During the final days of 2022, the Environment Ministry greenlit the construction of a highway stretch connecting Rača and Záhorská Bystrica, both boroughs of Bratislava, with a 11.76-kilometre Karpaty tunnel going through the Small Karpatian mountain range.
The tunnel would not be constructed via dynamite, but by a tunnel-boring machine also known as a “mole”. It is a machine used to excavate tunnels with a circular cross section. The Silverton Tunnel under the Thames in London was built via this method, for example. In Slovakia, this system has not been used.
The stretch will be part of the Bratislava bypass currently created by the D4 highway and R7 dual carriageway.
“Although the new D4 highway from Bratislava’s Jarovce to Rača is in operation since November 2021, it still lacks a connection via the Small Carpathians between Rača and Stupava, where it should be connected to the D2 highway leading to Brno,” the Bratislava Self-governing Region (BSK) writes on its website.
The Environment Ministry okayed construction of the stretch in the V3a variant. The ministry sees it as the most favourable in terms of impacts on the environment.
The variant V3a counts on the construction of an above-ground intersection with the I/2 road. The total length of the stretch is 12.417 km, of which the tunnel Karpaty will be 11.760 km. The BSK estimates the time for boring the tunnel tubes to be 22 months. All the construction work should last 5.6 years.
Costs are estimated at more than €1 billion and the most expensive construction in Slovakia. Its construction depends on the availability of finances.