There is a long-standing debate in Belgium over the choice of flight routes around the national airport located northeast of the capital, Brussels. A plan last year that reorganized departure routes, routing the majority over densely populate areas of the capital, was met with strong protest from Brussels residents who now had to endure noise nuisance they didn’t have under the previous routes. Noise nuisance from airplanes is, according to recent studies, linked to an important increased risk (10-20% higher likelihood) of stroke, coronary heart disease, cardiovascular diseases, and death. Assuming 1) that there is an unavoidable amount of flights above populated areas and 2) that it is impossible to fully deaden the noises thereby engendered, what would constitute a just distribution of flight routes? In other words, what is a just distribution of suffering and risks caused by plane nuisance? In this post we present three possible answers and defend one of them.
 
 
 
 
1.      Fair distribution of costs and benefits through the market
 
One answer to the question is to say that the market already fairly allocates the benefits and burdens associated with living under established flight routes. Rents and property prices reflect the distribution of preferences that people have when it comes to the trade-off between noise pollution and money. This approach would favour policies that maintain the status quo and reject introducing any changes in flight routes given that choices were made and expectations were built around a stability of flight routes. We see two problems with this approach. Firstly, we do not think that the choices made by some individuals to live under the flight routes are genuine choices that reflect their preferences. On the one hand, information about the health costs of airplane nuisance was not available till recently (2013). On the other hand, there is the worry that many individuals have no option but to take up residence under flight routes thereby sacrificing or risking their health not because of a preference for money but because properties in those areas are the only ones they can afford. Secondly, even if we were to be certain that choices of all individuals were genuine or to disregardvoluntariness, a problem remains with regards to the consequences those choices have on third parties, in this case the children of those who opt for health risks in exchange for cheaper rent.
 
2.      Minimization of total suffering
 
A second answer says a just distribution is one that minimizes total suffering. The argument that flight routes should be organized such that airplane nuisance affects the least number of people is popular and intuitive. It favours policies that concentrate flights over the least populated areas. This approach relies on utilitarian reasoning, and although electorally attractive, it suffers from the classical objection to utilitarianism: it sacrifices the welfare of part of the population for the aggregate welfare.
 
One could argue, however, that offering compensation to the victims (those who live under the flight routes) can address this objection. By compensating the victims we show concern for their suffering and balance out the loss in wellbeing incurred by the noise pollution. The compensation can take the form of an offer for relocation or monetary compensation. Yet, we think this response suffers from the same problems as the first answer which relies on compensation through the market. The worry is that some might opt for monetary compensation and hence nuisance and health risks because they are economically disadvantaged and that their choice at any rate unfairly impacts their children. We recognize that forced relocations could be one way to counter this worry. Nevertheless, we think it is problematic as it imposes the burdens of relocation on only part of the population making it open once more to the initial objection of sacrificing the welfare of some for the aggregate welfare.
 
3.      Equalizing suffering and risk
 
The answer we favour to the question of just distribution of nuisance and health risks is one that advocates an equal sharing of the burden because it considers it unjust to ask some to endure suffering or risk their health for the aggregate welfare. The policy favoured by this approach would be maximal dispersion of flights. Of course, maximal dispersion is only a proxy for equal distribution of burdens for there will be inevitable inequalities. Equalizing risk is impossible; those living close to the airport will be more affected than those living farther. Maximal dispersion can be complemented by forced relocation (for those areas where the risk is highest) and compensation (although the same concerns about compensation above apply)The principle of equalizing suffering and risk might strike many as counterintuitive. Don’t we by maximal dispoersion simply subject a higher number of people to nuisance and risk than would have been the case under concentration policies? We stand by this principle, however, because we think it is the only one that treats everyone as equal and expresses equal concern/respect to each. Unlike the utilitarian argument, it can be justifiable to each individual. And, we think that justifiability to all trumps efficiency considerations. 

That said, we note that a utilitarian appraoch might also support a policy of dispersion if we take into consideration the following two reasons. First, the negative impact of noise pollution is non-linear (the nuisance of two planes is higher than twice the nuisance of one). This means that concentration does not necessarily minimize aggregate suffering. Second, a policy of maximal dispersion might be highly effective in making a substantial number of citizens aware of the nuisance and dangers of airplane noise which could ultimately lead to more effective lobbying to reduce air traddic and find radical alternative solutions.
 
 
Siba Harb and Pierre Etienne Vandamme