Page 286 - 360.revista de Alta Velocidad - Nº 5

Grande, Zacarías. Torralbo, Julia. Lobera, José Manuel. Sánchez-Cambronero, Santos. Castillo, Enrique.

However, the complex orography, characteristic of the North of Spain, makes the construction
of a high-speed rail line difficult. In spite of the huge social benefits that a high-speed train
could mean, construction costs could be excessively high.
For this reason, there is a strong need for a new solution that offers a considerable reduction in
construction and maintenance costs without a great impact on travel times.
After conducting a demand analysis, it has been estimated a demand of approximately 1.1
million passengers in the first year travelling between these two cities.

2.1.2 High speed line proposal

All the factors discussed in the previous section make the alternate double-single track (ADST)
line the best solution for the Santander-Bilbao corridor. The features of the proposed line
include mixed traffic, Iberian-gauge track (1,668 mm) and a design speed of 250 km/h.
The layout of the line, as depicted in Figure 2, consists on an inland itinerary pursuing a straight
line. In order to reduce costs, the existing infrastructure nearby the cities of Santander and
Bilbao is used.

Figure 2. Existing railway line and initially proposed HSR line between Santander and Bilbao.

Trying to minimize the environmental impact of this infrastructure, the initial layout has been
modified to avoid (see Figure 3): (1) inappropriate land uses; (2) human settlements with more
than 100 inhabitants; (3) Site of Community Importance (SCI) in a radius of 1 km; and (4)
Protected Areas.
Hence, the ADST line proposal meets the criteria in most of this path as depicted in Figure 4
except for:

• Santander and Bilbao accesses, where the use of the current railway platform is proposed.

• In the vicinity of Bilbao, where potential environmental impacts emerge to coniferous
forests. Consequently, to mitigate its impact, tunnels in this area are suggested.

284 360.revista de alta velocidad