Kohlberg Tunnel in Pirna: Construction delays endanger completion!

Kohlberg Tunnel in Pirna: Construction delays endanger completion!

Pirna.The Kohlberg Tunnel, a central element of the Pirna southern bypass, will not be completed by the end of 2024 as planned. The tunnel, which stretches over 300 meters and connects the region with a 3.8-kilometer-long route, is facing unexpected delays. The construction, which has been progressing since 2017 under the supervision of the German Unity Fern Roads Planning and Construction GmbH (Deges), is hampered by the fragile nature of the mountain and the lack of a crucial aid.

Since the tunnel was opened in September 2020, construction workers have already removed 50,000 cubic meters of rock. But the challenges are enormous: In order to concrete the inner shell of the tunnel, several complex auxiliary structures are necessary. Construction supervisor Ulrich Gawlas reports that the last mined block was recently completed, but the open vaults on the west side are now taking additional time. The curing trolley, essential for drying the concrete, has been dismantled, slowing the work considerably.

Delays due to construction

The open vaults require counter formwork and take more time because the curing car is not rebuilt. Gawlas explains that the freshly concreted vaults must now remain in the formwork for at least three days before the formwork truck can move on. “Unfortunately, this costs valuable time,” he says, confirming that the original goal of completing the tunnel shell construction this year cannot be achieved.

Meanwhile, work on the retaining walls in front of the tunnel portal continues. Next year, a company building will be built that will house the control technology for the tunnel. The entire southern bypass is now scheduled to be completed by the end of 2026 at the earliest, which is testing the patience of residents and road users.