December 25, 2001
Honorable Rick Santorum
United States Senate
Washington, DC 20510-3804
Re: Route 202 Section 300 Expansion Noise Abatement
Dear Senator Santorum,
Thank you for forwarding Mr. Andrew L. Warren’s letter of November 20, 2001 concerning noise mitigation and pavement design for Route 202, Section 300 Improvement Project.
The meetings with PennDOT sponsored by Representative Rubley and Senator Thompson with PennDOT at the request of the Great Valley Association did much to bring the issue of noise abatement to the attention of our community and we are very grateful for their support.
There are several comments made by PennDOT in response to our letter of October 31, 2001, which require clarification. For instance PennDOT admits that "there may be up to a 3 decibel difference" in noise "between asphalt paving and concrete pavements" but they go on to say "that it is incorrect to state that asphalt at a minimum is 3 decibels quieter than concrete". However, the National Academy of Science’s publication NCHRP Synthesis 268* states " In general, when dense-graded asphalt and pcc (Portland cement concrete) pavements are compared, the dense-graded is quieter by 2-3 decibels and even more benefit is shown if the dense-graded is compared to transversely tined pcc pavements. Open graded asphalt shows the greatest potential for noise reduction. In this instance the reduction when compared to dense-graded asphalt ranged from 1-9 decibels". Therefore, PennDOT's statement of "up to 3 decibels difference " should have read up to 9 decibels difference, depending upon the type of asphalt pavement used. As you can see our estimate relative to noise reduction was decidedly on the conservative side.
PennDOT also disputes our claim that a 3-decibel difference represents a 41% increase in noise pollution. They claim, " that in reality because the loudness of sounds varies from person to person, and that for most people it takes at least a 10 decibel increase to double the loudness of sound. However " Ten decibels doubles the intensity of the sound, but 3 decibels, per NCHRP, corresponds to doubling the distance from the noise, reducing the traffic volume by 50% and reducing the speed by 25%. In effect a 3-decibel reduction has the effect of taking 100,000 cars and trucks in average daily traffic (ADT) and reducing it to the noise level of 50 ADT. In other words a person living 100ft from Rt.202 would hear the noise as if his home was 200 feet from Rt.202. This reduction in noise can have a significant and positive impact upon the quality of life for residents living along Rt. 202.
In respect to cost PennDOT acknowledges that the cost of installation favors asphalt but that "over the long term, concrete is a much more durable material with a significantly longer life span". This suggests that asphalt is more expensive over the long term, which we strongly dispute. It is important to note that this conclusion is based upon PennDOT’s present system of comparing the life of ALL asphalt pavements, that is 1-inch overlays on concrete as well as full depth asphalt pavements, to the life of only full depth pcc pavements. This distorts the life cycle of full depth asphalt in favor of pcc pavements. A more accurate comparison would be full depth asphalt to full depth pcc pavements. For example the Blue Route (I-476) is a full depth asphalt road and has been operating for 10 years and performing very well. Yet based upon the mix of overlay and full depth data kept for asphalt pavements PennDOT’s life cycle data suggests that this route is due to be overlaid. The Blue Route is a properly designed full depth-asphalt pavement not an average overlay of asphalt on concrete, which distorts the comparison between these two pavements. . Why should there be a discrepancy in the data measuring service life of full depth asphalt versus full depth pcc?
Pavements similar to the Blue Route can be found in states adjacent to Pennsylvania e.g. I-95 in Delaware and Maryland. Another is The New Jersey Turnpike, which just received an award for 50 years of service without having to be reconstructed. An Ohio study of asphalt and pcc pavements, of similar age and traffic volume, noted that asphalt pavements had lower installation costs and had never been reconstructed despite having an age range of 27 – 35 years. This gave asphalt an increasing advantage over pcc as these pavements aged.
PennDOT alludes to the fact that they "have learned about the means for creating quieter surface textures. Therefore, regardless of which pavement type evolves from our design, please assure your constituents that its deployment on Route 202 should not pose a noise concern". The current thinking in respect to pcc pavements is to do what is known as random transverse tining. I-275 in Michigan was a pcc pavement with random tining. The citizens living near this newly constructed road complained to the Michigan DOT about the noise and ultimately the pavement had to be diamond ground. Diamond grinding is an expensive operation, which adds to the cost of installation of pcc pavements and still doesn’t produce a road as quite as a full depth asphalt road. We understand that Section 400 had to be diamond ground. We are not impressed with the quietness of this stretch of Route 202 diamond grinding notwithstanding.
Would that it was otherwise but we are not reassured that concrete is the best option, which the PennDOT letter seems to imply. On the contrary we are greatly disturbed by the noise emanating from the present concrete paved Route 202. The noise is intolerable and the expansion, which we have supported with proper noise abatement, offers to further undermine the quality of life for the residents who live along the Route 202 Section 300 corridor. We want the quietest road possible not the second quietest especially when the economics favor our position.
We want sound walls constructed from the end of Section 400 at the intersection of Swedesford Road and Route 202 along the north side of this highway out to the Great Valley Corporate Center on Route 29. We believe that these are reasonable requests. We look forward to your support to protect the quality of life for the residents who live along this highway the expansion of which is 80% federally funded.
Yours truly,
Joseph F. Maxwell
President
Great Valley Association
* NCHRP – National Cooperative Highway Research Program’s Synthesis 268, Relationship Between Pavement Surface Texture and Highway Traffic Noise.
CC Mark Schweiker, Governor
Andrew L. Warren, District 6-0 Administrator, PennDOT
Bradley Mallory, Secretary of Transportation, PennDOT
Michael M. Ryan P.E., Deputy Secretary for Highway Administration, PennDOT
Arlen Specter, U.S. Senator
Curt Weldon, U.S. Representative
Robert J. Thompson, State Senator
Roger Madigan, State Senator
Carole Rubley, State Representative
Richard Geist, State Representative
Robert J. Flick, State Representative
Karen Martynick, Chairman, Chester County Board of Commissioners
Colin A. Hanna, Chester County Board of Commissioners
Andrew E. Dinniman, Chester County Board of Commissioners
John J. Coscia, Executive Director, DVRPC