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Other San
Antonio Area Roads
Bandera
Road proposals |
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| This page last updated November 26, 2019 |
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The
proposals on this page are conceptual
The options
discussed below are in the very early stages of development and there
are no plans at this time to implement anything shown here. Because of
widespread interest, this page is provided to explain these proposals
and the current planning status. Everything
on this page is subject to change. |
Bandera
Road (SH 16) between
Loops 410 and 1604 in Leon Valley and Northwest San Antonio is the
eighth most congested road in the region and 62nd most congested in the
state. About 70,000 vehicles a day use
the southern third of the route, about 55,000 the center
third, and about 35,000 use the northern third.
To put that into perspective, the section of Loop 410 on the
South
Side between
I-35 and I-37 carries about 50,000 vehicles per day , and the stretch
of Loop 1604 between SH 151 and US 90 carries less than 40,000
vehicles per day. So improvements
to
Bandera Road are urgently needed and have been for decades, but the
road has languished with only a few minor improvements since the mid
'80s.
The problem has not been that officials haven't recognized
this need; there
have
been at least seven studies and proposals to upgrade Bandera Rd. over
the past three
decades. The snag has
been finding improvements that are amenable to the
City of
Leon Valley. A
flyover proposal by TxDOT back
around
1990 was shot down by Leon Valley leaders, and an alternative plan
that proposed building an elevated highway
along Leon Creek and bypassing Leon Valley altogether also was
nixed for various reasons. This schism has resulted in the repeated
stalling of efforts to make major improvements to Bandera Rd.
Then,
in 2009, the Alamo Area Regional Mobility Authority (ARMA) included
Bandera Rd. in their regional toll system plan.
The conceptual
proposal was an elevated tollway along the length of Bandera between
the loops. However, subsequent feasibility studies-- and simmering
opposition from several constituencies-- scuttled that plan. TxDOT
subsequently
took over studying other options to relieve congestion in the corridor.
In 2018, the City of San Antonio joined the effort and launched a
"community planning process" to develop a plan for transportation, land
use, urban design, and economic development along Bandera Road. The
first public meeting was held April 29th, 2019. The second round of
meetings is scheduled for mid-December 2019.
Elevated
throughway
("flyover") proposal
That
brings us to today. While this section is named the "flyover
proposal", TxDOT has actually been studying
a number of options to relieve congestion on Bandera Rd.; the flyover
option has simply become the most well-known and controversial of them.
Traffic study
In order to determine the best options for improvements, TxDOT studied
traffic patterns along the corridor and
identified three major traffic movements that need to be addressed:
- Through traffic:
Current studies indicate that about 9-15% of traffic on Bandera travels
from Loop 410 to Loop 1604. However, with continuing growth along
Bandera outside
Loop 1604, it is expected that percentage will increase.
- Local traffic: This
is traffic with origins and/or destinations in the Bandera Road
corridor (i.e. local residents and/or patrons of local businesses.)
- "Zig-zag" traffic:
This consists of traffic using a portion of Bandera for cross
connectivity between
a thoroughfare on one side of Bandera to another thoroughfare on the
other side of Bandera. Analysis of traffic data revealed that there
are three of these major
movements:
- Eckhert
- Mainland/Guilbeau
- Loop
410 - Grissom
- Loop
1604 - Prue
Major "zig-zag" traffic patterns
on
Bandera Rd.
These "zig-zag" movements create two unique problems:
- They
inject a large amount of traffic into the through route for a short
distance.
- They
generate massive left turn movements at multiple intersections. Left
turns are the most inefficient traffic movement and require
substantially more signal time, which then reduce the amount of signal
time available for opposing through traffic.
Options evaluated
With those
traffic patterns in mind, several options have been evaluated
to
date. These have included the following:
- Conventional widening:
This plan would add one lane in each direction to the existing lanes
(i.e. eight lanes from the Loop 410 ramps to Guilbeau and six lanes
from there to Loop 1604), make intersection improvements, and improve
access management (i.e. limiting driveways.)
- Superstreet/RCUT: This
would convert all intersections in the corridor to
"Restricted Crossing U-Turn" (RCUT) intersections. Additional through lanes could also be included in this
plan.
- Thoroughfare network improvements:
The City of San Antonio and TxDOT identified a possible future
Guilbeau-Eckhert connector route that would remove much of the
"zig-zag" traffic from the section of Bandera
between those intersections. The City has agreed to study this further
and has even listed it a possible future addition to its major
thoroughfare plan. A connector from Eckhert to Tezel by way of Silent
Sunrise has been in the thoroughfare plan for many years.
- Reversible connector: This
concept would build an elevated, reversible roadway to provide a direct
express lane for the
"zig-zag" traffic movement for traffic going between Eckhert and
Mainland/Guilbeau.
- Traditional freeway:
This would build a standard freeway corridor with mainlanes,
overpasses, ramps, and access roads. This proposal, however, would
require substantial additional right-of-way, which makes it extremely
expensive and disruptive; as a result, this plan is almost certainly
DOA.
- Elevated throughway:
This proposal, commonly-referred to as the
"flyover" plan, would consist of shifting the
existing lanes slightly further outward and building an
elevated roadway on piers located in the center median. This
elevated roadway, running from Loop 410 to Loop
1604, would overhang the surface lanes and consist of a
single lane and a shoulder in each direction to
carry through traffic, similar to the flyovers connecting Bandera and
Loop 410. Due to right-of-way constraints that limit possible
"touch-down" locations for
entrance and exit ramps, access points along the elevated section would
be very limited. The elevated lanes would tie-into the existing
flyovers connecting to Loop 410. There
are currently no plans for this road to be tolled.
While the
initial studies and modeling showed that, of the options listed
above, the elevated throughway provided the most benefit at reasonable
cost, it was determined
that none of the above proposals
individually provided more than limited, short-term congestion relief.
In addition to existing traffic volumes, there is an unknown‑‑ but
almost certainly quite large‑‑ amount of "latent demand", that is,
drivers who are using alternate routes to avoid the congestion on
Bandera. Improvements to Bandera would result in the return of many of
those commuters, overwhelming the improvements. Therefore, a
combination of some of the above‑‑ or possibly something else not
studied to date‑‑ is likely going to be needed.
As with previous flyover proposals, the current flyover option has
generated controversy in Leon Valley. Chief among the concerns of many
leaders and citizens there is that
a
flyover would speed
traffic through the suburb. This, it is asserted, would mean drivers
would
speed past the businesses along Bandera, thus negatively affecting
them. These businesses, of course, comprise an outsized portion of that
city's tax base, so their concern is understandable. (Of course,
congestion also negatively impacts those businesses, perhaps even more
than a flyover would.) Additionally, there is great
concern
about the aesthetics of an elevated road. These concerns specifically
are that it would be unsightly and create a visual
barrier that would divide the city and negatively impact property
values. There is also angst about the noise
that an
elevated road would generate.
Because
of these concerns, the City of Leon Valley asked TxDOT to suspend its
planning while it sought and evaluated other options.
Boulevard
proposal
In
a search for other possible solutions, Leon Valley enlisted
the
assistance of UTSA's Center for Urban and Regional Planning Research
and the Institute for Economic Development. After researching other
concepts, they developed a
proposal for what is known as a
"multi-way boulevard." As
envisioned, this would be a 10 lane at-grade thoroughfare with
signalized intersections in the same locations as today. The
10 lanes would include three
main through lanes in each direction with two parallel frontage lanes
on each side. The frontage lanes would be built in the area used today
for the drainage culverts on the side of the road and would be physically
separated from the
through lanes by landscaped traffic islands. Just like the
frontage roads along a freeway, the
frontage lanes in this concept would provide access to
adjacent properties and would be
the location for sidewalks, bus stops, and bike lanes. Depending on how
it is designed, traffic would move between the through lanes and
frontage lanes either at the intersections or, more
likely, via slip ramps between
intersections.
Cross-section of
proposed boulevard concept
There
are several examples of
multi-way boulevards in the US including Queens Blvd. and Ocean Pkwy.
in New York City, Octavia Blvd. in San Francisco, and Bothell Way in
Bothell, Washington. There is even a smaller-scale example here in San
Antonio:
Verano Pkwy. on the Texas A&M-San Antonio campus on the South
Side. All of these examples include on-street parking, however, which
the Bandera proposal almost certainly would not.
The
expected
benefits of the boulevard concept are as follows:
- By
isolating slower local traffic to the frontage lanes, traffic
in the through
lanes can move faster and more safely.
- With
10 lanes, the corridor would have about 66% more lane capacity than
today.
- The
boulevard would be landscaped with trees and other foliage, making the
corridor more pleasant and inviting especially for
pedestrians and cyclists.
- Because
there are no elevated structures, a boulevard would be much less
obtrusive than an elevated highway, thus minimizing visual and sound
impacts.
While the
flyover proposal
would require little if any additional right-of-way, the boulevard
proposal would almost certainly require some additional right-of-way,
although the exact amount has not yet been determined.
In
addition to traffic, access, and aesthetic considerations, UTSA's
Institute of Economic Development was asked to study the effect an
elevated road might have on property values. Unfortunately,
there's a dearth of direct data on the subject. However, data was
available
on the impact when elevated freeways were torn-down. This data showed
that doing so
resulted in a substantial increase in adjacent property values. Based
on that, UTSA's researchers extrapolated that building an
elevated
expressway through Leon
Valley would result in an equally inverse decrease in property values.
(COMMENTARY: That
seems
to be an overly simplistic inference as there are
many other variables and factors that would likely have played into
those
increases. To be fair, it would require much more extensive study to
identify and control for those factors. But it is also
well-known that improved access typically leads to an increase
in
property values. Furthermore, my own cursory
analysis of several random properties in the shadow of the
current
flyover in the vicinity of Bandera and Wurzbach show that almost all of
them have
increased in value over the past five years at roughly the same rate as
other properties further down
Bandera in Leon Valley. Again, to be fair, I was not able to compare
the property values immediately before and after the flyovers were
built nor to do an extensive analysis. In closing, normally, I would
present the study's findings without
editorial, but I felt these points needed to made. Your mileage may
vary.)
There is also evidence that increasing the walkability of an
area increases adjacent property values.
It
is important to note that, to date,
the boulevard concept is just that-- a concept. It has not been fully
engineered and vetted to ascertain traffic capacity, safety issues,
cost, and
other more technical considerations. Until that is done,
there's no way
to fairly compare this proposal to any of TxDOT's proposals. UTSA's
researchers
have admitted that the boulevard proposal, while adding capacity, is
not likely to solve congestion issues. Instead, it makes improvements
while further considering additional transportation modes, adjacent
land uses, and economic impacts. In conjunction with the boulevard
plan,
UTSA's team also emphasizes the need for expansion of other nearby
roadways as well
as the overall road network itself.
As
an interesting footnote, this is not the first time a boulevard plan
has been proposed as an alternative for this general corridor. A
proposal for a
Bandera/Culebra expressway in the 1970s was met by a counter-proposal
from San Antonio Mayor John Gatti for an "avenida", a concept described
as a wide boulevard with bus lanes.
Animation illustrating both the "flyover" and
boulevard proposals.
This is at Bandera
and Huebner looking north.
(Courtesy of UTSA and the City
of Leon Valley)
What's next
In 2018,
the City of San Antonio joined the effort and, in
conjunction with TxDOT and the
City of Leon Valley, began a "community planning process" to develop a
plan for transportation, land
use, urban design, and economic development for the Bandera Road
corridor. This will essentially reboot TxDOT's ongoing study.
The
first public meeting in this process was held April 29th, 2019. The
second round of
meetings is scheduled for mid-December 2019. This planning
effort is expected to run through 2022. More details are available at
the following sites:
Renderings
Below are selected renderings created by UTSA of both the
flyover and boulevard proposals. These
renderings are only for illustrative purposes and don't represent any
actual plans. A
sincere thank you goes to the UTSA
Center for Urban and Regional Planning Research and the City of Leon
Valley for making these available.
Bandera and Seneca: Flyover
Bandera and Seneca: Boulevard
Bandera and Seneca: Flyover
Bandera and Seneca: Boulevard
Bandera and Huebner: Flyover
Bandera and Huebner: Boulevard
Bandera and Huebner: Flyover
Bandera and Huebner: Boulevard
Bandera and Eckhert: Flyover
Bandera and Huebner: Boulevard
FAQ
Below are some frequently-asked questions and comments about this
corridor.
Why can't they just
synchronize the traffic signals on Bandera? This would fix the problem.
Actually, the signals on Bandera are already part of a coordinated
system and are optimized. Many people think that just synchronizing
(coordinating) signals is a magic solution to all congestion. While in
many situations it can and does provide substantial benefits, the fact
is that coordinated signals
can only provide improvements up to the point where traffic volumes on
a road reach the saturation point, and then the laws of physics (space
and time) take over. Bandera well exceeds the saturation level at many
times of the day.
The
way that signal coordination works is by breaking traffic
into groups ("platoons") and moving them through the corridor at a set
speed so that they hit each signal green along the way. The
gaps between platoons are then used to allow green time for
cross-traffic and left turns. When traffic volumes on a
roadway reach saturation, the number of vehicles is greater than a
reasonable amount of green time at each intersection can clear on each
cycle.
Then more vehicles stack up behind those as the gaps
between platoons fill-up with vehicles turning onto Bandera
from
cross streets and driveways. On many urban arterials, the volume of
traffic turning onto and off of a specific roadway at each
intersection often is fairly balanced, so the platoon gaps stay
somewhat stable and therefore signal coordination works better. But the intersecting
road network along the Bandera
Road corridor doesn't allow this and instead forces high volumes of
traffic to turn onto Bandera at one intersection and then
leave Bandera at a downstream intersection (see
the map near the top of this page.) These
"interlopers" consume most
or all of the green time at the next downstream signal that was
intended for the next platoon of through traffic to use. This
results in part or even all of the following platoon getting stopped,
making it
seem like the signals aren't synchronized. With each cycle, the process
repeats and the backups compound.
Here's
another way of explaining it. Imagine the signals on
northbound Bandera at Grissom turn green and about 100
vehicles go
through before it turns red again. We'll
call this "Group 1". As those vehicles approach the Poss intersection,
the signal turns green and stays green long enough allow those 100
vehicles through before turning red again,
and so
on for each intersection downstream. The process repeats then with
Group 2, 3, etc., and everything is good.
Now imagine that after
Group 1 goes through the Eckhert intersection and the light turns green
for Eckhert, 50 vehicles turn onto Bandera. They'll get
stopped at
Mainland when
the light turns red behind Group 1, so there are now 50 vehicles
waiting at Mainland. When the 100 vehicles in Group 2 reach that
intersection, there will then be 150 vehicles wanting to get through,
but
since the signal is timed for a platoon of about 100, the 50 who
arrived earlier from Eckhert will go and
then only about 50 vehicles from Group 2 will make it through, leaving
the last 50
waiting. Then, behind them, 50 more vehicles turn onto Bandera from
Eckhert. That 50, plus the 50 from Group 2 that didn't get through,
means there will then be 100 vehicles waiting at Mainland. Then the
next 100 vehicles
from Group 3 arrive, and now there are 200 vehicles wanting to get
through at Mainland, but only the first 100 (the 50 leftovers from
Group 2 and the 50 from Eckhert) will get through, meaning none from
Group 3 will make
it through
For those in Group 3, it now seems like the signals aren't
synchronized since they have to stop and wait through a cycle. But it's
not because the signals aren't synchronized that they didn't get
through, it's because additional traffic usurped their "slot" at
Mainland. And as you can see, with every cycle, those numbers
will keep compounding until the volume of traffic entering the corridor
decreases below capacity.
So
couldn't they just extend the green time at Mainland to account for the
additional vehicles from Eckhert? Sure, up to a point, but not much
because doing so increases the red time on Mainland and for the
southbound left turn, and longer red time of course means additional
delays and
congestion on those approaches. And this example was only demonstrating
how
just one intersection can inject enough traffic to break the
synchronization. Don't forget that even more traffic is going to turn
onto Bandera from Grissom, Poss, Huebner, and the many driveways along
the way, so each subsequent intersection downstream would need to have
progressively more green time to accommodate each additional cohort of
interlopers. This would eventually result in the downstream signals on
Bandera
having to be green constantly or nearly so in order to allow all that
traffic through. That is obviously not a realistic solution.
Alternatively, less
traffic could be allowed through the Grissom intersection to offset the
traffic turning on at Huebner and Eckhert, but that would just cause
even longer
backups there and therefore is also not practical.
This example shows the limitations of signal coordination. When this
situation
happens,
the traditional solution is to upgrade the corridor to a freeway.
Why did they build the
flyovers at Loop 410? They don't really help and were a waste of money.
As is often the case, this perspective ignores the bigger picture. The
flyovers at Loop 410 take the heaviest traffic movement at that
location and remove it from two already-congested signalized
intersections. While
traffic coming from Loop 410 to Bandera regularly backs-up during the
afternoon rush hour, it does so out of the way of the surface
intersections. More importantly, before the flyovers were built, that
traffic nearly always backed-up onto the Loop 410 mainlanes, which was
a dangerous situation. Now, that traffic is stored safely out of the
way. Meanwhile, traffic headed the other way enjoys a good five minutes
or more of time savings during the morning rush hour. If and when
Bandera through Leon Valley is improved, commuters going from Loop 410
to Bandera during the afternoon rush hour will enjoy the full potential
benefits of the existing flyover. While congestion at that location may
make it seem like the flyovers don't help, the point that's often
forgotten is this: how much worse would the congestion there be without
the flyovers?
The existing flyovers
have caused several nearby businesses to go under.
I am only aware of one business that has claimed it was harmed by the
flyovers. Regardless, there is no objective data (to my knowledge) to
support
that claim. It could have been a case of that business already having
difficulties that were exacerbated by the traffic changes, or,
perhaps, the flyovers are being used as a scapegoat. The other
established businesses in the area seem to be doing fine. Regardless,
congestion is at least equally detrimental to businesses if not more
so, so improvements need to be made. While nobody wants to see
businesses fail, there will, unfortunately, always be trade-offs
whenever a major change is made, and attempts are made to minimize
those
impacts.
Traffic has been bad on
Bandera for decades-- why hasn't anything been done?
As mentioned above, several attempts have been made over the years to
improve Bandera, including
adding flyovers at major
intersections and an elevated tollway, but the City of Leon Valley
vetoed all of the proposals due to fears that those plans would hurt
local
businesses, which would have a serious impact on the city. New
leadership in Leon Valley in
recent years has recognized the need for improvements and has indicated
a willingness to find solutions, but there's still a long road ahead
(pun intended.) A new comprehensive planning effort that includes TxDOT
and the cities of Leon Valley and San Antonio is now underway.
Acknowledgments
Special
thanks to
the following for their assistance in providing information about these
proposals:
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information
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