Balancing the needs for water resources

With summer 2022 focusing the public’s minds on climate change and extreme weather patterns in a way previous warnings have perhaps failed to resonate, water companies are increasingly evaluating supply resilience. Binnies water utilities director and All Reservoirs Panel Engineer, Rachel Pether, explores how companies must navigate the changing landscape of drought, PR24 guidance, and environmental concerns, including carbon implications of substantial new supply infrastructure.

For decades now, UK water companies have largely been able to ensure access to a quality water supply readily available to an increasing population with few having to consider extended hosepipe bans in the face of inadequate rainfall or drought.

Of course, there have been exceptions but summer 2022, with its record-breaking temperatures and below-average rainfall, felt markedly different. It’s hard to forget journalists filming (and continuing to film) on locations featuring large areas of sun-cracked earth, the once lush landscape of seriously depleted reservoirs.

For the first time in a long time, customers are asking water companies why they have not spent preceding years planning for the decreasing rainfall in the wake of population growth and increasing demand.

The truth is that water companies are always looking ahead and considering infrastructure investments to support growing consumer demand, and increasingly so in the wake of growing climate change intelligence.

But, as always, infrastructure investment needs to be cautiously balanced. Not only against capital and operational costs and Ofwat guidance, but environmental considerations.

What is the impact of creating the infrastructure associated with the construction of a water transfer system or a reservoir? It is significant, of course, as are the considerable energy costs associated with solutions such as desalination.

Equally problematic is the growing concern associated with river abstraction and the impact on chalk streams and the wider river ecosystem.

In ‘Meeting our future water needs – a national framework for water resources’  the Environment Agency says its assessment of water requirements assumes “around 700 million litres per day of water that comes from unsustainable abstractions” and that this will need to be replaced by other means between 2025 and 2050.

On balance, water companies faced with forecasts of an increasing challenging supply are evaluating two main options to build-in future resilience – reservoir and water transfer system investments. This is alongside the continuing emphasis on cutting leakage and achieving a long-term reduction in water usage.

In a blog called Meeting Our Future Needs for Water, Paul Hickey, director of the Regulators’ Alliance for Progressing Infrastructure Development (RAPID), noted that, for some water companies, reservoirs will be part of the solution.

He pointed to the Havant Thicket reservoir being developed by Portsmouth Water and funded by Southern Water which he notes gained planning permission in 2021 after 10 years in development.

Costing more than £120 million, it is expected to be operational in 2029, holding about 8.7 billion litres of water and supplying around 21 million litres of water each day – enough for about 1,600,000 people. Crucially, he also noted this development will help to protect two of the country’s rarest chalk streams – the rivers Test and Itchen.

With the creation of reservoirs, treatment plants and supporting infrastructure there are a host of considerations.

The vast area required for a reservoir has the potential to displace communities or disrupt people’s lives. Determinations about suitability therefore must be carefully considered to avoid unnecessary upheaval or anxiety. Ideal sites are those with natural building materials, predominantly clay, and, in the case of non-impounding reservoirs (those without a natural stream flowing in to them), relatively flat areas where the water is not fighting the laws of physics.

Alongside the engineering and environmental impact assessment tests and surveys, early stakeholder engagement is, of course, fundamental. Another important consideration is the proximity to consumers so the supply does not have to travel too far.

A major factor in the pro/con balance of creating a new reservoir is, of course, the potential for habitat support. RAPID notes that the  Essex & Suffolk Water 2015 expansion of Abberton Reservoir (after almost a decade of work to store a further 15 billion litres of water and at a cost of £150 million and capacity of 41 billion litres) secured the habitat for a number of important bird species and other wildlife.

RAPID advises it is “working alongside the five regional water resources planning groups, to ensure that we have timely delivery of new infrastructure”, adding that “where necessary, we will assist the regulators in identifying and overcoming potential regulatory and commercial barriers”.

Ofwat provided for large-scale investments to sit outside the regulatory review, which was possibly another reason why significant reservoir construction was not considered by water companies in recent years. It is also expected that development consent orders for such infrastructure development would help to accelerate the planning process for crucial water infrastructure.

One thing is for certain, infrastructure development will become increasingly important.

Perhaps the final word is best left to Ofwat which, in its report ‘PR24 and beyond, Creating tomorrow, together’ states: “Climate change threatens resilience, both of our networks and our water supply. We’re already seeing drier summers, more frequent and intense rainfall, more variable river flows and biological changes in water bodies. In Wales, the projected reduction in summer rainfall by 2050 significantly exceeds the projected increase in winter rainfall. In England, it’s estimated that there is a 25% chance of the worst drought in recorded history within the next 30 years.”

Ofwat recognises its processes need to adapt to support this, adding that this includes the price review frameworks for England and for Wales “to ready them for the future”.

Construction of the significant infrastructure required for the future may very well be unwelcome in certain quarters.  It is, however, crucial, even if water companies are successful with the consumer behaviour change campaigns aimed at resetting our relationship with water.

Finding ways to reduce carbon in these projects and incorporating a nature positive approach is paramount if we are to achieve the right balance.

While it may not have been intentional at the time, many of the reservoirs constructed over the past century now hold significant social value.

With a deliberate approach, it should, therefore, be possible when delivering the current crop of reservoirs, to create even greater social value, both for present and future generations.