BIRD STRIKE HAZARDS AS A FACTOR IN THE SITE SELECTION PROCESS AND PLANNING FOR THE FUTURE NEW LISBON

The New Lisbon Airport site selection process was started in 1969. By 1998, 12 of the 14 original candidate sites had been rejected. The two remaining locations were Ota, NNE of Lisbon and N of the Tagus River and Rio Frio, SE of Lisbon and close to the estuaries of the Tagus and Sado Rivers (both natural reserves, one with Special Protection Zone status). NAER (Novo Aeroporto S.A., created in 1998 to conduct the new airport development process) set up a multi-criteria analysis of the 2 sites, to assess the technical, aeronautical, socio-economic, financial and environmental factors. Bird studies (carried out within the framework of the environmental studies and including fieldwork during May-October 1998) concluded that Rio Frio is close to bird migration routes and thus affected by a high level of migratory movements. An airport in Rio Frio would in all likelihood, be exposed to bird strike hazards against which no mitigation measures are, as yet, available. In another study, a mathematical model was developed to compare expected risks at the two locations. Despite its shortcomings, the model concluded that, at Rio Frio the risk would be moderate to high, whereas in Ota it would be low to moderate. The study also concluded that Rio Frio would always be affected by a high level of water bird traffic moving between the two nearby estuaries. NAER hired the third author, via ICAO, to review these reports and he concluded that, despite a lack of adequate data, the Ota location was preferable since a larger number of migratory and local flights of high risk bird species can be expected in Rio Frio. When the environmental studies concluded that the Rio Frio option was "not sustainable" from an Pessoa, Sequeira & Blokpoel 358 environmental point of view, the Portuguese Government decided to exclude it and, thus, approved the Ota location. It was subsequently also decided to carry out in-depth bird studies and NAER hired the third author, again via ICAO, to advise on the terms of reference for those studies.