Great northern photo Judging from last night's meeting at Gullett, it is anybody's guess as to whether sound walls will be going up along Great Northern. Even though people at the meeting could ask about any of the sections along MoPac being considered for sound walls, the majority of the 25 to 30 people at last night's meeting were interested in the two segments along the Great Northern Blvd.

By way of background, sound walls are part of the Environmental Study phase of the MoPact Improvement Project. The objective of the MoPac Improvement Project, according to the project overview on its website,, "is a combined effort from the Central Texas Regional Mobility Authority, the Texas Department of Transportation (TxDOT), the City of Austin and Capital Metro to address traffic congestion on the 11-mile stretch of MoPac between Parmer Lane and Cesar Chavez Street."

Wall along great northern Last night's meeting at Gullett was one of seven sound wall workshops that the MoPac Improvement Project Team has scheduled with various neighborhoods to provide background information about the project including results of their noise studies, where the walls are being proposed, and height of the walls. The Project Team had mailed letters to property owners adjacent to the proposed walls, "the benefitted property owners," notifying them about the workshops. The benefitted property owners are the ones who get to vote on the walls. If a majority of these property owners vote for the wall, it will be built. They have until Monday August 29, 2011 to submit their ballots.  

What follows are notes from the meeting posted to the Allandale listserve this morning by Michael Nink that provide a nice summary of what was presented at the meeting and what Michael learned in talking with the Project Team regarding the wall envisioned for the two segments along Great Northern. I am cross-posting this to the website with Michael's permission.

I attended the Great Northern Blvd Sound Wall workshop Thursday night and found the workshop to be very informative and educational.The MoPac Improvement Project team did an excellent job of making sure all the neighbors ’questions were answered.

Here are a few things that I learned that I could not find on the website for the project.

1. The wall height is going to vary between 8'’ to 20'’ high. 100% of Great Northern from Far West to Foster will be a 20'’ wall; Far West to White Rock will vary from 20'’ to 18’' to 16’' etc. Close to White Rock the height decreases to the point of 8' to 12'’ for those homes that back directly up to the railroad south of White Rock. 20'’ is a tall wall; below I placed a link to some pictures from the night and I have one from the inside the auditorium at Gullet where they marked off the various heights of the wall starting at 8' ’and going to 12'’ which was the height of the room. Basically you would need to double the size of the wall to reach 20’ and I included a 5’9'' ”man in the picture for scale. 

2. We can see that the Railroad rests higher than Great Northern for most of the stretch of the road and MoPac is even higher in elevation. This is why the height of the wall had to be so great since it is being built solely to diffuse the noise from MoPac and not the railroad. You can see on the elevation picture (see link to pictures below) that the elevation for MoPac near Silverleaf/Greenlawn area is at 20’' , so the wall height would just reach the surface of MoPac in vertical height.

3. The criteria for establishing a sound wall was explained and a key component of the criteria was that the project would need to provide a maximum cost per benefit to receiver of $25,000. So for example, if there are 10 receivers then the cost of the project could not exceed $250,000.– This is per wall and Great Northern is divided into two walls – Foster(approx) to Far West and Far West to 2222. The issue that I confronted them with is that there are only 22 voters for the Foster to Far West wall which means the wall could only cost $550,000 for a 20'’ wall that stretches nearly ½ mile. They calculated the wall to cost $1 million (and change) but allocated 42 beneficiary receivers which brought the cost per beneficiary receiver down to $23,000. Their logic is that since the wall is 20’' high more than just those homes that line Great Northern will benefit from the noise reduction and therefore they can include those homes in their calculations (looking at their maps it appeared they went at two and sometimes three homes deep on most streets). The bottom line that I confronted them with for which they could not reply is that they are using homes to make their cost/benefit numbers work but they are not affording those same homes the right to vote as to whether they want a wall built. 

When asked if they could not extend the vote to these homes used for their calculations they said it was possible “but where do you stop”?

4. The wall is being built solely for the purpose to diffuse noise from MoPac; not the trains. Therefore materials will be selected, and it will be designed and built for that purpose alone. It was said during the meeting that the wall should soften the train noise some but they could not predict by how much or to what extent. 

5. The wall will be built 2.5' – 3’' off of Great Northern but this distance varies depending on where you are at on Great Northern. 

6. According to their calculations and forecast models the decibel level for the home at the end of Silverleaf is 63/64 without the wall. They are predicting that the wall would lower the volume 1 decibel level to 62/63 which they admitted was not a difference a human would be able to notice.  For Yellowpine, the decibel level dropped by about 4/5 decibels or the difference according to TxDOT between a vacuum cleaner at 9 feet away and people having a conversation at 3 feet away. 

7. Ballots were mailed out with a brochure for the project and a two-page letter. I have included a copy of these in the pictures. Neither the ballot nor the letter provide any details as to the height of the wall for the location where the person who is voting lives nor does it provide any information as to the current noise level for their location and the proposed difference that the wall would make, though this information is available and could have been included. Several people at the meeting were easily looking up the noise (before/after) for their streets / homes. When asked why voters were not given more information so that they could make a fully educated decision the answer was that voters were given a link to a website in the letter they received as well as a list of the community meetings they could attend.  It should be notedthat the website does not contain any reference to the height of the wall nor the impact to the noise. 

8. Because the wall is being built in the city’s right of way, the City Council will have the final vote as to whether the wall is built. I failed to clarify if the vote would be on each wall segment or as an all or nothing project. I was told by a representative from the city that a committee would make a recommendation to the council that would mirror the resultsof the vote but after that it was up to the Council as to whether they would follow that recommendation.

Link to Pictures:

Michael Nink
michaelnink [Email address: michaelnink #AT# - replace #AT# with @ ] ph: 512.656.0058