Daugava tunnel

Project description

The city Riga is a major seaport and a cultural and industrial centre with more than one million inhabitants. Due to economic growth the amount of traffic increases fast and the capacity of the existing river crossings is to low. To meet the expected traffic growth, a new Northern extension of the ring road was planned including a new river crossing with 2 x 3 lanes.
The Daugava Tunnel project is an 8 km highway link, starting at the east bank with an approach road of 2250 m with several junctions and connections to the existing road network, an immersed tunnel part with a length of approximately of 1300 m and an approach road on the west bank of the river of 4500 m, also with several connections and crossings with the existing road network. Both a concrete immersed tunnel as a steel shell tunnel was designed.

Scope of work

Design Engineer and Employer's representative for all the aspects of the project during the feasibility phase and the tender preparation phase, including:

• Quick scan of a high cable stayed bridge, bored tunnel and an immersed tunnel
• Preliminary design
• Basis of design
• Employer's requirements for the Approach roads
• Employer's requirements for the Tunnel Civil Structures
• Employer's requirements for the Tunnel Electrical and Mechanical Installations
• Employer's requirements Definition Drawings
• Employer's requirements, Quality System

The design works included the following:

• Concrete immersed tunnel and approach roads
• Steel shell tunnel as an option
• Casting basin
• Building aspects, construction stages
• Cross overs
• Dredging works
• Reclamation works
• Environmental aspects
• Contaminated soils
• Approach roads
• Viaducts and bridges
• Alignments of all the roads
• Port and quay wall crossings
• Rail way crossings
• Electrical and mechanical installations
• Cables and pipelines
• Operation and maintenance
• Land requirements and compensation costs