Service Reservoir Waterproofing – SHOTCRETE 513
See how Stonbury waterproofed a below-ground potable water tank, using SHOTCRETE 513 for rapid application and return to service.
Location: Midlands-based Service Distribution Reservoir
Contractor: Stonbury
Product: SHOTCRETE 513
Application thickness: 10mm to 15mm
Material used: 320 x 25kg bags
Structure type: Masonry-built, below-ground potable water tank / service reservoir
Stonbury required a specification to waterproof a below-ground potable water tank constructed from masonry in a midlands-based service distribution reservoir. Natural Cement reviewed the application and recommended SHOTCRETE 513 as the most suitable solution for the job. Because the tank formed part of potable water infrastructure, material approval and waterproofing performance both mattered from the outset.
The internal tank surfaces presented a demanding substrate. The potable water tank was built from engineering and glazed brickwork, while some areas also carried older cementitious waterproofing materials. As a result, the repair system needed to bond to difficult masonry, create a continuous waterproof lining and suit a full-tank application in a live water-sector environment.
In addition, the specification needed to address internal angles and maintain consistent depth across the substrate. That requirement made application control important, especially where a continuous seal had to be maintained.
Natural Cement recommended SHOTCRETE 513 because it matched the technical demands of the project. SHOTCRETE 513 is a fast-setting dry-spray concrete with rapid strength gain. It also offers waterproofing properties, suits cold and wet conditions, and is approved under DWI Reg.31 for direct contact with potable water.
The product is designed to start setting at around 4 minutes and finish setting at around 10 minutes at 20°C. It is suitable for dry-spray installation from a minimum thickness of 10mm. These properties made it well suited to a reservoir project where speed, durability and return to service all mattered.
Stonbury completed the works inside the service reservoir. First, the team carried out high-pressure water jetting of the brickwork to remove contaminants. They then fixed stainless steel mesh before spray applying SHOTCRETE 513. Immediately after spray application, they finished the material with a trowel.
The technical specification also required extensive surface preparation before application. All previous coatings had to be removed. On glazed brickwork, the joints needed to be raked out and the surface brush hammered or scabbled to create an adequate key. The substrate then had to be clean, dust-free and thoroughly dampened before application.
To support adhesion, the specification recommended mesh reinforcement and required a minimum depth of 10mm over the mesh. For this project, the applied depth was described in terms of 10mm to 15mm.
Across the full tank, Stonbury used 320 bags of SHOTCRETE 513.
The completed works waterproofed the full tank and created a continuous protective lining across a challenging masonry substrate. Just as importantly, SHOTCRETE 513 supported a fast application process and a rapid return to service. The technical specification allowed the structure to return to service after the product had fully set and a minimum curing period of one hour had elapsed.
For asset owners, consultants and specialist contractors, this project shows the value of combining proven potable water approval with spray-applied speed and practical site performance. It also demonstrates how SHOTCRETE 513 can help waterproof service reservoirs and potable water tanks where substrate condition, programme pressure and long-term durability all shape the repair strategy.
Need advice on waterproofing a service reservoir, potable water tank or other water infrastructure asset? Contact Natural Cement to discuss SHOTCRETE 513, request a project specification, or speak to the technical team about a suitable repair approach.
Date added: 07/04/2026