Developer Tideway is working to deliver the 25km tunnel under the River Thames across 24 construction sites in London.
In Tideway's 2018/19 annual report, it was revealed three kilometres of the tunnel have been constructed and four giant tunnelling machines are digging deep below the capital.
The company also unveiled details of its innovative river transport plan which aims to reduce the project's carbon footprint as well as reducing road safety risks and taking pressure off London's road network. It is taking around 200 lorry journeys off the road each day by using the river to transport material. More than one million tonnes of material have now been transported by river, saving more than 115,000 HGV movements. Trials undertaken by Tideway have shown using the river can produce significantly fewer emissions, with a 1,000 tonne barge producing an average of 90% less carbon dioxide than a standard HGV equivalent.
Andy Mitchell, Tideway CEO, said: "With work on the tunnel in full swing, and a continued focus on keeping people safe, our operations this summer will see a major increase in our river traffic.
"By transporting at least 90% of our tunnelling material by river instead of on the road, we are reducing our carbon footprint, as well as reducing road safety risks in London – two key issues for the capital. We are confident our work will lead the way in how businesses in future consider sustainable options for transporting goods and materials.
"While our ultimate goal is to clean up the River Thames, we're also committed to boosting the river economy, increasing jobs and improving safety standards."