Home | About me | Contact | What's new | Privacy | Search

San Antonio
Freeway system
  Fwy system history
  2017 traffic statistics
  The freeways
    I-10 East
    I-10 West
    I-35 North
    I-35 South
    Kelly Pkwy
    Loop 410 (I-410)
    Loop 1604
    SH 151
    Spur 371
    US 90 West
    US 281 North
    Wurzbach Pkwy
  Construction projects
    I-10E Expansion
    I-10E/Loop 410
    I-10 Boerne area
    I-35 Comal Projects
    I-35 NEX
    LP 1604 North
    LP 1604/Bandera
    LP 1604/Bndra-Hsmn
    LP 1604/Blanco
    LP 1604/Bulverde
    LP 1604/FM 78-I-10
    LP 1604/I-35-FM 78
    LP 1604/Marbach
    LP 1604/Potranco
    SH 151 Expansion
    SH 151/LP 1604
    SH 151/Loop 410
    US 90W Expansion
    US 90/Loop 410
    US 281 North Exp
    US 281/Basse
    US 281/Jones-Mltsbrg
    Wurzbach/NW Military
    HOV lanes
    Media galleries
    Tollway system
    10/1604 yield signs
    History of 281/410
Other roads

Search this site
This site is not affiliated with any official agency.





San Antonio Area Freeway System
PROJECT INFO: Loop 1604 from Potranco to US 90

This page last updated April 23, 2019


Project locationLocation
Loop 1604 from Potranco Rd. to US 90

Under construction (83% complete)

This project will upgrade Loop 1604 at this location from a four-lane divided highway to a four-lane, toll-free expressway. This includes adding
an underpass at Dove Canyon/Falcoln Wolf, expanding the existing overpass at Marbach, and adding continuous access roads and entrance and exit ramps. The expansion will be completed by converting the existing northbound lanes to the northbound access road, converting the existing southbound lanes to northbound expressway lanes, and constructing the remaining lanes (southbound expressway and access road.) Unbeknownst to most motorists, the existing divided highway was orignially designed to eventually be expanded to an expressway as described above; this will expedite the work a bit, reduce the project's cost, and minimize disruption to traffic.

This project is also building a direct connector (flyover) from SB Loop 1604 to EB US 90 and the existing cloverleaf ramp from southbound Loop 1604 to eastbound US 90 will be removed. The existing signalized intersections at US 90 will remain, but a second overpass for Loop 1604 over US 90 has been built for the northbound lanes and the previously-existing overpass is now used for the southbound lanes. The divided highway now endd just south of US 90 and merges into the existing two-lane road.

The cost of this project is $64.1 million and is being paid for with local funds from the Alamo Regional Mobility Authority as part of the larger $825 five-year regional transportation plan announced in January 2014.

A separate project on US 90 converted the US 90 access roads to one-way and built the turnaround from westbound to eastbound US 90 at Loop 1604, which should remove an appreciable amount of traffic from the intersections at Loop 1604.

How this project will help
Staggering ongoing growth in this area of San Antonio necessitates upgrading this roadway. The new expressway lanes with overpasses at the currently signalized intersections will allow for continuous free-flowing traffic through the corridor. The four expressway lanes are anticipated to handle the projected traffic in this corridor for the next 20 years. The connector to US 90 will remove that traffic from the remaining signalized intersections at US 90. 

Construction began in early 2017 and estimated completion is mid 2019. Click here for the latest status.


  • Why was the crossover at Emory Peak removed? Nobody told us when we moved here it would be removed someday.
    It was always planned for that crossover to be temporary and be removed when Loop 1604 was expanded. The developer of the Laurel Mountain Ranch subdivision was aware of this and should have informed buyers.

  • There was already a crossover at Emory Peak. Why close it and add a new crossover at Falcon Wolf/Dove Canyon where there wasn't one previously?
    In a freeway corridor, one mile is generally considered to be the ideal interval for crossovers. When crossovers are closer than that, it complicates entrance and exit ramp placement and shortens weaving areas or forces some traffic to traverse an additional signalized intersection, all of which decreases safety and increases congestion and motorist inconvenience. Emory Peak is located just 1/2 mile from Marbach whereas Falcon Wolf/Dove Canyon is located at just about one mile from Marbach and a little over one mile from Potranco; in other words, it's more ideally located for a crossover. Furthermore, the 
    Falcon Wolf/Dove Canyon location connects a roadway on both sides of Loop 1604, also a more ideal situation. Were it not for the steep elevation differences there, a crossover would have been built there many years ago. Finally, it is planned for Falcon Wolf to eventually extend to Marbach on the east (and it essentially already does now via Big Wolf Creek) and for Dove Canyon to eventually extend to Grosenbacher via American Lotus on the west, thus making it a future east-west thoroughfare and making the overpass at Loop 1604 more logical. In other words, the overpass at Falcon Wolf/Dove Canyon is one important piece of a puzzle that's still being put together.

  • Why are the new sections of Loop 1604 only four lanes? It needs to be six lanes or more.
    The number of lanes for a new roadway is based on current and projected traffic volumes for the next 20 years. Twenty years is the accepted planning horizon for a couple of reasons. First, that's the length of time before a road will need major repairs and upgrades simply due to age (i.e. the road's expected lifespan). Second, that length of time is the longest that any projections can be considered even remotely reasonable. Since nobody has a crystal ball, traffic projections are "educated guesses" based on the best data available for future development in an area and past growth. Roads are then planned based on those projections. In the case of the new segments of Loop 1604, those projections show that four lanes will be adequate for the 20 years. TxDOT, as a steward of taxpayer dollars, cannot spend more than they can justify, a policy I'm sure most taxpayers support, especially with all the other needs that need to be funded.

  • Is the one-way access road at the eastbound US 90 exit to Loop 1604 permanent? If so, why?
    This has been a heated topic of conversation especially among residents of the Canyon Crossing subdivision off of Cagnon Road southwest of the US 90/Loop 1604 intersection. The answer is yes, this is a permanent change. The reason why is simple-- safety. One-way access roads have been proven to reduce crashes dramatically. In this case especially, the left turn onto Cagnon was fairly close to the exit from US 90. Therefore, high-speed traffic exiting from US 90 was quickly in a conflict with that left-turning traffic. Furthermore, one-way access roads are much more efficient from a traffic-carrying perspective-- an important consideration in a growing area. A future expansion project on US 90 will extend the access road to the west, which could help mitigate the impact of this change. (Note that this change was actually not done as part of the project discussed on this page, but I've addressed it here because this page covers ongoing construction at this location.)

Click on the image below to open the detailed schematic for this project from TxDOT with my own annotations added to help clarify and explain the various elements. The schematic will open in a new window that you can scroll and zoom.

 (Note: The schematic below are somewhat large and may take a few seconds to open.)


Other sites of interest
TxDOT - Loop 1604 from US 90 to FM 1957 (Potranco Road)

If you found this informative, please consider making a small donation to help support it. Thanks!
This page and all its contents are Copyright 2019 by Brian Purcell

The information provided on this website is provided on an "as-is" basis without warranties of any kind either express or implied.  The author and his agents make no warranties or representations of any kind concerning any information contained in this website.  This website is provided only as general information.  The author expressly disclaims all liability with respect to actions taken or not taken based upon the information contained herein or with respect to any errors or omissions in such information.  All opinions expressed are strictly those of the author.  This site is not affiliated in any way with any official agency.