Sika has supported a programme of sewage works in Wallsend, north Tyneside.

The Howdon sewage treatment works site is owned by Northumbrian Water and is the largest of its kind on England's east coast between Edinburgh and the River Thames.

As part of a £15 million upgrade at the plant, sewer pipes, chambers and tanks required the application of a proven corrosion management system to improve long-term performance and structural integrity.

Sika's abrasion-resistant system MonoTop®  4400MIC was selected for the project.

Containing calcium aluminate chemistry, a vital ingredient that induces a 'bacterio-static effect' to inhibit acid generation at source, MonoTop® 4400MIC offers superior resistance to biogenic corrosion which can destroy up to 25mm of concrete per year. This dry-spray solution not only offers high abrasion resistance, post application its high early strengthening means services can be returned to operation after one hour. For the Howdon project, repairs carried out by contractors, CRL, involved applying the sewer pipes, chambers and tanks with SikaCem®-133 GP Gunite. The dry-sprayed micro repair concrete, which was applied at 20mm, provides the ideal restorative solution for a range of structures including tunnels, bridges and fire-damaged buildings. MonoTop® 4400MIC was then applied as an overlay at 30mm thickness. Due to its aluminate cement and aggregate composition, its elements combine to increase its excellent resistance to harmful sulphates. The system adores water, which means it readily adheres to damp concrete surfaces and eliminates osmotic issues with epoxy or polyurea systems.


MonoTop®  4400MIC's rapid-apply qualities, coupled with its supreme curing time, meant its installation was completed in three days, with the plant remaining fully-operational at all times. This simple, cost-effective solution has eradicated the debilitating effects of corrosion to guarantee the functionality of vital elements within the wastewater treatment plant. By eliminating the need for additional maintenance visits, MonoTop® 4400MIC well deserves its reputation as a robust, industry-leading concrete corrosion inhibitor.

(CM/MH)