Water torrents gush through tunnel amid project challenges

The troubled Snowy 2.0 pumped hydro project has seen torrents of water gushing from a tunnel and an underground cave; because two events that occurred a few days apart show the difficulties faced by contractors.

Videos obtained by this masthead show dramatic scenes of water flowing at high pressure through a tunnel carved by the 205-foot-long drilling machine known as Kirsten, eroding rocks uphill at a 47 percent slope.

In another incident late last month, a temporary malfunction in pumps caused a waterfall-like accumulation of water in part of a large cave excavated for the project.

Leaked videos dramatically show the hurdles the multibillion-dollar project faces beneath Kosciuszko National Park and away from the public eye.

Snowy Hydro, the Commonwealth-owned company tasked with carrying out the project, said the intrusion was the result of naturally occurring geological conditions and was expected during tunneling.

“Although the volume was higher than normal for a short period of time, the water flow depicted is being actively managed on site by prime contractor Next Generation Joint Venture,” it said in a statement. “Underground work continues in the project”

NSW’s workplace safety regulator SafeWork said it was aware of an “issue” with water entering part of the Snowy Hydro 2.0 project and would continue to monitor the condition of the facility. “No injuries to workers were reported in this incident,” the statement said.

Snowy 2.0 involves digging 27 kilometers of tunnels under Kosciuszko National Park.Alex Ellinghausen

The lead contractor of the project, Italian construction company Webuild, directed the questions to Snowy Hydro. Webuild is also building a multibillion-dollar metro rail line to Sydney’s new international airport and has reached a major deal with the NSW government on the project.

Another rig called Florence was an earlier high-profile example of the challenges of the Snowy 2.0 project. In September 2022, the machine got stuck in soft ground less than 100 meters from a 15-kilometer tunnel, leaving a hole in the surface.

Florence was trapped for almost all of 2023, being released in December and making slow progress until February 2024, when she became stuck in solid rock while digging a bend in the tunnel. It took seven weeks for a team of contractors using high-pressure water jets to blow it up.

Since then, the excavation of the tunnel tunnel that will connect the Tantangara reservoir at the high point of the project to the power plant and electricity-generating turbines has continued.

Former prime minister Malcolm Turnbull commissioned Snowy 2.0 in 2017 and announced the completion date as 2021. The initial price tag of $2 billion, announced before the feasibility study was completed, rose to $6 billion by the time the report was completed.

The official price tag was changed to $12 billion in 2023 and the deadline was extended to 2028.

Then in October last year Snowy asked the Webuild-led joint venture building the project to carry out another cost assessment, leading many observers to expect a new boom. But Snowy recently said the 2028 construction deadline is on track.

As inflation pressures increase construction costs and project financing, tunnel workers received a 26.5 percent wage increase in four years in September, pushing their individual salaries to more than $300,000.

Minister for Climate Change and Energy Chris Bowen remains committed to the project, describing it as a key element of Australia’s transition from a coal-fired grid to one dominated by renewable energy.

Snowy Hydro uses excess electricity to pump water up from a reservoir at the bottom of a hill, from where it flows down and turns turbines.

The project is a major upgrade to the existing Snowy scheme; It brings the total production capacity to 375,000 megawatt hours, enough to power 3 million homes for a week.

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