Waste not, want not?

As AMP8 delivers its unprecedented spend, doing more with what we already have will be invaluable, says Stonbury's Ian Mellor. “Water companies should ask what they can reuse and repurpose, rather than building something new somewhere else or on the same site.”

New life can be breathed into treatment assets and service reservoirs, for example, and delivered at a fraction of the cost of building installations from scratch. But these facilities are often very old, which means an overhaul using the latest materials is required.

Leakage and degradation of structures are likely to be issues, says Mellor. “Engineers must provide solutions that eliminate leakage, preventing ingress of contaminants for clean water assets and egress for wastewater structures.” This means enhanced waterproofing is required, using the best technology available.

Some older water facilities are sealed with bitumen, which is carcinogenic, or the concrete walls may have been weakened by soft water, which tends to eat into calcium carbonate in the cement matrix. This can soften the concrete surface, in which case the tank must be refaced with specialist renders and coatings.

Stonbury uses a range of materials from Sika for this purpose, including Sikadur-Combiflex®-933, SikaTop®-581 Seal, SikaTop®-596 Seal, and Sikalastic® M 808 polyurethane coatings for the inside of tanks. “Sika has good technical support, and the ability to develop products to suit client needs, such as for low-temperature application or damp tolerance,” Mellor explains.

A recent project saw Stonbury repurposing an abandoned tank used to supply process water for a paper mill, where the loss of an existing reservoir was putting “huge pressure on the network”, Mellor says. Stonbury sealed and lined the tank using Sika products in an around-the-clock project that deployed heating systems to cure the materials rapidly.

Mellor recalls: “We also installed a new membrane to seal the roof slab from potential ingress as well as upgrading all access points to current security standards. Ultimately the asset was repurposed very quickly and fully satisfied the requirements of the regulator.”

The result was an asset available in weeks compared to the months or years it would have taken to construct something new, at a fraction of the cost and impact on the environment.