Environmental Engineering Reference
In-Depth Information
are presented, namely Ota (first choice) and Campo de Tiro de Alcochete (CTA),
the proposed location. Both locations are within the huge river Tagus Basin and in
the vicinity of the large Tagus estuary.
Methodology
Objectives and Constraints
A major constraint of the study was the time limit of 6 months and the fact that not
much field studies were developed for the locations, in particular for the new one.
The first alternative location (Ota) presented a set of preliminary studies and a lay-
out of the runways that although incipient, could support the analysis to a much
higher degree compared to the most recent proposal,
Campo de Tiro de Alcochete
(CTA). Therefore the working methodology needed to be accurate, effective and
make the most out of the existing information.
The team responsible for the analysis of the surface water resources was twice
at the location of CTA, collecting information and doing field work, and once at the
location of Ota. These visits and the experience of the working team were important
assets for the development of the study. Part of the LNEC team was involved in the
preliminary studies of the Ota location, providing terms of reference for water
resources studies.
An infrastructure with the complexity of a new major national airport concerns
also the construction of new transportation structures, and changes the urban devel-
opment in its vicinity. Neither of these aspects was analysed. The study was focused
on surface water resources of the areas directly affected by the impermeabilization
due to the construction on the airport platform.
Selection of Characterization Indicators
In order to support the analysis, a set of characterization indicators have been estab-
lished. Their purpose was to describe in an objective manner the characteristics and
conditions of the surface water, or other factors that may affect it. The following
characterization indicators have been assigned to the study:
1. Percentage of catchment impermeabilization
2. Length of rivers that are affected
3. Floods
4. Soil erosion factors
5. Pollution sources
6. Water quality and uses
7. Local availability of water for the airport uses
