Santo Domingo Goes Underground
Dominican Republic’s Capital Embarks on Ambitious Transit Network

To assist with construction of underground portions of the Line 1, constructors used a Dosco MK3A roadheader.

As the capital of the Dominican Republic, Santo Domingo is the economic center of the country. The city itself, founded in 1496, is home to more than 2 million of the country’s 10 million people.

In an effort to improve transportation in the city and enhance its economic viability, the government has undertaken an ambitious program to build a rapid transit network in the city.

The Santo Domingo Metro is part of a “National Master Plan” to improve transportation in the city as well as the rest of the Dominican Republic.

The project is being led by Oficina para la Reorganizacion del Transporte (OPRET), the Dominican government authority responsible for the reorganization of Santo Domingo’s public transport network. The network, which began construction in 2005, is expected to eventually achieve ridership of 200,000 passengers a day.

The project consists of several phased lines, the first of which has been completed and opened for service. Line 1 is 10 miles long with 15 stations built both underground and on the surface at an estimated cost of $700 million. It runs north-south through the city from Villa Mella to La Feria, including a station to serve Santo Domingo’s university. Originally planned as an entirely underground line, the final alignment consists of a mixture of underground, at grade and over grade sections. The first line was planned to relieve traffic congestion in the Maximo Gomez and Hermanas Mirabal Avenue areas of the city.

To assist with construction of underground portions of the Line 1, constructors used a Dosco MK3A roadheader. The 104-tonne Dosco roadheader was chosen because of its high speed cutting capability in the generally soft to medium strata to be encountered in the tunnel project. The MK3A also had the advantage of using its 270-kW boom to excavate the harder ground found on certain sections of the Metro drives.

The versatility of the machine also enabled its use at intersections where the tunnel needed to be more than double the running tunnel width. Advance rates of 1 m per hour were the general rule and up to 20 m in a 12 hour shift were achieved in completing the north to south line. The roadheader, installed in 2006, successfully completed several drives of varying distances between stations in the Line 1 section of the project, which required running tunnels 6.25 m high by 8.25 m wide.

Because of the success of the roadheader on Line 1, a second Dosco MK3A roadheader was delivered to the Santa Domingo and has started operations in this historic project. The second machine, together with the refurbished first machine, will drive various sections within the second phase of the metro system.

Line 2 will run east-west and cross Line 1 at the J.K. Kennedy Avenue. According to reports, Line 2 will span 13.5 miles and be entirely constructed underground at an estimated cost of $1.5 billion.

The Santo Domingo Metro is just the second underground rail service in the Caribbean after San Juan, Puerto Rico.

The MK3A roadheader is part of the Dosco range of civil tunneling roadheaders, which includes the 100-tonne MK4 and 120-tonne MK5 civil machines.

The 100-tonne Mk4 machine supersedes the MK3 and MK3A range and offers the latest technology for rapid and efficient excavation for all kinds of underground mechanized mining and tunneling methods in strata up to 120 MPa. Boom powers of up to 300 kW are available for this machine.

The 120-tonne MK5 roadheader is the civil tunneling and evaporate mining application version of the MK4 Roadheader. The machine offers a large cross section profile with high-powered cutter booms up to 350 kW specifically designed for this demanding market.

Dosco is based in the United Kingdom and designs and manufactures roadheaders, continuous miners and associated conveying systems for mining development and production applications. Dosco also produce a range of roadheaders and boom-in-shield machines for civil tunneling applications with full backup systems. Dosco has served its respective markets for more than 50 years, supplying more than 3,000 machines and exporting to over 50 countries.