In October 2009, with plans for the US 281 superstreet nearing completion, the Bexar County Commissioners Court approved funding to study a possible superstreet in the Loop 1604 West corridor, specifically between Braun Rd. and SH 151, as a possible interim solution to ease congestion while the Alamo Regional Mobility Authority (ARMA) completes an environmental study on possible long-term improvements.  The superstreet study, completed in early 2010, showed that a combination of improvements along that section of 1604 would provide substantial improvements.  In May, ARMA previewed the initial designs and expected benefits.  Under the plan, the intersections of New Guilbeau and Shaenfield will be reconstructed as superstreet intersections.  This will eliminate the left-turn movements from those roadways onto Loop 1604.  Instead, traffic wanting to turn left will turn right first, then use downstream turnarounds on 1604 to complete the left hand turn.  While the plan does add additional signals and forces some drivers to travel out of their way, the plan is expected to reduce overall congestion in the area because it will reduce signal cycles at each intersection from four phases to just two, thus allowing substantial additional green time for 1604 traffic.  It is estimated that by doing so, travel speeds could be increased by 36% and delays reduced by 69% during the morning peak and that average travel speeds could be increased by 65% and delays reduced by 79% during the evening peak period.

In addition to the superstreet intersections mentioned above, additional improvements are underway that include the following:

• Restriping Loop 1604 to three lanes in each direction at Braun to increase throughput at the Braun intersections.  (Complete!)  A limited number of future improvements to improve traffic on Braun itself are also being considered, including adding an additional westbound lane on Braun (Complete!)
• Re-structuring the Loop 1604/SH 151 intersection to eliminate the left turn from southbound 1604 onto SH 151.  Instead, traffic headed to 151 will exit 1604 on a new ramp just south of Culebra and use an improved southbound access road, then cross Loop 1604 at a perpendicular intersection.  This will also facilitate traffic coming from Alamo Ranch Pkwy.  Although this will add another southbound traffic signal on 1604, it will provide substantial benefits by eliminating the weaving of traffic entering from Culebra and by eliminating left turn lane overflow and "friction" on the mainlanes at that location.  Doing so is expected to provide an astounding 85% reduction in morning peak delays and a 47% reduction in delays during the evening rush hour.  This change also lays the groundwork for a future SH 151 underpass (see next bullet.)  (Complete!)
• Constructing an underpass on SH 151 under Loop 1604 to connect to Alamo Ranch Pkwy.  This project had been rolled into the Loop 1604 tollway plans, but has since been extracted and will be built separately.
• In conjunction with the superstreet project, the City of San Antonio is also looking to accelerate plans to extend Shaenfield from Loop 1604 east to Weybridge St. near Burke Elementary School to improve access to and from Northwest Crossing.  The Shaenfield superstreet intersection will therefore be built as a four-legged intersection to accommodate that future extension.
   

Despite the spin by some politicos from the area, all of these proposals are short-term or interim "band-aid" solutions until the environmental studies, funding sources, and any associated legal wrangling for a more substantial upgrade of Loop 1604 are resolved over the next several years.

These projects (not including the Braun intersection improvements or SH 151 underpass) were estimated to cost $7.7 million to build, but came in substantially cheaper at $5.7 million.  Funding came from several sources including federal economic stimulus funds, MPO metro mobility funds, Bexar County, the Advanced Transportation District (primarily from VIA), and TxDOT in-kind donations. 

Construction on the superstreet intersections and first phase of the SH 151 intersection improvements began in early 2011 and should be completed by the end of the year.  See that status section below for the latest updates.

This will be the second superstreet in Texas, with US 281 North being the first.  A third superstreet is being planned in Austin.

On this page:

• How a superstreet works
• Project schematics
• Project status
• Other sites of interest

How a superstreet works

For details on the general concept of a superstreet and how it works, see the superstreets page.

Project schematics

(Schematic links are below)

Click on one of the links below to see an annotated preliminary engineering schematic for each intersection.  These schematics are courtesy of ARMA and are subject to change.  Annotations are my own.  Note that the schematics may be wider than your screen; be sure to scroll to see the entire diagram.

• New Guilbeau Rd. (Complete!)
• Shaenfield Rd. (Complete!)
• SH 151/Alamo Ranch Pkwy. (Complete!)

Full schematics can been downloaded from ARMA's website (see link below.)

TxDOT has completed work on the Braun intersection improvements resulting in a remarkable improvement in traffic flow.  The superstreet improvements at New Gilbeau, Shaenfield, and the improvements at SH 151 began construction in March 2011.  The New Gilbeau intersection went online August 18th followed by the Shaenfield intersection on September 15th.  The SH 151 intersection improvements went online on November 2nd.  Construction on the SH 151 underpass is expected to begin in early 2012.

	Alamo Regional Mobility Authority - Loop 1604 Super Street project http://www.alamorma.org/1604SuperStreet.html
	On The Move Blog - Loop 1604 "super-street" previewed http://www.onthemoveblog.com/2010/06/loop-1604-super-street-previewed/