Airplane Noise Pollution
In the warmer months, the #1 issue my office hears about is airplane noise. While the residents of Southwest Minneapolis love having easy access to the airport, the takeoffs and landings have not always been fairly distributed over the Twin Cities metro area, leaving many of the most populated areas—urban neighborhoods—to bear much of the burden.
The best way for me to keep you informed about what we're working on is through our periodic airplane noise newsletter. To subscribe, send an email to Kendal Killian, my Senior Policy Aide (firstname.lastname@example.org), with the subject line "Airplane Noise Newsletter."
Here are some of the previous updates we've sent out via this newsletter:
See the Metropolitan Airports Commission (MAC)’s website for more resources:
To file a complaint about airplane noise, please visit: https://www.macnoise.com/our-neighbors/file-noise-complaint. (We recommend filing complaints during unusually noisy times; the data is very helpful for the City of Minneapolis.)
To contact your MAC representatives, please visit: https://www.metroairports.org/Airport-Authority/Metropolitan-Airports-Commission/Governing-Body.aspx.
For a schedule of MAC public meetings, please visit: https://www.metroairports.org/Airport-Authority/Metropolitan-Airports-Commission/Public-Meetings/Public-Meetings.aspx. (Note: not all meetings allow public comment.)
To access FlightTracker, the MAC’s map-based research tool, please visit: https://www.macnoise.com/tools-reports/flighttracker.
Airport-noise mitigation for seven blocks in Ward 13
A number of Ward 13 homes, which are in the path of arriving airplanes, will be eligible for airport-noise mitigation through the Metropolitan Airports Commission (MAC) in 2017. Minneapolis–and other cities affected by airport noise—entered into an agreement in 2013 with MAC to provide mitigation to homes if noise stayed above a designated level for three consecutive years. Due to the release of new noise maps, homes are becoming eligible for mitigation under this program for the first time. MAC has an interactive map where you can type in your address to see if you are included.
Before I continue in more detail, I want to assure you that the agreement with MAC—which has been in effect since 2013—does not mean that the City is acquiescing to noise. Mitigation is a tool to reduce the negative impacts of noise, but it is far from a solution to noise concerns. I—along with my colleagues at the City—continue to pursue all possible avenues for noise relief. While I will encourage residents to take advantage of noise mitigation packages, our first priorities at the City remain noise prevention and noise reduction.
This year, homes are becoming eligible for the package known as the “Partial Mitigation Package.” What is included in that package, however, depends on whether or not the home has been mitigated by MAC in the past. Most of the 137 single-family homes becoming eligible have already been mitigated to some extent in the past under a different program; only 18 are eligible for the first time. Essentially, the value of prior investments by MAC is deducted from the value of the overall package. Homes that have not had mitigation before will get more resources than those that have. You can read more about the mitigation packages here. [Note: There is information on that page about a “Full Five-decibel Reduction Package”; no homes will be eligible for this package in 2017.]
Note: If you use the interactive map and it says your home is in "year 1 of 3” or “year 2 of 3,” then you are NOT eligible for mitigation. However, you could be eligible if current noise levels continue for 3 consecutive years. As mentioned above, however, the City advocates for actual noise reduction over mitigation, so there’s a possibility that noise could be reduced. In that case, a home in year 1 or 2 of eligibility would not reach three years of consecutive noise and would not be eligible for mitigation.
Why has noise increased in this area?
The area that is experiencing a noise increase, when measured by the noise model, is along a path used by airplanes arriving to the airport over Minneapolis. Nighttime flights are largely responsible for these seven blocks becoming eligible. The noise formula used for measurement treats nighttime flights (between 10 pm and 7 am) as if they are 10 decibels (dB) louder than they actually are, recognizing that these flights are particularly disruptive to residents’ lives. There has been some increase in nighttime flights and those flights have a big impact on the daily averages created by the model.
How is the noise measured?
Every year since 2007, MAC has produced an “Annual Noise Contour Analysis” which shows the noise exposure for the previous year. These maps are produced using the Integrated Noise Model (INM). The model takes data from the actual flights at MSP to determine what kind of plane was flown and where it went, and then it plugs in assumptions about how much noise that plane makes based on data from field tests. INM penalizes nighttime flights by treating them as if they were 10 dB louder than they actually were. These numbers then are averaged over a 24-hour period. The numbers produced by this model have the label of “DNL” (Day Night Average Sound Level). So, while the numbers are roughly equivalent to decibels, they aren’t exactly the same. The annual map draws a line (contour) around areas based on their noise level. All the homes eligible for mitigation in 2017 are included because they are inside of the 60-62 DNL noise contour.
Our agreement with MAC for mitigation requires the use of INM, which has been the FAA (Federal Aviation Administration)-approved noise measuring tool since the 1970s. I—and the City—have expressed dissatisfaction with INM modeling and DNL as a measure of noise. By averaging all the noise over the day, some of the impacts get lost. Many complaints I hear from residents relate to the frequency of operations, with one plane coming right after another. That experience is simply not accounted for with this noise model. Additionally, since the INM measures the average, it’s possible to get the same average noise on a block that hears 10 planes and a block that hears 50 planes. Due to these issues, the City consistently advocates at a federal level for new ways to measure noise impacts. Due in part to engagement from Minneapolis, our partner cities and advocate groups, the FAA is actually exploring this issue, acknowledging that frequency of noise is a concern not captured using the current model. These efforts are encouraging, but slow. In the meantime, INM modeling is being replaced by AEDT (Aviation Environmental Design Tool). However, AEDT has the same basic characteristics as INM when it comes to measuring noise but it adds information related to emissions.
If you want more detail about the agreement for mitigation, how noise is measured, or noise data from 2015, check out the Annual Noise Contour Analysis for 2015.
No action needed at this time
Once again, property owners who are eligible for mitigation will be contacted by MAC by July 1. There is no action to take until you have received that letter. MAC has promised me that the letter will include information for a single contact person to help answer questions that arise in this process. I appreciate that. City staff and my office have been working with MAC to ensure this process goes as smoothly as possible. Mitigation is never a solution to airport noise, but it is a measurable step as we continue to fight for more equitable distribution of airplane noise pollution.
For specific questions about this program, more information will follow from MAC. In the meantime, do not hesitate to contact my office.
Yours in service,
Looking for more information?
The City’s website on airport noise
Previous 13th ward airplane noise newsletters:
MAC’s website on noise mitigation:
On Friday, July 24, the Federal Aviation Administration temporarily suspended certain operations on Runway 30-Left and Runway 35 at Minneapolis-St. Paul International airport.
A non-intersecting converging runway operation occurs when the flight paths of two aircraft intersect but the runways themselves do not. This “intersection” in the sky poses potential risks if a landing aircraft must discontinue its approach and go around. This action could bring the airplane too close to an aircraft departing from the other runway, risking a mid-air collision.
Based on a National Transportation Safety Board (NTSB) recommendation issued on July 1, 2013 regarding converging runway operations, the Federal Aviation Administration (FAA) required air traffic control at airports with this configuration to modify arrival and departure procedures. The new requirements for converging runway operations stem from FAA analysis of aircraft go-around events between 2011 and 2013 that showed reduced safety margins between some arriving and departing aircraft.
The FAA used a phased-in approach nationally, which began in January 2014, to introduce these safety requirements at airports identified by the NTSB. Some of the airports that have changed their operations include Baltimore, Boston, Charlotte, Chicago O’Hare, Dallas-Ft. Worth, Denver, Houston Intercontinental, Las Vegas, Memphis, New York JFK, Philadelphia, Salt Lake City, Tampa and Washington Dulles. Prior to the phasing in of the safety requirements outlined by the NTSB, FAA personnel at Minneapolis had completed a Safety Risk Management Document that appeared to address the risks associated with converging runway operations, specifically landing Runway 35 and departing Runway 30L. In late July 2015, we determined that the mitigations in the Safety Risk Management Document were not sufficient to meet the standards of the Converging Runway requirement and the procedure was terminated. There was no event that occurred that caused this termination.
Minneapolis – St. Paul International Airport (MSP)
The immediate solution for MSP (while in a Northwest Flow Configuration) was to prohibit landings on Runway 35 when departures are occurring on Runway 30L. The airport is in a northwest flow approximately 60 percent of the time. This restriction results in an arrival rate reduction of up to 30 percent when in this configuration.
The FAA will continue to focus on increasing the arrival and departure rates while adhering to the new safety requirements.
I’m writing to alert you to some news, and to potential for changes in aircraft patterns around MSP airport. Today we learned that the FAA has suspended a certain operating procedure that was used at MSP, and that the suspension could result in some changes in how the runways and airspace are used. Specifically, Runway 35 can no longer accept arriving airplanes when Runway 30L is being used for departing aircraft over Minneapolis. You don’t need to be familiar with the runways numbers to understand the issue. Essentially, the two runways intersect, and the FAA has been carefully managing the aircraft on each runway to make sure that arriving airplanes and departing planes do not collide. The big concern is not about planes crossing on the ground; the concern is about the potential for conflict in the air if the arriving airplane needs to abort its landing and do a go-around. The NTSB has indicated that they aren’t entirely satisfied with measures in place to avoid a collision when conditions like this exist (at any airport). The FAA has stated that the procedure is “temporarily suspended” – we don’t know what that means right now, but it does not sound like they will be using this procedure again anytime soon.
It’s too soon to understand the implications of the suspension, but this change significantly reduces the amount of arriving airplanes that the airport can accept. The suspension means that MSP can now accept about 60 planes per hour instead of the potential for 90. A reduction in flights might sound like a great thing, but the FAA says they are looking for alternative ways to accommodate the current capacity of the airport. They are looking at alternate configurations which could result in big changes in how runways are used, air traffic patterns, and the areas that are exposed to noise. There are more questions than answers today, but as I learn more I’ll keep you posted.
Again, this is news we just learned today and it’s very early to speculate about the implications. I wanted to let you know that you may notice some changes in the air traffic patterns you are accustomed to. This is the beginning of a conversation with you, the FAA, and the Metropolitan Airports Commission (MAC) about what this means and how it affects our community in the short and long term. The airport is in the process of updating their Long Term Comprehensive Plan and this is an issue that will need to be examined and addressed before that process can continue.
Yours in service,
Thank you, neighbors, for your particular care and attention to airport noise and its effect on our community. My goal in sending out this periodic newsletter is to keep people who expressed interest in the topic of airports highly informed of the noise mitigation and other efforts underway as a result of collaboration between the city, the Metropolitan Airports Commission, and the Federal Aviation Administration. We try to make a lot of dense, technical information easily consumable (and we welcome your feedback).
It is because of your continued efforts that we can and will make progress together.
What will MSP Airport look like in 2035? Planning Process Underway
Every five years, the Metropolitan Airports Commission (MAC) updates their Long-Term Comprehensive Plan (LTCP) for the airport. Each plan looks ahead 20 years and identifies what MAC expects to happen at the airport, such as the number of passengers and planes. The plan assesses facility needs and environmental considerations, and looks at alternatives to meeting the future needs and challenges of the airport. MAC is currently working on the 2035 LTCP.
One of the first steps in the process is forecasting; the airport is expected to grow in terms of the number of people moved, and the number of airplanes. The graphic below shows a forecast of the number of airport operations. An “operation” means either a departure or an arrival. The baseline forecast, shown as a blue line, is 511,000 annual operations in 2035. The forecast also includes a range of possibilities – with 621,000 operations per year at the high end and 400,000 operations at the low end.
To help put this information in context, the number of operations in 2014 was 411,760 and the number of operations in 2013 was 431,573. The year Minneapolis - St. Paul International Airport (MSP) experienced its highest level of operations was 2004 and the total was 540,727. You can see this historical data in the graph. For the last LTCP, the forecasts produced in 2009 showed a baseline forecast of 630,837 operations in 2030. The current baseline forecast is quite a bit lower than that and a big reason is that airlines are using larger planes and can move more people with fewer planes.
When it comes to the number of passengers, MAC forecasts 25 million enplanements in 2035. An “enplanement” is a person boarding a plane, whether the trip originates at MSP or if it’s a connecting flight. The number does not count the act of disembarking or “deplaning.” In 2014, there were about 17 million enplanements at MSP.
The next step in the LTCP process includes evaluating environmental considerations and looking at alternative ways to meet the future needs of the airport. The alternatives being looked at relate to where to locate airlines and where to add more gates (Terminal 1 or Terminal 2). When that work is done, MAC will present the plan to the public for input. Minneapolis has requested that their outreach include a meeting for residents to be held in Minneapolis at a time and place that is accessible. We will keep you posted on further information about the plan and opportunities to share input (likely in June or July). If you want to see more on this topic, you can watch this presentation that MAC staff gave to a MAC committee.
New Arrival Procedures Now in Use
There continues to be questions regarding RNAV (Area Navigation) procedures and whether or not they are being used at MSP. As you may recall, RNAV was a source of controversy in 2012. That controversy was specifically about using RNAV for departures and the potential to consolidate airplane tracks, thus creating “highways in the sky.” Thanks to the advocacy of residents, the City, and other partners, RNAV for departures was halted and the Federal Aviation Administration (FAA) has not pursued it since then. RNAV procedures for arriving airplanes, however, moved ahead and are now in use. RNAV for arriving planes did not present the same concerns as departures because planes arriving over Minneapolis are already in a straight line formation in order to line up with the runways. For some, there may be benefits with RNAV arrivals because they can use a different kind of descent (Optimized Profile Descent) that is more smooth and gradual than stepping down as they did (the FAA says that this benefit is probably more noticeable further away from the airport, however, so we don’t know if Minneapolis residents will notice it). The arrival procedures have been in use since March 24 but they are not used by all airplanes; some planes do not have the equipment to fly RNAV procedures. Over time, the number or arrivals using the procedures will grow.
We were wise to halt the departure procedures, and we’ve sent a strong message to the FAA that they will have a high bar to meet if they come back with RNAV for departures. Other cities have not been so lucky. A “CBS This Morning” story aired in late January about the implementation of NextGen and how it’s causing noise problems in Phoenix.
MAC’s Annual Report to the Legislature
The Metropolitan Airports Commission (MAC) is required to prepare an Annual Report to the Legislature that describes recent MSP activity, current and anticipated capacity and delay for its airfield and terminals, and technological developments that could improve airport efficiency. The 2014 report is now available. The requirement is the result of 1996 Legislation when the DualTrack study was terminated. That study was looking at whether to expand MSP at its current site or to re-locate the airport. When the Legislature and Governor Carlson terminated further study of a new airport in 1996, the Legislature required this annual report and also directed MAC to create the MSP 2010 Long Term Comprehensive Plan (LTCP). That plan would look at future forecasts for the airport and explain how the airport was going to react to those needs. Minneapolis advocated for the LTCP to be updated on an ongoing basis. MAC is currently working on an update, the 2035 LTCP (see above for more details).
Changes to Runway Use
I’ve been in an ongoing dialogue with the MAC and FAA about some issues with airport operations that are of concern to me. For one, the airport operates in a north / northwest flow more than it should, and when it does, the departure runway most impactful on the 13th Ward gets used quite a bit. I’m also concerned about noise early in the morning or late at night – the noise that is particularly disruptive to sleep. I think many of these factors culminated in an increase in complaints about airport noise last summer. After much internal discussion and intense lobbying of the MAC from constituents like you, the FAA control tower is making some changes to try to improve things for Minneapolis residents. Now we will see if the changes are helpful.
During times of high capacity, the tower prefers a northwest flow (with departures over Minneapolis and arrivals over Eagan and Mendota Heights) because it allows them to land more airplanes. Therefore, this configuration is used during the busy daytime hours unless the wind or weather dictates a southeast flow. What the tower has committed to do is to try to use alternative configurations longer at the shoulder hours – the times when the airport is transitioning between higher and lower demand in the morning and at night. Rather than using a southwest flow (which means Minneapolis would still get arrivals), the FAA is proposing a “mixed flow” that puts arriving airplanes over the Minnesota River and Mendota Heights and departures over Eagan. In this configuration, neither departures nor arrivals are going over Minneapolis. This should reduce noise at least during these shoulder periods.
What does this mean in terms of real life experience? It should mean less noise in the early morning. Instead of starting departures over Minneapolis around 6:45 a.m., they will start closer to 7:20 a.m. While this change may seem small, I think this could make a difference for folks. The control tower is exploring how to implement a mixed flow in the evening shoulder period also, but we don’t know what they can do yet. Right now, there is high demand around 10:00 p.m. as planes head west.
The MAC has committed to monitoring this issue of runway use closely; they have requested to receive regular reports to committee. Again, I think these changes could make a difference and I look forward to seeing what can be done at nighttime hours. I am still concerned about the preference for a north flow during high demand periods at the airport (which is virtually all day) and the potential to use certain runways more than others giving some communities an unfair share of the overall burden. I’m going to keep working with the MAC and FAA to monitor the overall conditions this summer, and the impact of these changes.
Meeting with MSP FairSkies and Further Research into Measuring Effects of Aircraft Noise
In April, the Airport Working Group of the City of Minneapolis (an internal group comprised of council members, Mayor’s Office and departmental staff) met with representatives of local airport noise advocacy group MSP FairSkies to review the results of their analysis of FAA data on airplane noise at 35 airports around the country. In 1981, the FAA established Day-Night Average Sound Level (DNL) of 65 decibels as the guideline at which federal funding is available for soundproofing or other noise mitigation. MSP FairSkies, working in partnership with a group of University of Minnesota graduate students, looked at the impact of aircraft noise using the international standard of 55 dB DNL versus the FAA standard of 65 dB DNL (and 60 dB in Minneapolis). We appreciate the effort it took to analyze the data and look forward to continued conversations on this topic.
A few days ago, the FAA issued a press release stating that “the U.S. Department of Transportation’s Federal Aviation Administration (FAA) will soon begin work on the next step in a multi-year effort to update the scientific evidence on the relationship between aircraft noise exposure and its effects on communities around airports.” The study will include a survey to gather “public perceptions of aviation noise throughout the course of a year” although the FAA will not disclose which communities around the country will be surveyed.
Last updated Aug 23, 2017