Mythe Water Treatment Works

Mythe Water Treatment Works is a major potable water treatment facility located near Tewkesbury in Gloucestershire, England. Operated by Severn Trent Water, it abstracts raw water from the River Severn and serves a significant portion of the West Midlands region. The plant is a critical piece of infrastructure for regional water security, employing advanced treatment processes to meet modern drinking water standards.

History and construction

The facility was commissioned and constructed in 1964 by the former Tewkesbury Rural District Council to address growing demand in the post-war period. Its strategic location on the banks of the River Severn was chosen for reliable water abstraction. Following the reorganization of the water industry under the Water Act 1973, ownership and operation transferred to the Severn-Trent Water Authority, a predecessor of the contemporary utility Severn Trent Water. The plant has undergone several major upgrades, most notably in response to the stringent regulations of the European Union's Water Framework Directive and the UK Drinking Water Inspectorate.

Treatment process

Raw water is abstracted from the River Severn via an intake structure and initially undergoes screening to remove large debris. The primary treatment involves chemical dosing, typically using aluminium sulfate or ferric sulfate as coagulants, within large clarifiers to remove suspended solids and colour. This is followed by filtration through rapid gravity sand filters to eliminate finer particles. A critical secondary disinfection stage utilizes ozonation to destroy microorganisms and break down organic compounds, with final disinfection achieved by adding chlorine to maintain a residual in the distribution network. The process is continuously monitored by sophisticated SCADA systems to ensure compliance with the Water Supply (Water Quality) Regulations 2016.

Water supply and distribution

With a treatment capacity of approximately 150 million litres per day, Mythe Water Treatment Works is a cornerstone of the local supply network. Treated water is pumped into the extensive distribution system of Severn Trent Water, serving a population of over 1.5 million across parts of Gloucestershire, Worcestershire, and the southern West Midlands, including areas of Cheltenham and Gloucester. The plant's output feeds into key service reservoirs and water towers, such as those at Churchdown, helping to maintain consistent pressure and supply resilience across the region, particularly during peak demand or drought conditions as managed under the Environment Agency's Catchment Abstraction Management Strategy.

Environmental impact and management

Operations are conducted under strict permits from the Environment Agency to minimize ecological impact on the River Severn. Abstraction rates are carefully managed to protect river flow levels and aquatic habitats, in alignment with the Habitat Regulations Assessment. The treatment process generates waste sludge, which is treated and recycled for agricultural use where possible. The site also implements energy efficiency measures and participates in Severn Trent Water's corporate commitment to achieve net zero carbon emissions by 2030. Regular ecological monitoring of the river is performed in partnership with organizations like the Severn Rivers Trust.

Operational significance

The plant holds high strategic importance for regional water security and is designated as a Site of National Importance by DEFRA. Its reliability was notably tested during the United Kingdom floods of 2007, when the facility itself was flooded, leading to a major loss of supply and prompting a large-scale emergency response and subsequent investment in flood defences. The works plays a vital role in the Severn Trent Water resource management plan, forming a key link in the interconnected grid that allows water transfer between different source zones to balance supply and demand across the Midlands.

Category:Water treatment plants in England Category:Buildings and structures in Gloucestershire Category:Severn Trent