North West Rail Link Sydney

Sydney, Australia

The design and construction contract for the North West Rail Link project in Sydney involved the delivery of one of Australia's most significant metropolitan rail expansions. The project included the construction of two twin tunnels, each 15.5 km long with an internal diameter of 6.17 m, running between the existing Epping station and the new Bella Vista station. In addition, five underground stations were built—Cherrybrook, Castle Hill, Showground, Norwest, and Bella Vista—each with approximate dimensions of 180 m in length and 20 m in width.

High Speed – Sector 2

Guipúzcoa, Spain

The High-Speed Rail Sector 2 project forms part of the Basque Country High-Speed Rail Network and includes more than 11 km of tunnels and underground galleries along the route between Mondragón and Bergara.

CSST – Combined Sewage Storage Tunnel

Ottawa, Canada

The Combined Sewage Storage Tunnel (CSST) is a key component of the Ottawa River Action Plan, developed to improve river water quality by reducing wastewater discharges during periods of intense rainfall. The project consists of two underground tunnels designed to operate both as wastewater collectors during normal conditions and as stormwater storage tunnels during peak flow events, helping prevent direct discharges into the river.

Barcelona Metro - Lines 9 and 10

Barcelona, Spain

The Barcelona Metro Lines 9 and 10 project is one of Europe's most innovative urban railway developments, based on the Continuous Station Concept, which integrates stations and tunnels within a single large-diameter structure. DRAGADOS has participated in the construction of several sections of the Lines 9 and 10, a landmark project that incorporates the Continuous Station Concept. The company has delivered three separate contracts covering the sections Gorg – Sagrera Shaft, Sagrera Shaft – Habaneras Extraction Shaft, and Zona Franca – Mandri Station, the latter currently under construction.

Crossrail C-305

London, United Kingdom

The Crossrail C305 project was the largest contract awarded within the Crossrail Project and one of the largest infrastructure contracts in Europe at the time. The works involved the construction of twin tunnels lined with precast, fibre-reinforced reinforced concrete segments, using four Earth Pressure Balance (EPB) tunnel boring machines. Excavation was carried out mainly through London Clay formations.

Madrid Metro Extension

Madrid, Spain

Line 11: Plaza Elíptica – Conde de Casal The Madrid Metro Extension Programme represents one of the largest underground transport developments undertaken in Europe, delivering more than 165 km of new lines and 168 stations between 1995 and 2011. DRAGADOS is currently delivering the extension of Line 11 of the Madrid Metro, along the section between Plaza Elíptica and Conde de Casal. The contract includes the construction of 7 km of single-bore, double-track tunnel, with an excavation diameter of 9.38 m, executed mainly using an EPB tunnel boring machine, launched and operated from Comillas station towards Conde de Casal. The project also comprises the construction of five new stations —Comillas, Madrid Río, Palos de la Frontera, Atocha and Conde de Casal— together with seven emergency exits, six ventilation shafts, and five pumping shafts, integrated into different structures along the alignment.

SR-99 Alaskan Way replacement

Seattle, USA

The SR 99 Alaskan Way Replacement project involved the construction of a 2,688 m urban road tunnel beneath downtown Seattle using the world's largest EPB tunnel boring machine at the time of construction.