water management

Climate change makes sustainable water management more important than ever

By | Engineering for humanity | No Comments

Whether it’s under a lake, a river or the streets of a city, Salini Impregilo is ready for whatever job needs doing to help clients improve people’s lives.

This is especially the case when it has to do with water, a sector where its leadership was confirmed for a fifth year in the latest global rankings published by Engineering News-Record (ENR), the US trade publication.

As the world’s climate changes, this most precious of resources is becoming even more precious. So much so, that the management and treatment of water has also assumed greater importance. This is not lost on Australia, which has had its fair share of droughts, floods – and everything in between.

With decades of experience, Salini Impregilo helps cities manage heavy rainfall, treat wastewater and make seawater drinkable. It also harnesses the flow of rivers to generate electricity and light up the homes of countless communities. Briefly put: it makes available everything that water has to offer.

For decades, Salin Impregilo’s dams have helped communities thrive in the most sustainable way possible, producing electricity without the harmful emissions that come from other forms of energy production. In Australia, it will be building Snowy 2.0, the expansion of the Snowy Mountains Hydro-Electric Scheme that will provide the storage and on-demand generation needed to balance the growth of wind and solar power and the retirement of Australia’s ageing thermal power stations. The electricity produced will also support the push towards sustainable mobility, whether it be in the form of light rail transit or electric vehicles.

In the United States, it helped Las Vegas secure its water supply in case of drought by excavating a 4 km-long tunnel under nearby Lake Mead. This record-setting project saw it bring the tunnel to a pipe at the bottom of the lake. The water drawn by the pipe is pumped to a treatment plant on shore and then sent to the city. This has made the pipe – known as the Third Intake – the main supplier of water because two other pipes near the lakeshore risk going dry whenever the water level goes down in times of drought.

And when potable water is hard to come by, Salini Impregilo extracts it from the sea by means of desalination. In Dubai, the Jebel Ali M is an icon for the sector because it was the largest such plant in the United Arab Emirates at the time of its completion. With a capacity of 140 million gallons of water per day, its eight desalination units provide nearly all of the city’s potable water.

Of droughts and flooding rains

Sometimes the problem is too much water, such as when heavy rainfall overwhelms a city’s sewer system. In Washington, D.C., Salini Impregilo is excavating its second tunnel for a project to expand the system to reduce the amount of untreated stormwater and sewage that flows into nearby rivers during a storm.  Known as the Northeast Boundary Tunnel, it is the biggest component of the Clean Rivers project. By helping reduce combined sewer overflows by 98 per cent and the chance of flooding in the areas it serves from about 50 per cent to 7 per cent in any given year, it will help improve the quality of the water in the nearby Anacostia River.

In some cases, the river is polluted for reasons other than combined sewer overflows. Victim of decades of industry abuse, the Matanza Riachuelo River Basin near Buenos Aires, Argentina, is among the most contaminated in the world, putting at risk the health of millions of people. Part of a massive project supported by the World Bank, Salini Impregilo is building a pre-treatment wastewater plant, pumping stations and an evacuation tunnel to help clean it up. At a capacity of 27 cubic metres per second, the plant will be one of the biggest of its kind in the world. The water it treats will be flushed through the 12-kilometre tunnel into the River Plate where the basin empties.

Respect for the environment is a tenet that Salini Impregilo has and will always uphold in everything it does, especially when it has to do with water. It is the kind of respect that it has found in Australia, where efforts are made to grow in the most sustainable way possible. And as these efforts accompany the ambitious investments being made in infrastructure, Salini Impregilo will be there to help.

The World Engineers Convention 20-22 November in Melbourne is about engineers coming together to solve some of the world’s most pressing problems.

To learn how you can help build a better world, register here

Budj Bim named to UNESCO World Heritage List

Budj Bim, a 6000-year-old Aboriginal engineering site, earns World Heritage status

By | Engineering for humanity | 4 Comments

One of the finest examples of ancient aquaculture and hydraulic engineering is right in Australia’s backyard. 

After a decades-long campaign by the Gunditjmara people, the Budj Bim eel traps have become the first Australian UNESCO World Heritage site to be listed exclusively for its Aboriginal cultural values.

The eel traps at Budj Bim comprise a vast network of weirs, dams and stone canals to manipulate water levels in various lake basins. Some of the channels are hundreds of metres long and were dug out of basalt lava flow. 

These structures force eels and other aquatic life into traps as water levels rise and fall. The canals also appear to have been used to create holding ponds to keep eels fresh until they were needed for food. Not only did this provide the region’s Gunditjmara people with a year-round food supply, it was also important for trade. 

The site also features the remnants of almost 300 stone houses — the only remaining permanent settlement built by an Indigenous community in Australia. 

Located in southwest Victoria, Budj Bim has been carbon dated to 6600 years old, meaning it predates more internationally well-known examples of ancient engineering like the Egyptian pyramids or Stonehenge. 

Aborginal activist Burnum Burnum said these traps are a prime example of how complex and varied the Aboriginal economy was at the time. 

“Gradually it is dawning on the outside world that life in the traditional Aboriginal way involved a great deal of knowledge and skill,” he wrote.  

Budj Bim is managed by the Gunditj Mirring Traditional Owners Aboriginal Corporation. Gunditjmara Elder Denise Lovett called this a very special day for the community.

“This landscape, which we have cared for over thousands of years, is so important to Gunditjmara People,” she said. 

“The decision also recognises Budj Bim’s significance to all of humanity. We are so proud to now be able to share our achievements and story with the world.”

Gunditjmara Elder Denis Rose agreed, saying the ingenuity of their ancestors “shows in the aquaculture systems that are still operational to this day”. 

Traditional owners had been petitioning for the site to receive World Heritage Listing for some time, and hope to restore the site to what it would have looked like before European colonisation.

Tae Rak (also known as Lake Condah) was drained in the mid-20th century to create land for grazing, and so water can only be seen in the channels during very high floods. The site has also been damaged by vandals and livestock over the years. 

The Victorian Government has committed $5.7 million for preserving Aboriginal heritage in the state, and restoring Budj Bim is a large part of that. It’s expected that Budj Bim’s World Heritage listing will now turn the world’s attention to this millennia-old site. 

The announcement was made at a ceremony this past Saturday in Baku, Azerbaijan. In recommending Budj Bim for World Heritage listing, the International Council on Monuments and Sites acknowledged the Gunditjmara People’s involvement and leadership in nominating the site for inclusion on the World Heritage List.

Budj Bim has also been recognised by peak body Engineers Australia as one of the country’s top engineering achievements. Engineers Australia CEO Peter McIntyre said the UNESCO World Heritage listing is welcome news, and highlights the important contributions of Australia’s first engineers.

“Budj Bim is an extraordinary feat of engineering by the Gunditjmara people. For thousands of years, engineers have been using the tools available to them to improve lives and build communities,” he said.

Budj Bim is now Australia’s 20th property on the UNESCO World Heritage List. Other sites include Uluru, the Great Barrier Reef and the Sydney Opera House. 

You can take a guided walking tour of the Budj Bim National Heritage Landscape as part of the upcoming World Engineers Conference, held 20-22 November in Melbourne.

Register here for the Great Ocean Road and Budji Bim Cultural Tour

Register here for WEC