Questions for which we seek answers
When will we have the noise study interpreted so we can understand the impact of noise (which this study suggests is not sufficient for a wall?) on the neighborhoods? New noise study to be presented January 13 at 5:30 pm at the Ward III office. All invited to attend.
NOISE STUDY QUESTIONS AND COMMENTS FROM STEVE KOZACHIK
From: "Steve Kozachik" <Steve.Kozachik@tucsonaz.gov>
Date: January 18, 2016 at 3:50:04 PM MST
To: <email@example.com>, "Beth Abramovitz" <Beth.Abramovitz@tucsonaz.gov>
Cc: "Alison Miller" <Alison.Miller@tucsonaz.gov>, "Amy Stabler" <Amy.Stabler@tucsonaz.gov>
Subject: Grant noise study
I attended the Grant noise study explanation last week - could use some clarifying information. I'm cc'ing Bob Schlanger into this. He was also there and he & I may have come away with some different understandings.
What I understand is that the RTA has adopted FWHA guidelines as they relate to noise - a way of having objective data from which to make design decisions that will be funded by the project. Two main options were discussed with respect to noise mitigation; a wall, and/or rubberized asphalt.
To qualify for project funding for a wall, the post-project noise would have to exceed 66db, or have increased by at least 15db from the pre-project levels. The wall would have to be at least 10' in height, and the noise would have to affect at least 2 properties adjacent to the roadway - and the cost of the wall could be no greater than $35K per home.
Rubberized asphalt can be used throughout the noise study area if projected levels exceed 63db (a "3db credit.")
first - are those criteria correct? I tried to take good notes. Assuming they are:
...none of the phase 2 segments appear to qualify for a noise wall based on either the 66db levels, or the increase in 15db pre:post. But the entire phase 2 segment does qualify for rubberized asphalt.
Correct so far?
What's concerning to me is that the projected - eventual - noise levels are formulated based on a computerized modeling exercise. And from what was presented, the levels are within 1-2 db of qualifying for the wall on the basis of the 'must exceed 66db' criterion. One or two db's is a pretty close call, and when it comes to long term impacts on quality of life and/or property values, I wonder if there's a plan for following up with real time data to confirm the validity of the model. This phase will be one of the first to be completed. When we all agreed to do the project in segments, one of the reasons given was so we could learn as we go. Doing post construction noise measures would seem to fall within that intent.
Given that we're the lead agency, I'm of course sensitive to the budget. And yet, if we're using certain metrics to guide design elements, they should be used under real life conditions, not based on a model that cannot predict with the accuracy we owe to the residents noise levels within 1-2 db on a post construction basis.
Will we be doing these same studies for each of the upcoming segments? Will they be used on Broadway?
Finally, based on the questions I heard last week, it might be wise to get the design team together and share with the residents the exact buffering/landscape amenities that are being considered. It sounded as though the plan may be to leave large areas of land undeveloped and hope for the best. I know that message won't be well received on the segments east of Campbell, nor will they be on Broadway.
thoughts?/ thanks - SteveK