Client:
MWC – Mekorot Israel National Water Company
Construction period:
2016 – 2022
City/Country:
Jerusalem, Israel
Contract value:
€ 178,8 million
Jerusalem's Fifth Water Supply Line
Israel
Securing water supply through underground infrastructure
Designed for a service life of 90 years, this major water infrastructure project features Israel's longest tunnel construction. The tunnelling advance progressed beneath a nature reserve. Steel pipes measuring 2,6 metres in diameter were engineered for hydraulic pressures of up to 38 bar.
Sophisticated logistics facilitated the handling and placement of 12- to 13-metre-long pipe sections with a total steel weight of 14.170 tonnes. Reinforced shotcrete encased the pipes outside the tunnel to increase their weight and reduce buoyancy during concrete backfilling. Special in-situ concrete, totalling 62.600 cubic metres, filled the gap amid the tunnel and steel pipes.
Three large caves with volumes of up to 3.200 cubic metres had to be filled before TBM tunnelling could proceed. Above-ground works consisted out of a 430-metre open trench, 4.500 cubic metres of reinforced-concrete backfilling and the installation of 500 tonnes of steel pipes. Successful execution demonstrated advanced expertise in mechanised tunnelling, high-pressure pipeline engineering, underground logistics and complex concrete works.
Scope of Work
- Tunnel boring and cave filling
- Steel pipeline installation
- Hydraulic design
- Shotcrete and concrete works
- Open trench construction and reinforced-concrete backfilling