Compilation of Noise Programs in Areas Outside DNL 65 (2009)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

There are a number of existing and emerging reasons that airport operators need or desire to take action to address noise outside the Day–Night Average Noise Level (DNL) 65 contour, including the following: • Airports are required by court order, • Reasonable and cost-effective programs are available to address residential concerns outside DNL 65, • Airports have adopted local land use compatibility guidelines that apply to lower impact levels, • Airports have made commitments in support of airport capacity projects, • Existing noise compatibility has matured and substantial complaints exist in areas out- side the DNL 65 contour, and • Federal and international policy is moving outside DNL 65. Review of the actions leading to adoption of DNL 65 land use compatibility guideline demonstrates that it was intended to be adjusted as industry needs changed (in particular, as technology improvements resulted in quieter aircraft). In addition, adoption of the DNL 65 guideline in the 1970s and 1980s reflected a compromise between what was environmentally desirable and what was economically and technologically feasible at the time. Federal policy identifying DNL 65 as the level of cumulative aircraft noise considered “significant” can be traced to the U.S.DOT’s Aviation Noise Abatement Policy of 1976. No formal policy state- ments have been issued since 1976 that address noise outside DNL 65. For this ACRP synthesis, an online survey of airport staff was conducted regarding noise outside DNL 65. The survey was designed primarily to identify the reasons for addressing noise outside DNL 65, and the wide range of noise abatement, mitigation, and communication tech- niques used to address noise outside DNL 65 that extend beyond sound insulation. Potential survey recipients were identified by the consultant and Project Panel based on some know- ledge of noise issues at subject airports. Other airports were invited to participate through an article in the newsletter Airport Noise Report. As a result, the pool of respondents does not nec- essarily reflect average opinion on the subject of noise outside DNL 65; it does, however, rep- resent a diverse sample of airports in terms of size and geography. Of the 43 airports targeted, 35 responded for an 81% response rate, which exceeds the 80% target for ACRP synthesis stud- ies. Given the relatively small sample size, conclusions should not be considered definitive for all airports, but illustrative of the range of challenges airports face and the variety of approaches to address them. The survey included five general questions regarding noise issues outside DNL 65. The responses to these questions are instructive: • A majority of respondents (83%) indicated that noise issues outside DNL 65 were “impor- tant,” “very important,” or “critical” to their airport. The remaining 17% were evenly split, stating that noise issues outside DNL 65 were “somewhat important,” or “not at all important.” SUMMARY COMPILATION OF NOISE PROGRAMS IN AREAS OUTSIDE DNL 65

• The most frequently listed method of minimizing noise outside DNL 65 was operator edu- cation and outreach (74% of respondents), followed by noise abatement flight tracks (69%), preferential runway use programs (66%), noise abatement departure or arrival pro- cedures (60%), and ground noise control (51%). • Eighty percent of respondents indicated that “community concerns” were the motivation for addressing noise outside DNL 65; 57% also indicated that “preventive planning” was a motivation. • Almost three-quarters of respondents (74%) indicated that more than 75% of their air- port’s noise complaints come from people who live outside DNL 65. • The most common outreach tools to communicate with people exposed to noise outside DNL 65 are websites (74%), community meetings/forums (74%), online tracking (40%), and newsletters (40%). The survey also found the following: • A majority of surveyed airports use noise abatement departure (63%) and arrival (51%) flight tracks and departure (54%) and arrival cockpit procedures (40%) to minimize noise over residential and other noise-sensitive neighborhoods. However, among sur- veyed airports there is no consistency in methodology among airports for evaluating noise abatement outside DNL 65, and there is little guidance or support from the FAA on appropriate metrics or criteria for evaluating noise abatement procedures. • Most airports reported some procedures to minimize ground noise (69%); 25% of those airports reported that the procedures were developed primarily to address noise out- side DNL 65, and an additional 38% reported that procedures were developed to address noise issues both inside and outside DNL 65. • More than half of the surveyed airports (57%) reported having land use compatibility measures that apply outside DNL 65. The tools used by airports for land use compatibil- ity planning include zoning, building permits that require sound insulation of residential and noise-sensitive nonresidential land uses, and disclosure to residents. • The majority of respondents (58%) do not provide sound insulation to homeowners living outside DNL 65. However, 20% provide sound insulation for homes in contiguous neigh- borhoods (“block rounding”), and an additional 15% provide sound insulation for homes within the DNL 60 dB contour. • Nearly three-quarters of respondents (74%) reported that they use both websites and face-to-face meetings to communicate with people exposed to noise outside DNL 65. • The responding airports communicate with pilots about noise outside DNL 65 in a num- ber of ways: the most common are pilot briefings (40%) and Jeppesen inserts (40%), posters and handouts (37%), and FAA standards (17%); other methods include airfield signage, Airport Facility Directory Special Notices, videos distributed through flight schools, and phone calls. The two case studies presented in this synthesis were selected to reflect a diversity of airport size, geography, and strategies to address noise issues outside DNL 65. The case studies demon- strate that there is a need for airports to have flexibility in addressing noise outside DNL 65— whether because communities have demanded it (Naples Municipal Airport) or because the air- port has conducted proactive planning (Dallas/Ft. Worth International Airport). Both airports offer strategies that could be adopted by other airports as best practices for similar situations; the common elements include invested staff, consistent and transparent communication, and close collaboration with local land use planning organizations. This synthesis identified the need for additional research in the following areas: • “Toolkit” of strategies to address noise outside DNL 65 with recommended best prac- tices that could help airports identify those strategies best suited for a variety of noise issues outside DNL 65. 2

• Communication—Better methods are needed for working with local communities. • Evaluation of noise abatement strategies outside DNL 65, including noise metrics, cri- teria, and benefit-cost analyses. • Land use measures—This study identified a need to identify the barriers to implement- ing land use measures. • Complaints—The relationship between noise complaints and noise level is still not well understood. Areas for research in this area include: (1) an evaluation of how complaints are made, recorded, and dealt with; (2) how airport operators use and evaluate complaint levels to drive noise programs; and (3) how airport operators evaluate the effectiveness of noise programs through changes in complaints. • Case studies: Those described in this synthesis are instructive; however, the scope of this project did not allow for an in-depth analysis or discussion of some of the best prac- tice strategies that could be derived from these airports. 3