Biarritz Coastal Area
Biarritz built a new wastewater treatment plant on the southern outskirts of the city. The treated water is discharged into the ocean through this pipeline, consisting of 780 meters of reinforced concrete pipes with an inner diameter of 1.6 meters. The treatment has improved water quality at the nearby world-famous beaches of Biarritz.
- Client: City of Biarritz via SAFEGE
- Period: 2022–2003
- Location: Biarritz coast, France
- Solution: Tunnelling
- Technique: Pressing Through
- Biarritz built a new wastewater treatment plant on the southern outskirts of the city. The treated water is discharged into the ocean through this pipeline, which consists of 780 meters of reinforced concrete pipes with an inner diameter of 1.6 meters.
- From a launch pit 12 m in diameter and 19 m deep on the beach in Marbella, hydraulic jacks forced the drill shield through marl and calcareous layers containing beach boulders.
- Modified polymers prevented the clay-rich marl from sticking and optimized the bentonite lubrication.
A Sustainable Approach to the Project
- SDG 6 – The dredging is part of a coastal water remediation project that is structurally improving water quality near the beaches of Biarritz.
- SDG 11 – The infrastructure protects Biarritz’s public beaches as a living environment for residents and visitors.
- SDG 14 – Discharging treated water through a closed underwater pipeline prevents direct discharge onto the coast and protects the marine environment.
Innovation
For the longest section of the boring operation, we used TUMA: a patented system of computer-controlled automatic theodolites that continuously calculates the position of the drill head and compares it to the programmed axis. For sections of this length, where a laser can deviate due to temperature differences, this system provides greater accuracy.
