The Government has launched a consultation on the draft National Policy Statement (NPS) on water resources infrastructure in England which flags up the potential need for more reservoirs, transfer schemes and desalination plants.

Introducing the consultation, the Department for Environment and Rural Affairs said the government has identified “an immediate need” to increase resilience in the water sector to address increasing pressure on water supplies. The pressure is due to population growth, climate change impacts and the need to maintain sufficient water in watercourses, lakes and wetlands to protect the environment.

The draft National Policy Statement for Water Resources Infrastructure (NPS) sets out the need and government’s policies for the development of nationally significant infrastructure projects for water resources in England.

The Government is pursuing a twin track approach to securing resilient supplies which includes both demand management and new water supplies, such as reservoirs, desalination plants and water transfers. The government also wants the water expects companies to reduce leakage by 15% by 2025 and by 50% by 2050.

Commenting on the consultation, Dr Therese Coffey MP, Parliamentary Under Secretary of State for the Environment said:

“However, even if we are successful in reducing demand and the water industry halves the amount it loses through leaks, we will still need more water for supply. This might be new reservoirs, more water transfers, desalination or making better use of waste water.”

The consultation paper says that water storage systems will be required to support transfers, along with other schemes such as desalination and effluent re-use that provide a high level of resilience to longer term drought periods.

While the draft NPS for water resources is non-site specific and does not identify any schemes, it sets out the following criteria for the three infrastructure types:

• Reservoirs or dams: where it is expected that the volume of water to be held back by the dam or stored in the reservoir will exceed 30 million cubic metres; or the deployable output of the dam or reservoir will exceed 80 million litres per day.
• Water transfers: where the deployable output of the infrastructure to be constructed or altered as a result of the development is expected to exceed 80 million litres per day.
• Desalination plants: where the deployable output of the desalination plant is expected to exceed 80 million litres per day.

New reservoirs likely to play an important role

New reservoirs are likely to play an important role in securing resilient supplies and supporting transfers of water across the country in the future, the paper says and it is “likely that reservoir schemes will feature in water companies’ Water Resources Management Plans.

Reservoirs must be planned well in advance of when they are needed, as it takes around ten years from the decision to build to being able to use the water supplied.

However, it points out that while larger reservoirs can provide a good level of resilience during a short term drought (two years or less), they are not as resilient as other infrastructure types such as desalination or effluent re-use, during longer term drought.

Importance of water transfer schemes to enhance resilience

On water transfers, the paper says these are important for enhancing the resilience of water supplies by improving connectivity between areas of water surplus and those facing a deficit. Overall, there is currently a surplus of water for England, due to surpluses in the North and Southwest outweighing deficits in the South and East.

The paper describes the high degree of regional variability as highlighting the need for a more strategic approach to managing water resources, saying water transfers have an important role to play.

“Transfers can move water from areas of surplus to areas that need it. In some cases this can be through existing infrastructure such as rivers and canals but other channels and pipes and supporting infrastructure may also be required.”

The paper also flags up the National Infrastructure Commission’s (NIC) emphasis on the importance of strategic transfers in meeting resilience needs in its own report on water which set out how a range of studies had all found a positive cost-benefit case for greater transfers and water trading.

Transfers currently only make up a small proportion of total supply (about 4%) – the NIC has suggested that strategic transfers could provide about 700 Ml/d extra capacity to the water supply system. The NIC report also pointed out that the range of locations for other water supply schemes, such as reservoirs, can be enhanced by the improved connectivity provided by transfers.

Referring to the development of Water Resources in the South East group, the consultation document says the Government expects neighbouring water companies to work together when planning resources. Pressures already apparent in the South and the East of the country and the fragmented nature of water supply companies in the South East had led to the formation of the group which already focuses on trading supplies. However, the group “may need to focus on more strategic transfer options to address longer term pressures”, the paper says.

Desalination can provide “unlimited supplies of new water”

Desalination plants currently require high operational energy and face constraints such as managing the impact of discharges from the treatment process which can increase the costs and impact of this type of water resource.

However, the paper says in theory desalination can provide “unlimited supplies of new water” as it “doesn’t rely on rainwater and so is extremely resilient to climate change.”

The process can offer resilience to longer term and extreme droughts, as well as flooding and temperature extremes, for example, where demand rises rapidly. Desalination is widely used on a global scale and technology is innovating and continually developing to deliver cleaner desalination technologies.

Image: Thames Water Beckton desalination plant 

Currently Thames Water operates the only large scale desalination plant in England which takes its water from the Thames estuary. Built at a cost of £250 million by a consortium including Spanish group Acciona Agua, the plant can produce 140-150 million litres of water per day.

However, the water company has been considering three desalination options (whittled down from eight) as part of its Water Resources Management Plan 2019 which have been identified as being feasible:

Beckton STW: Development of a 150 Ml/d desalination plant located within Beckton STW with raw water storage at Gascoigne Way, using brackish estuarine feedwater from the River Thames

Crossness - Waldrist Way: Development of a desalination plant located Thamesmead Industrial Estate Extension - south of Erith Southern Grazing Marshes, using brackish estuarine feedwater from the River Thames capacity of the development ranging from 100Ml/d to 300Ml/d.

Crossness - Erith Southern Grazing Marshes: Originally assessed as a 75 Ml/d desalination plant, located within Erith Southern Grazing Marshes, using brackish estuarine feedwater from the River Thames.

The paper refers to Water UK’s Long Term Planning Framework which estimates that London and the South East might need an additional 150 to 200 Ml/d more desalination capacity by 2065 in order to meet water supply needs.

NPS aims to streamline planning process for nationally significant water resources infrastructure

The aim of the NPS, in setting out the need for the development of nationally significant infrastructure projects and the assessment criteria, is to streamline the planning process for eligible infrastructure.

The consultation is now seeking views on the draft NPS and whether it provides an appropriate framework for the Planning Inspectorate and the Secretary of State to examine and make decisions on development consent orders for nationally significant water resources infrastructure.

The Government is developing the NPS to:

• set out the need for new (or significantly expanded) water resources infrastructure projects by referring to evidence from recent reports such as the National Infrastructure Commission report on water
• set out Government policy on developing new water resources infrastructure, as part of a twin track approach to securing resilient water supplies.

The draft NPS was laid for consideration before Parliament last week - the House of Commons Environment, Food and Rural Affairs Select committee will lead on parliamentary scrutiny.

The Government is also due to separately set out plans for managing demand and to improve water efficiency in the government’s upcoming water conservation report.

Deadline to submit responses to the consultation is 31 Jan 2019.

Click here to download the consultation document

Click here to download the Draft National Policy Statement for Water Resources Infrastructure

Click here to access the consultation online survey