Project Location: Harefield Service Reservoir No 3

Posted on in the category Concrete Repair, Utilities.

Protection of Concrete Columns at Harefield Reservoir

Protection of concrete columns and bases suffering from soft water attack


Three Valleys Water is one of the UK’s leading water and sewerage companies serving more than 8 million people in the heart of Britain.

Harefield Service Reservoir No 3 forms part of its network responsible for supplying 2 billion litres of water per day. Circular concrete support columns and bases were suffering from chemical attack and erosion requiring reinstatement and protection from further degradation.

The Solution

Monolevel 844SP, an engineering quality render approved by the Secretary of State for use in contact with potable water, was chosen because of its excellent chemical resistance and impermeability to water even under 10 bar hydrostatic pressure. Specialist contractor, Makers UK Ltd, prepared the concrete back to a sound substrate using high pressure water blasting. The surface was then reprofiled using Monolevel 844SP applied directly to the pre-dampened concrete substrate by steel float at an average thickness of just 3mm. It cures to form a dense impermeable finish, which does not affect the quality of the drinking water.


Three Valleys Water plc


Makers UK Limited


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