Barsham WTW (2026)
Barsham WTW: New treatment stream and on-site reservoir - Courtesy of Farrans
Barsham Water Treatment Works (WTW) is located in north Suffolk and supplies drinking water to Lowestoft, Beccles, Bungay, Shadingfield, Ilketshall and the surrounding communities. The site comprises two independent treatment streams including raw water abstracted from the River Waveney and groundwater abstracted from a series of production boreholes. Together these streams provide a deployment capability of approximately 30 MLD and form a key component of the wider Suffolk supply strategy.
Project need
Originally commissioned in 1955 and benefiting from significant upgrades in the following decades as domestic and non-household demand increased, the Borehole Treatment Stream was nearing the end of its extendable life. Asset condition surveys, hydraulic assessments and strategic studies consistently concluded that the ageing infrastructure was impacted by hydraulic constraints and deteriorating asset health, that was restricting deployable output significantly.
The site also presented a significant resilience challenge. Existing treated water storage capacity was limited to roughly 2.5 ML, equivalent to only 20–30 minutes of storage during peak demand conditions. In the event of a prolonged treatment works outage, prior to the upgrades that have been delivered, many thousands of properties could potentially experience interruption to supply. Furthermore, should the River Treatment Stream become unavailable, the restricted capacity of the existing Borehole Treatment Stream meant that customer demand may not be fully met at peak times. These issues are addressed by this investment.
The need for investment was recognised through the North Suffolk Zonal Study and subsequently formed part of Essex & Suffolk Water’s wider resilience strategy. As part of the PR19 Final Determination, Ofwat accepted the company’s case for enhancement funding to increase resilience through the provision of strategic storage at Barsham and improvements to the treatment process.
Existing Barsham WTW – Courtesy of Essex & Suffolk Water
Project drivers & optioneering
The principal driver for the project was the need to improve security of supply for customers across north Suffolk while addressing long-standing operational and asset health risks. The project sought to provide sufficient treatment capacity to utilise the full licensed groundwater sources, improve resilience against outages affecting the river treatment stream and significantly increase treated water storage available at the site.
Several options were assessed during project development, including a do-nothing scenario, refurbishment of the existing bores process, construction of a replacement treatment stream within the operational site boundary and development of an entirely new treatment process on adjacent land. The refurbishment option was discounted due to the condition of the existing assets and the significant operational constraints associated with maintaining production while undertaking extensive reconstruction works.
The solution
The preferred solution was the construction of a new treatment stream, strategic storage reservoir and treated water pumping station on newly acquired land adjacent to the existing treatment works. This approach provided sufficient space for future-proofed infrastructure, enabled construction activities to be segregated from the live operational site, simplified integration and delivered opportunities for biodiversity enhancement and future expansion.
The acquisition of the adjacent land also created the opportunity for a dedicated temporary construction access road, significantly reducing safety and operational risks associated with construction traffic entering the existing treatment works.
Existing Barsham WTW – Courtesy of Essex & Suffolk Water
Barsham WTW: Supply chain – key participants
- Project delivery: Farrans
- Project design & consultancy services: AtkinsRéalis
- Process, M&E installation & MCCs: TES Group
- Design & construction of precast service reservoir: FP McCann
- Reinforced concrete construction: Murform Ltd
- Building steelwork & cladding: AC Bacon Engineering
- Kiosks: Morgan Marine
- Above-ground water storage tank manufacture & installation: Balmoral Tanks
- Chemical dosing installation: Ross Shire Engineering (RSE)
- Chemical tanks: Forbes Technologies Ltd
- RGF aeration system/grids: Cadar Ltd
- Air blowers: Aerzen Machines
- Backwash pumps: Grundfos Pumps Ltd
- Lamella clarifiers: Nordic Water/Jacopa Ltd
- High lift pump sets: KSB Limited
- High lift pump sets: Xylem Water Solutions
- Above-ground pipework: Freeflow Pipesystems Ltd
- Reservoir pipework: Advanced Engineering Limited
- Valves & penstocks: Industrial Valves Ltd
- Flow control & Instrumentation: IFM
- Access steelwork (stairs/platforms): Graham Steelwork & Engineering Ltd
- Access steelwork (stairs/platforms): Steelway Fensecure
- Generator: Edina UK Ltd
New Bores Treatment Stream
At the heart of the investment is the development of a new groundwater treatment process designed to treat the full licensed abstraction capacity of the production and reactive use boreholes.
Raw groundwater enters the process via a new aeration stage. The aeration system introduces air into the raw water stream to oxidise dissolved contaminants commonly associated with groundwater sources, creating conditions suitable for downstream removal within the filtration process.
3D model of the new WTW and pumping station – Courtesy of Essex & Suffolk Water
Following aeration, the water passes through a new two-stage rapid gravity filtration system. The filtration process removes oxidised metals and suspended solids while providing a robust and proven treatment solution capable of consistently achieving the required treated water quality standards. Rapid gravity filtration was selected due to its operational reliability, performance and suitability for treating the site’s groundwater characteristics.
To maintain filter performance, the plant incorporates dedicated backwash systems including washwater storage, backwash pumps and air scour blowers. Filter backwash water is collected and managed through a washwater treatment system, with polymer dosing provided where required to improve settlement and discharge quality.
Treated water from both the new bores treatment stream and the existing river treatment stream is then combined within a common wet well arrangement before being transferred to new disinfection contact tanks. These tanks provide the required contact time to achieve Regulation 26 compliant disinfection while accommodating the site’s maximum treatment throughput.
A new lamella clarifier process has been installed on the filter washwater system to enable further treatment and recovery of process water to further reduce abstraction impacts.
The resulting process provides a resilient, modern treatment facility capable of utilising the full available groundwater licence while supporting operational flexibility across the wider Barsham site.
Strategic treated water storage
A fundamental component of the scheme is the construction of a new twin-cell treated water storage reservoir.
Prior to the project, the site possessed only limited storage capacity, creating a significant vulnerability to supply interruptions. The new reservoir dramatically increases the site’s resilience by providing strategic storage between treatment and distribution, allowing customer supplies to be maintained during operational events, planned maintenance activities or treatment process interruptions.
The reservoir forms a key part of the wider Suffolk resilience strategy and was a specific enhancement commitment identified through the PR19 process. Once operational, it will provide many hours of strategic storage for customers supplied directly from Barsham, reducing the likelihood and impact of supply interruptions while improving operational flexibility across the network.
(left) The new twin-cell reservoir and (right) Inside the new water storage reservoir – Courtesy of Essex & Suffolk Water
High lift pumping station and network integration
A new treated water pumping station was required to distribute water from the storage reservoir into the regional supply network.
The installation incorporates high-lift pump sets configured to provide both operational resilience and future network flexibility. The design accommodates both chloraminated and chlorinated distribution strategies whilst retaining provision for future expansion should network demands increase.
By integrating the new pumping station with both treatment streams and the new reservoir, the project creates a significantly more resilient supply arrangement capable of responding effectively to changing operational conditions.
Construction delivery
Delivery of the project presented a number of significant engineering and logistical challenges.
Maintaining continuous operation of one of Suffolk’s more important treatment works throughout construction was a critical requirement. To minimise operational interfaces, a dedicated construction compound and temporary access route were established on the newly acquired land adjacent to the treatment works. This created a clear separation between construction activities and live operational assets, improving both safety and programme certainty.
The new infrastructure has been constructed largely independently of the existing process, allowing extensive commissioning and proving activities to be undertaken prior to final integration with the live system. This approach minimised risk to customer supplies and reduced the potential for programme delays associated with operational constraints.
The project has been delivered by Farrans on behalf of Essex & Suffolk Water and represents one of the largest investments in water supply infrastructure currently being undertaken in Suffolk.
3D model of the upgrade & storage project – Courtesy of Essex & Suffolk Water
Innovation, sustainability & carbon reduction
Throughout project development, the team actively pursued opportunities to improve efficiency, reduce carbon and enhance environmental outcomes.
A collaborative value engineering process identified more than £1.3 million of potential efficiencies through design optimisation, standardisation and construction innovation. Notable measures included the use of interstage pumping arrangements to reduce excavation requirements, re-use of existing infrastructure where appropriate and optimisation of electrical and process layouts.
The project also benefited from the acquisition of additional land which enabled biodiversity enhancement measures to be incorporated into the development. The increased site footprint provided opportunities to exceed biodiversity requirements while also creating flexibility for future resilience investments across the Suffolk region.
Importantly, the investment improves environmental resilience by enabling greater flexibility of the site’s licensed bore and river abstraction sources. This reduces dependency on river abstraction during operational events and helps protect the River Waveney environment while maintaining reliable customer supplies.
Project outcomes & benefits
The completed scheme will transform the resilience of water supplies across North Suffolk.
The new process is capable of treating the full licensed groundwater abstraction volumes, removing a long-standing operational constraint that previously limited deployable output. Combined with the new reservoir and pumping station, this significantly enhances the site’s ability to maintain customer supplies during planned and unplanned events.
The investment directly supports the many thousands of customers served by Barsham WTW and contributes to the wider strategic objective of strengthening resilience across the Suffolk supply system. It also supports future regional growth and reinforces Barsham’s role as a hub within Essex & Suffolk Water’s long-term resilience plans.
Conclusion
The £52m Barsham Bores Stream Upgrade and Storage Project represents one of the most significant investments in water supply resilience undertaken in Suffolk in recent years.
By replacing ageing treatment infrastructure, unlocking the full licensed capacity of the site’s groundwater sources, constructing a new treated water reservoir and delivering a modern high-lift pumping station, the scheme addresses long-standing operational risks while safeguarding supplies for Essex & Suffolk Water customers.
As the project enters its final commissioning phase, it will provide Essex & Suffolk Water with a modern, resilient and future-ready treatment facility capable of supporting customer demand, environmental protection and future growth across north Suffolk for decades to come.
