Client: Anglian Water
Date: 2020-present
Costain, as part of the Strategic Pipeline Alliance (SPA), is delivering hundreds of kilometres of new pipeline for Anglian Water to enhance the East of England’s resilience to climate change and water scarcity.
SPA has installed over 200km of pipeline while exceeding the capital carbon reduction target of 65%, a result of following a PAS2080 carbon management approach and challenging carbon early in the design phase.
The challenge – boost the climate resilience of one of the UK’s driest regions
The East of England is one of the driest regions in the country, with only two-thirds of England’s average rainfall. It is also one of the fastest growing, with potential population growth of one million people by 2045.
Together, these challenges make the Anglian Water region particularly vulnerable to the impacts of climate change, including drought and flooding.
The approach
SPA has been tasked to ensure that clean water can be supplied from ‘wetter’ parts of the Anglian region in North Lincolnshire to ‘drier’ parts, including Cambridgeshire, Suffolk, Norfolk and Essex, without the need for an increase in groundwater abstraction, allowing ecosystems to recover in rivers and chalk streams.
Integral to SPA’s approach has been the adoption of a digital twin strategy. SPA has applied hydraulic models to identify how the existing network could be better utilised to avoid the need to lay new pipes and to optimise the existing and proposed storage.
Other opportunities that were explored to build less included the optimisation of the existing strategic network, importing water from adjacent water companies, 24hr vs 21hr a day pumping and setting triggers to pre-emptively transfer water to where it may be needed. The opportunities provided total savings worth more than £5m each.
The solution – reusing pipework to reduce material use
The solution is reusing 67km of existing pipework, reducing the overall pipe length by 22%, whilst design solutions enabled a 26% reduction of new pumping capacity and a 65% decrease in storage capacity, enabling the use of lower carbon materials and techniques during the construction phase of the project. The digital twin has also helped to justify the reduction of three treated water reservoirs to two ‘tanks.’
SPA’s design and modelling also showed the new water network could be operated more efficiently compared to the project’s baseline calculation, reducing the amount of energy required to pump the water around the network and lowering the whole life carbon of the system.
For the Norwich-to-Wymondham stretch of the pipeline, SPA applied a low-water commissioning technique, comprising of air swab washing and disinfection. By using air for commissioning, water use dropped by approximately 79% from 4.6Ml to 0.94Ml.
“The dedication of our teams from design to delivery has allowed us to support sustainable water abstractions, secure water supply resilience, and achieve challenging carbon targets. We are committed to continuing this hard work throughout AMP8 while delivering the largest water infrastructure project the UK has seen for over a decade, creating a resilient water supply across our region that has minimal environmental harm.”
Andy Alder Managing director of major infrastructure delivery at Anglian Water
The benefits – carbon reduction targets exceeded and forecasted biodiversity improved
SPA’s disruptive approach has resulted in 210,000tCO2e of savings between 2020-2025. Equivalent to a 66.7% carbon reduction across the entire project.
An estimated 165,000tCO2e of savings were achieved through efficient design work, such as re-routing pipelines, using different materials, and optimising pipeline diameters.
Further savings have been achieved during the construction phase. This included the use of v-buckets to minimise the amount of excavated material, and significant work was done to crush and recycle excavated materials as pipe bedding.
Other savings have been realised through the procurement of lower carbon materials, non-infrastructure design and delivery, and trialing of different fuels and installation techniques such as pipe plough.
SPA is also on track to exceed the voluntary Biodiversity Net Gain 10% target – which SPA had already committed to prior to it becoming a legal requirement - on Anglian Water owned land, forecasting at over 15%.
The work of SPA has also been recognised at the following Institution of Civil Engineers awards:
- ICE East of England “Best Project - Sustainability” award
- ICE East Midlands “Carbon and Sustainability” Merit Award
“Together with our alliance partners, we’re delivering new drought-busting pipelines that will improve the region’s resilience as it confronts the challenges of climate change.
Bryan Williams Construction director and framework lead at Costain
“Our award-winning team has pioneered a collaborative approach that resulted in significant reductions in carbon emissions. Throughout AMP8 we’ll be continuing to push the boundaries of innovation and efficiency to deliver on our upgraded carbon reduction targets.”
The numbers
210,000
Tonnes of estimated carbon savings between 2020-2025
15%
Forecasted biodiversity net gain
67km
Existing pipework reused
Next steps - boosting the carbon reduction target for AMP8
SPA is continuing to work collaboratively during AMP8 (2025-2030), when it will complete the pipeline and take its total length to 580km. The carbon reduction targets for AMP8 have been increased to 70% to reflect SPA’s ambition and commitment to creating a resilient water supply across the East of England.
ENDS
Contact
Gerard Shore
[email protected]