is a hazard and b) Town staff are working with Chick-fil-A to get a mirror in place so that drivers can see pedestrians and bicyclists approaching from the blind side.  This is about as good an outcome as I could have hoped for.

Improvements to W&OD bike crossings (05:25).  They summarized the Town Council proposal for changing the W&OD bike crossings on Park and Church to make them, in effect, a raised crosswalk — like a speed table.

Bicycle Month (06:40).  This is a series of bike-related events sponsored by or with participation of the Town of Vienna government, slated for May 2020 this time around.   It sounded like the Bicycle Advisory Committee may be looking for sponsors for some of those events, and if so, presumably the chair (Beth Eachus) would be the person to contact.  They also discussed need for signs on the W&OD to direct bicyclists to businesses near there.

Revised Citizen’s Guide to Traffic Calming Measures (09:25).  This was a description of what is being planned to finish off the revised version of (what used to be called) the Citizen’s Guide, that is, the handbook that laid out how neighborhoods could apply to have traffic calming measures (e.g., speed bumps, signs) installed on their roads.  Later in the meeting, a citizen raised some questions about comments on the Citizens’ Guide to traffic calming (29:25).  At that point, they did a recap of the likely schedule moving forward.

Apps that direct cut-through traffic onto neighborhood streets (10:20).  This was a rather cryptic item, but apparently Fairfax County has noted that widely-available traffic apps are directing more traffic through neighborhood streets, to avoid slow arterial roads.  I’m not sure what the upshot of this is.

Plans for a Town of Vienna self-directed walking tour or historical sites walking tour (11:00).  This was just presented as a concept, no details.

Extensive discussion of the Robinson estate sidewalk bequest (12:10).  This is a sum of several million dollars, for use in sidewalk construction in the Town of Vienna, but it comes with numerous restrictions.  It’s to be used for concrete sidewalks only (not, e.g., for any associated storm water management), it’s to be used within a reasonably short time frame, it’s to be used to fill gaps in the existing sidewalk network, and so on.

Specific issues with Tapawingo (potholes), Marshall Road (pedestrian light), (15:40)

Followup on Tapawingo and Kingsley meetings with citizens regarding traffic calming (19:50).

School-zone 25-MPH flashing signs in 25-MPH zones (20:40).

Dealing with excess signage on some streets (23:50).

Timeframe for study of the neighborhood bounded by Maple/Courthouse/Nutley (28:15).  Upshot is that the study will be several months away, as they wanted to get traffic counts only after winter has passed.

Post #511: Three followups to the last Town Council work session

Source of this image is linked here.

This is about three unrelated points from the Monday Town Council work session that, in hindsight, struck me as possibly worth writing up:  The Town traffic simulation, the treatment of the Town strategic “plan”, and the end game 18 to 24 months from now.

Town traffic simulation.

Part of the Town’s “Multimodal” traffic study estimated the impact on traffic congestion from Maple Avenue development.  I’ve spent a lot of time trying to figure out what the consultants did to arrive at their numbers.  As of last night’s meeting, I have officially given up on that, because I can’t make head or tail out of it.

But I did take away one thing from trying to puzzle that out:  There’s a lot of uncertainty (wiggle room) in that calculation.  That’s worth noting, I think.  See if you can follow this.

  1. Back in August, the contractor presented results showing 758 additional net new evening rush-hour trips from Maple Avenue redevelopment.  They did not talk about it during that presentation, or during their next presentation.  But it was on a slide that they skipped over (Post #358).
  2. One issue I had with that is their “baseline” traffic, i.e., the number of trips that they assumed occurs right now.  Their graphic clearly showed that they assumed that (e.g.) currently-empty buildings were generating traffic on Maple.
  3. The single worst example of that was the assumption that the Suntrust Bank (east) currently gets 381 trips in the afternoon rush hour.  As previously noted, that’s a ludicrous number — it amounts to one car going into or out of that bank parking lot every 10 seconds.  Councilman Majdi called them out on that, but both the contractor and Town Manager strongly defended that as “science”.  I was so ticked by that misuse of the term “science” that I sat in the bank parking lot and counted cars to demonstrate that the actual traffic to that building was about one-tenth of that (Post #465).
  4. When I want to look at the final report, I couldn’t find those 381 trips.  As it turns out, at yesterday’s work session, it was revealed that the contractor removed those 381 existing trips from the baseline.  Simply zeroed them out.  That’s why they are no longer in the report. And so, presumably, we have no further cause for complaint.
  5. OK, fine, I can do arithmetic.  If they remove 381 from the baseline, that should then add 381 to the net new trips.  (Why?  Because you net out the existing traffic, when calculating the net new traffic.  If you reduce existing traffic by 381, then you should have increased the net new traffic from development by 381.
  6. And yet … in the final report, the net new trips from Maple Avenue actually decreased from 758 to 500.

So, without pondering how they justified that, just do the math.  Focus on the simple arithmetic of how they had to have gotten from the prior estimate to the current estimate.  Solve for X:  758 + 381 + X = 500.  Turns out, X = -639.  That is, they managed to extract a further 639 net new trips out of their analysis, to get from the original estimate that (presumably) netted out the Suntrust 381 in the baseline, to the final estimate that did not.  Just as a matter of arithmetic.

This X factor of -639 trips is what economists call a structural uncertainty in the estimate (as opposed to a statistical uncertainty).  It’s the uncertainty that arises from doing the numbers one plausible way versus another (as opposed to a more traditional statistical uncertainty, which arises from purely random factors, so to speak).

So this lower bound for the true stuctural uncertainty of the estimate — how much it changes based on choices made by the analyst — is larger than the estimate itself.

A lot of other things about the methods and results looked counterintuitive to me.  For example, the net new traffic during the AM rush hour, to the extent that it left Vienna, flowed mostly westward (i.e., against the direction of morning rush hour traffic).  About 2.5x as many additional cars exited Vienna at Nutley as at Follin.  But put those issues aside.  The simple arithmetic of getting from the draft to the final — the X above — is what convinced me that I would never have any real understanding of how they arrived at their numbers.

So this is truly a black box, and a black box it shall remain.  There are open-source software packages that allows individuals to model transportation networks (e.g., here, here, or here.)  All of them require considerable amounts of data as input (e.g., traffic light timings, traffic counts).  I’m not going to put in the effort to try to gin up my own estimate.  But my conclusion is that this is the only way to avoid having the results be a total black box.

Addendum:  Traffic counts and the K-Q curve.

Addendum:  I also have no clue what these traffic models do when actual traffic passes the peak of the “K-Q curve”.  (Briefly, as you try to stuff more and more vehicles through a given roadway (increase the density of cars per square foot, traditionally represented by “K”), each individual car may move more slowly, but in aggregate, the total flow of cars (represented by the letter “Q”) increases.  That is, at first, each car may move slower, but you get more total cars moving through the road segment.  But as you continue to add cars, you reach a point where the reverse is true:  You get so crowded that adding more cars actually reduces total traffic flow.  Not only does each car move more slowly, but you actually get fewer total cars to pass through the road segment in a given amount of time.  That point — where jamming more cars onto the road actually begins to reduce not just speed, but total traffic flow — that’s the peak of the K-Q curve, as in this diagram (k = density of cars, q = total flow of cars through the roadway, v = average car speed).

Source:  Wikipedia.

As I understand it, this is the reason you will see (e.g.) metered on-ramps (ramps with traffic lights) at the on-ramps to the inside-the-beltway portion of I-66.  They are trying to avoid passing the peak of the K-Q curve.   Once you pass that peak, you are helping nobody by allowing more cars onto the roadway.  Not only does every individual car move slower, but you actually get fewer total cars to pass down the highway in a given amount of time.  All you do is increase the size of the backup.

It sure seems to me that we hit the peak of the K-Q curve during morning rush hour.  At least sometimes.  At the point where traffic from the Courthouse and Maple light backs up all the way to Nutley, it’s tough for me to imagine what we haven’t hit and passed the maximum possible through-put of the Maple-Courthouse intersection.  Here we are, just before 9 AM, looking east and west on Maple, at the Nutley Street intersection.

But here’s the technical question.  Look at the diagram above and think of the curved line as a hill.  In terms of traffic counts, you get the same traffic count if you are halfway up the upslope of the hill (before the peak of the K-Q curve, where traffic is light and moving well) as you do halfway down the downslope side of the hill (past the peak, where traffic is packed and moving slowly).

I think this explains one oddity of the report, in that the consultants seem to think that we have one long rush hour period from about 8 AM to about noon.  Because they are looking at the traffic counts, and the flow of cars is about the same throughout that period.  Like so:  The flow of traffic (cars/hour) is the same at 9 AM as it is at 11 AM.

Source:  Vienna multimodal transit report, 12/20/2019 draft, page 3-13.

But as anyone who drives that road can tell you, there’s a stark difference in the level of traffic queues or waiting times between 9 AM and 11 AM.  Just before 9, traffic routinely looks like the pictures above.  Whereas around 11 AM, traffic flows far more freely.  But you see no difference on the graph above, because the traffic counts, by themselves, are blind to the fact that Maple hits capacity during the rush hour.  The count you get when you are on the downslope side of the K-Q curve (just before 9 AM, with huge backups as pictured above) is the same as the count you get when you’re still on the upslope of the curve (around 11 AM say, when traffic moves pretty well).

So that’s just an oddity that I noticed.  Traffic counts (cars/hour) do not, by themselves, accurately measure traffic, because of the ambiguity caused by hitting the peak of the K-Q curve.  Very light traffic and very heavy traffic can generate identical traffic counts.  And the graph just above doesn’t show that we have one long rush hour.  It just shows that the total traffic counts don’t change much between the absolute peak of the AM crunch (which I place at about 8:45 AM) and the must less crowded mid-morning period.  I think that, as much as anything, demonstrates that we hit some measure of capacity on Maple during AM rush hour.  Once you hit capacity on Maple — as I infer that we due during the AM rush — additional traffic does not result in additional traffic counts.

I’ll mention one other truly weird possibility.  At this most recent meeting, Coucilman Noble made much out of the new traffic light system that Vienna is getting.  (I have the vague notion that VDOT, not the TOV, is responsible for that, but that doesn’t matter).  If that traffic light system actually increases throughput during the periods when Maple is at capacity (something that I doubt will happen, per discussion of capacity above, but is possible), then, by traffic counts alone, it will make it look as if traffic has gotten worse during rush hour.  That’s just another example of the way in which traffic counts, alone, can provide a misleading indicator of traffic when a road is at capacity.  If there’s a fundamental change in the roadway (in this case, new light timing), traffic (counts) going up can mean that traffic (wait times) is going down.

And as a final, final note on that, if the Town of Vienna wants Vienna citizens to be aware of some profound benefit they are going to get from new traffic signals, I suggest that they actually provide at least some sort of description of what they intend to do.  Near as I can tell, the entirety of what Vienna has to say about this project is a total of 23 words on this page on the Town of Vienna website.  Normally, as you may realize, I will do my homework to understand what the Town is about.  But from the description, I can’t even find the words to Google up what this is.

 

Town Strategic “Plan”

In theory (and by law), anything the Town of Vienna government does needs to comply with the Town’s strategic plan.  But if you look back at when the Town developed MAC zoning, they developed MAC zoning (2014), then rewrote the strategic plan (“mixed use development) to match it (2015-2016).

This more-than-begs the question of what you mean by “plan”, if you rewrite the plan to match what you subsequently decided to do.  I have a vague idea that it isn’t even remotely legal to do that.

That said, based on the last work session, that’s the plan going forward.  When Councilman Majdi brought up the idea of addressing the comprehensive plan first, that was (of course) immediately shot down.  The agreed-upon sequence is now to rewrite the zoning (with apparently no restrictions whatsoever), and then once again rewrite the comprehensive plan to match whatever comes out of the zoning rewrite, if necessary.

Just in passing, and to underscore how loosey-goosey this is, Town staff have now set it up so that this Town Council is actually providing less guidance to this process than occurred during the original development of MAC zoning.  At least, under MAC, Town Council somehow arrived at a firm limit on building height.  Here … near as I can tell, anything goes.  Town Council has not publicly agreed on even one single thing that they want to see in a revised MAC zoning.  It’s all up to the Department of Planning and Zoning.  That’s no surprise, given that Planning and Zoning appears to be controlling this process.

Looking 18 months down the road.

Fundamentally, the limit on the density of development on Maple Avenue appears to be a political limit.  It’s really about what the median Vienna voter wants.  There’s no technical barrier to filling Maple Avenue with Chick-fil-A-car-washes.  It’s just that the people who live here do not, on average, seem very fond of that idea, and they will vote for people who say they won’t do that.

This is all the more true if you purposefully ignore any other possible limits to growth.  E.g., if you will not discuss development in the context of the capacity of Maple to move traffic, or in the context of impacts on nearby residential neighborhoods.  Barring all that — if you acknowledge no other limits — then the only limit on the density of Maple Avenue development is a political limit.

This is a point that Councilman Majdi brought up at that work session.  And either his fellow Council members didn’t get it, or they just shot it down as sort of knee-jerk reaction.

So I need to point out the following:  Town staff have structured this process so that our elected officials have no say in shaping the new MAC.  They will have no formal input in what happens to MAC zoning until the very end of the process.  The process will be controlled by the Department of Planning and Zoning, with input from the Planning Commission (still largely staffed by holdovers from prior Town Council.)  Only at the very end of the process will Town Council be presented with the finished products.

Councilmember Patel tried to reverse that — to get Town Council to have first say over the shape of the revised MAC zoning — and got quashed by the pro-MAC members of Town Council.

So I’m just pointing out the disconnect here.  The only functional limit on MAC density is a political limit.  And our political body is (formally, at least) completely shut out of the process of shaping the new MAC, until the very end.

The only logical conclusion is that this is likely to end (or, at least, risks ending) in some sort of train wreck.  The people actually structuring the new MAC are not subject to any political constraint — they are not elected.  And the people who are elected are not part of the MAC-rewrite process.  That’s exactly what the response to Councilmember Patel established.  But in the end, the constraint on what can and can’t be done is a political one.   So this is a fundamental mis-alignment of incentives, and poor overlap between scope of authority and scope of responsibility.  Town Council is going to be responsible for what comes out of this process, but they have been stripped of all authority to shape it.  

What guarantees that Town Council will be handed a new MAC that is politically acceptable?  Nothing.  The process is literally and purposefully structured that way.  Any notion that Town Council would offer overall guidance (by having first crack at proposals) was firmly snuffed out at this past Town Council work session.

And that’s the scenario that I reckon as a train wreck.  Suppose the very-pro-development Department of Planning and Zoning, working in a political vacuum, comes up with a zoning proposal that appears unacceptable to the median Vienna voter.  Then what happens?

I believe that Town staff are actually counting on that possibility of train wreck.  That is, they are counting on being able to cram this down Town Council’s throats, at the end of the process, one way or the other.  They think that those who oppose larger buildings and higher-density development will blink, in order to avoid that train wreck.  (E.g., to avoid vetoing a proposal that too two years and a quarter-million-dollar contract to develop, and that includes a bunch of purely technical and non-controverial fixes to Town Code in addition to a rewritten MAC.)  By refusing to separate out the non-controversial “clean up” portion of this work, from the more controversial changes to Town zoning, they can given Town Council a one-vote take-it-or-leave it choice (as I have already noted, per Post #483 and others).

Or, possibly, they are hoping that this next election will lead to a change in the fortunes of the pro-MAC portion of Town Council.  So that by the time this comes to a vote, they’ll have the votes for a higher-density MAC zoning.  That’s certainly possible.  From what I can tell, the anti-MAC forces seem totally disorganized at this point.  I guess we’ll have to wait and see.