Sundon Water Treatment Facility

The Sundon Water Treatment Facility is a state-of-the-art water treatment plant constructed on the site of the upgraded Sundon Reservoir near Luton. ​ The facility was developed to support Affinity Water’s environmental sustainability goals, including reducing abstraction from chalk groundwater sources and improving the ecological health of rivers. ​ The project involved refurbishing the existing reservoir and constructing a new treatment facility to ensure compatibility with imported water from Anglian Water’s Grafham Water Reservoir. The works included:

Reservoir Modifications

• Construction of a reinforced concrete dividing wall to split the single-cell reservoir into two for improved resilience during inspections. ​
• Installation of new DN800 ABB flow meter and integration with existing and new inlet, outlet, overflow, and washout pipes. ​
• Addition of access hatches, ladders, pipe hop-overs, and overbanding on concrete joints. ​
• Installation of baffle curtains in each cell to ensure adequate chlorine contact time. ​

Chemical Dosing Systems

Sodium Hypochlorite Dosing:

• Destroy chloramines (breakpoint chlorination) and maintain free chlorine residuals. ​
• Bulk storage in GRP tanks with uPVC lining, equipped with pressure instruments for level readings. ​
• Grundfos DDA120 smart pumps used in duty/standby configuration. ​
• Leak detection system with PF Detect dual-contained hoses. ​

Sodium Hydroxide Dosing:

• Reduce LSI by increasing alkalinity and maintaining pH levels. ​
• Bulk storage in HDPE PE100 tanks with temperature control to prevent freezing. ​
• Grundfos DME940 pumps in duty/assist/standby configuration. ​