The Texas Transportation Commission approved increasing the speed limit to 75 mph on about 1,500 miles of mostly-rural Interstate highways in the state.  Around the San Antonio area, the following stretches will see 75 mph signs soon:

• I-10 West from Loop 1604 to past Kerrville (where it’s already 80 mph)
• I-10 East from just outside Loop 410 to Waller County west of Houston
• I-35 South from Palo Alto Rd. to the existing 75 mph section south of Devine
• I-37 from just inside Loop 410 to Corpus Christi

I-35 between San Antonio and Austin was not approved for the higher speed limit.

The Legislature approved the higher speed limits last year.

More information

• TxDOT’s 75 mph page – http://www.txdot.gov/safety/speed_limit/75mph.htm

In San Antonio and across Texas, there has been a rash of wrong-way drivers (WWD) over the past few years.  In San Antonio last year, there was a WWD about every other day.  Fortunately, 80% of those drivers caused no accidents.  But sadly, seven people were killed by WWDs last year.  Of no surprise was that the majority of WWDs were intoxicated.

To combat the problem, several agencies formed the San Antonio Wrong Way Driver Task Force in March 2011.  Those agencies include TxDOT, SAPD, City of San Antonio Public Works Department, Bexar County Sherrif’s Office, and Texas Transportation Institute, and the Federal Highway Administration.  The task force worked to determine the extent and characteristics of the local problem, evaluate previous research and countermeasures, and formulate a plan to test and implement countermeasures locally.

After crunching the data, it was determined that the most WWD incidents occurred between midnight and 6am with Saturday night/Sunday morning being the worst by far (nearly twice that of Friday nights, which was the second most dangerous.)

In determining the worst locations, engineers found that it was nearly impossible to ascertain the exit ramp where the WWD entered.  In fact, the wrong way entry point could be identified in just five cases last year.  Furthermore, focusing on specific ramps limited the effectiveness of the evaluation of the issue or any subsequent countermeasure programs.  Therefore, the problem was scoped by corridor.  In that context, the US 281 corridor from downtown to Stone Oak showed the most WWD incidents.

Next, the group evaluated potential countermeasures.  One of the first suggestions made by the general public is the use of wrong-way spike devices like those used in parking lots.  However, previous research and testing has shown that these devices are not the obvious panacea many folks think them to be.  Here are some of the problems noted in the task force’s report:

• Such devices are only designed for low-speed locations (< 10 mph).
• When tested in a high-speed location, even after being modified, the spikes did not cause the tires to deflate quickly enough to prevent the vehicle from entering the freeway and making significant progress.
• During testing in a high-speed location, the spikes often broke, making the device useless for its intended purpose and, furthermore, damaging the tires of vehicles headed in the right direction.
• Many right-way drivers perceived the devices as a hazard and hit their brakes, thus creating a hazardous condition.
• The devices were slippery during wet weather.
• Dirt, debris, and ice build up in the devices, preventing the spikes from folding down properly for right-way drivers.

Not mentioned in the report is the fact that even if spikes worked as intended, that would leave a disabled vehicle in the middle of an exit ramp, most often in the dark, thus presenting a serious traffic hazard for other drivers.

Given all these factors, spike strips are just a bad idea all around.

San Antonio is not the first city to encounter this problem, and therefore other countermeasures were available for evaluation.  One of the first things looked at was enhanced static signing.  TxDOT has already developed a checklist for increasing the visibility of static wrong-way signage and markings and has implemented that scheme on most ramp locations in San Antonio.  They are now considering additional “supplemental” measures including oversized signs as needed.

SAPD currently relies almost exclusively on the public to report WWDs.  All but one of the WWD incidents last year was first reported by the public (the other one was observed by a TransGuide operator.)  To improve the detection of WWDs, various detection devices can be employed.  These can be installed on exit ramps as well as on the main lanes and can alert SAPD and TransGuide dispatchers within seconds of a WWD being detected.

Also evaluated were “active” warning signs that either light-up or flash red borders when activated by a detection device.  These can also be placed on exit ramps and/or the main lanes.

Finally, physical channelization (i.e. the use of traffic islands to shunt traffic in the proper direction) on frontage road driveways was evaluated.

To determine the effectiveness of these devices, TxDOT selected the US 281 corridor from downtown to Stone Oak for a test project.  Wrong-way detection devices and active signage will be placed on each exit ramp in the corridor as well as at four main lane locations: south of Encino Rio, south of Thousand Oaks, south of Loop 410, and north of Hildebrand.  In addition, TxDOT will continue their practice of putting WWD warnings on the TransGuide dynamic message signs.  After the devices are installed, the effectiveness of these measures will be evaluated.  Work has already started and the system is expected to go online in mid February 2012.  Design work on a second corridor– I-35 from US 90 to I-37– is underway.  Because of the unique features of that corridor, including double-decked sections and non-typical exit ramps, different countermeasures may be employed.  Depending on the outcome of these projects, the system may be expanded to the rest of the city’s freeway system.

Hopefully, these countermeasures prove effective at solving a problem that is simply getting out of hand.

More information

• The San Antonio Wrong Way Driver Initiative

UPDATE (11/1/11) - The changeover has been postponed until Wednesday.

Just back from vacay and have some local news to report.  The final element of the package of improvements along Loop 1604 West that included two superstreet intersections will come online tomorrow.  Namely, the left turn from southbound 1604 to SH 151 will be eliminated.  Motorists wanting to go to SH 151 will now exit at a new exit ramp just south of Culebra, follow the access road, then cross 1604 at a perpendicular signalized intersection.  The existing entrance ramp from Culebra will be closed and replaced by an improved entrance ramp at the SH 151 intersection.  (For a schematic of these changes, see the link under “Additional information” below.)

Like the superstreet intersections, this change will most likely seem completely unintuitive for many folks.  After all, southbound Loop 1604 traffic will now have to stop to allow traffic to enter SH 151 whereas before they didn’t ever have to stop.  But this new arrangement will actually be safer overall and will help reduce congestion in the area.  The reason is that most of the traffic coming from Culebra moves over to the left to make the turn onto 151.  This causes lots of conflicts with through traffic on 1604, thus creating an unsafe free-for-all and lots of resulting congestion, not to mention the resulting driver angst.  Moving all that traffic onto the access road (which has been improved to handle it) will eliminate that mess.  Yes, southbound 1604 traffic will now be stopped periodically to allow traffic to cross over to 151, but it will be better controlled now, which will improve safety.  And there are some things that will mitigate the delay to southbound 1604 traffic: 151-bound traffic will now be moving straight, so it can move a little faster than it did when turning left; there will be three lanes crossing 1604, thus improving throughput by 50%; and the signal can be synchronized to minimize the disruption to southbound platoons of vehicles coming from Shaenfield.  Computer modeling of these changes showed an astounding 85% reduction in morning peak period delays and a 47% reduction in the afternoon over current levels.

The change is also considered a necessary preparatory change for the upcoming SH 151 underpass at Loop 1604.  That left-turning traffic will need to be moved out of the way to facilitate that anyway, so doing it now will help expedite that project when it starts next year.

Finally, the changes will have some ancillary benefits including allowing traffic from Alamo Ranch Parkway to reach SH 151 and allowing traffic headed to Alamo Ranch from southbound 1604 to bypass the congested Culebra intersection, both of which should reduce the congestion in that intersection a bit.

The previous improvements along Loop 1604 have already resulted in a dramatic reduction in congestion.  As I have previously reported, the simple addition of an auxiliary through lane at Braun virtually eliminated the peak period backups there.  Since then, the superstreet intersections at New Gilbeau and at Shaenfield have turned a chronically-congested stretch of 1604 into free-flowing, even in peak periods.

Additional information:

• Loop 1604/SH 151 improvements schematic
• Loop 1604 West Superstreet

The biggest quake around here before today’s was in 1993.  Long-timers may remember that just a few days before that quake, inspectors had found some cracking in a pylon supporting the then-new upper deck of I-10 near Woodlawn.  There was briefly some concern that the quake may have done additional damage.  Fortunately, that wasn’t the case and the column was subsequently retrofitted with some additional tension rods.

I checked with the folks at TxDOT and they tell me that they sent inspectors out after today’s quake to look at the bridges on state highways in Atascosa County.  Everything checked-out fine.

Local TxDOT officials joined with several dignitaries yesterday to cut the ribbon on a project that widened Loop 1604 near Randolph AFB.  The 17 month, $6.6 million project upgraded 2.5 miles of Loop 1604 from a two-lane “farm” road to a four-lane divided highway.  The project came in on-time and under budget.

Speakers at the ribbon-cutting included US Representative Henry Cuellar.  Cuellar helped secure the federal economic stimulus funding to get the project off the ground.

This section of the loop has been in the news recently.  A project to continue the expansion from its current terminus at Lower Seguin Road to I-10 is planned to start next year.  However, county officials had briefly considered transferring funding from that project to construct the northern set of ramps at US 281 and Loop 1604.  An alternative source of funding was found, however, thus allowing the widening project to continue as planned.

It’s worth noting that this expansion mirrors a similar expansion done on Loop 1604 West nearly two decades ago.  Road improvements tend to be incremental or evolutionary.  The road system San Antonio has today didn’t just drop out of the sky one day.  The project dedicated yesterday upgraded a congested and dangerous two-lane road to a four-lane divided highway with traffic signals.  This configuration is a substantial improvement over the previous road and is more than adequate for the current needs and for those in the foreseeable future, just as the expansion of Loop 1604 south of Braun Road was back in the ’90s.  Will traffic growth eventually render this roadway obsolete?   Maybe.  But building a full-fledged expressway at this location now is unnecessary and would have been an injudicious use of scarce funding, just like doing so out on Loop 1604 West back in the ’90s would have been.

If you’re observant, you’ll notice that there have also been left turn lanes built from southbound Loop 1604 that seem to go nowhere and a second turnaround north of Shaenfield that seems to serve no purpose.  Those have been built in anticipation of a future extension of Shaenfield to the east.  The City of San Antonio is currently in the planning stages for that.

The superstreet intersection at Loop 1604 and New Gilbeau opened about a month ago and has provided a noticeable reduction in congestion.  The final element of the current package of improvements along that stretch of Loop 1604 will make changes the SH 151 intersection; it’s due to be completed later this year.  An underpass for SH 151 at Loop 1604 is slated to begin construction next Spring.

RELATED SITE:

• TexasHighwayMan.com – Loop 1604 Superstreet Project

Officials have released a list of the 100 worst traffic conditions in Texas.

Dallas motorists suffer the most highly congested road conditions in Texas, says a recent report from the Texas Department of Transportation.

The state’s top three bottlenecks are all located in Dallas County, according to the 100 Most Congested Roadway Segments in Texas. But while Dallas has the hottest spots, Harris County actually has more of them. The Houston area has 31 on the worst road conditions traffic list while Dallas has 21.

Road conditions for Fort Worth are next in line for headaches, with 15 tight spots, followed by San Antonio with 11 and Austin with 10.

Here are the top 10 most congested roads and their respective counties:

1. SS 366 in Dallas, from I-35E to U.S. 75
2. I-635 in Dallas, from I-35E to U.S. 75
3. U.S. 75 in Dallas, from I-635 to Woodall Rodgers Freeway
4. I-35 in Travis, from SH 71 to U.S. 183
5. I-35W in Tarrant, from I-30 to SH 183
6. U.S. 59 in Harris, from I-10 to SH 288
7. I-35E in Dallas, from I-30 to SH 183
8. I-10 in Harris, from I-45 to U.S. 59
9. I-610 in Harris, from I-10 to I-45
10. I-45 in Harris, from I-10 to I-610

See this interactive map to locate all 100.

Congestion patterns haven’t changed much over the past year, Texas officials say. 

“Finishing or starting construction is probably the number one reason for the shift in ratings,” said Tim Lomax, a researcher with the Texas Transportation Institute, which helped TxDOT develop the list.

“Weather contributed, and the economic recession has generally reduced congestion compared to four years ago,” he said. “But in the last year, construction was primary.”

The Transportation Institute calculates congestion from traffic speeds gathered by NAVTEQ, a firm that collects real time travel information nationwide, and combines that with traffic volume data.

“Texans know that traffic is bad, and these ratings shifts won’t change public opinion,” Lomax said. “The list is important for planning purposes.”

It’s been 30 years in the making.  Today, local officials gathered at Walker Ranch Park to officially break ground on the final section of the Wurzbach Parkway.  The segment, from West Ave. to Jones-Maltsberger, is actually already under construction, along with the two adjacent segments.  When they’re completed in 2014, the long-awaited east-west thoroughfare will finally be complete.

Speaking at today’s groundbreaking were the Wolffs (Nelson and Kevin), Lyle Larson, local TxDOT district engineer Mario Medina, and TxDOT’s new interim executive director John Barton.  Somewhat surprisingly, there was little media coverage of the event; only KABB and KTSA had stories on it.

For more information about the three current projects, see my site here:
Texas Highway Man – Wurzbach Parkway

If you have a lead foot, then you’ll love this news.

First, if you hadn’t heard already, the Legislature earlier this year approved– and the governor signed– a bill that would raise the statutory maximum speed limit for state highways to 75 mph (excluding, of course, the existing 80 mph speed limit on some sections of I-10 and I-20 out in West Texas.) Texas now joins all but a handful of states west of the Mississippi with a 75 mph top speed.  The limit can only be increased on roads where an engineering study determines that it’s safe to do so, but if past practice holds true, that should be the majority of roads that are currently capped at 70 mph.

Even better, the bill finally eliminates the matrix of speed limits for daytime/nighttime and cars/trucks.  All speed limits will now apply to all vehicles at all times.  Texas was the only state to still have a different nighttime limit and one of the few with a separate limit for trucks.

The new law takes effect September 1st.  A separate effort to increase the maximum speed to 85 mph died.

More recently, the speed limit on the northern arc of Loop 410 has gone up from 60 mph to 65 mph.  With the recent completion of construction to widen the freeway to 10 lanes, TxDOT completed a speed study that showed the 85th percentile speed being 65 mph, so in accordance with agency engineering guidelines, TxDOT asked the City of San Antonio to officially increase the speed limit to 65 mph north of US 90.  Signs went up this past week.

I also recently noticed that the speed limit along Loop 1604 south of Braun Rd. increased from 55 mph to 60 mph.

Starting tomorrow morning, traffic coming from New Gilbeau will no longer be able to turn left onto Loop 1604 southbound. Instead, all traffic will turn right with those wishing to go southbound then taking the new turnaround about 1,500 feet downstream. Traffic headed southbound on 1604 will still be able to turn left onto New Gilbeau.

This is the first of two superstreet intersections to be built on Loop 1604 West. The second one, at Shaenfield Road, is expected to be completed next month.

The new configuration at New Gilbeau will allow one signal phase to be dropped. This will allow additional green time to be added to Loop 1604 northbound without lengthening the overall cycle length. The improvements at New Gilbeau will not provide any direct benefit to motorists on southbound 1604. However, the improvements at Shaenfield will be the inverse of those at New Gilbeau; that is, it will benefit southbound traffic but not northbound.

The final elements of this package of improvements will re-configure the intersection of SH 151 and Loop 1604. That will be completed later this year. Work is scheduled to start in mid 2012 on an underpass for SH 151.

This is the second stretch of superstreet in San Antonio. The first, on US 281 north of Loop 1604, was completed last October. A before-and-after study showed a 25% increase in morning rush hour speeds and a 50% increase in evening rush hour speeds.

PREVIOUS POSTS

• Loop 1604 superstreet approved
• Loop 1604 “super-street” previewed
• Loop 1604 “super-street” approved
• Loop 1604 “Super Street” to be studied

RELATED LINK

• TexasHighwayMan.com – Loop 1604 West Superstreet