Kwanobuhle Wastewater treatment

Kwanobuhle, a large township on the outskirts of Uitenhage in the Eastern Cape, had a  wastewater treatment works that were long overdue for refurbishment.

Projects of this nature are often overlooked, however, given the magnitude of the impact of these works on the community, the decision was taken to refurbish the WWTW. Access to clean water is, after all, a basic human need.

Wastewater treatment is a process used to remove contaminants and convert it into an effluent, which can be returned to the water cycle with minimum impact on the environment. In municipalities, this process takes place in water treatment plants, where pollutants are removed and broken down. This recycling plays a vital role in the use and sustainability of scarce resources.

Ibhayi Contracting took on the responsibility of rehabilitating the Kwanobuhle Wastewater treatment plant. The project began in January 2019 and is expected to be completed 18 months later in July 2020.

The rehabilitation process which ordinarily is no easy task, was made simpler using Sika products. The concrete spall repairs on the plant were conducted using two products: SikaTop Armatec-110 EpoCem reinforcing protective coating and the Sika Monotop-615HB high build repair mortar. The latter being a repair and reprofiling mortar for structural concrete. The aerators and digesters were also lined with Sika Monotop-612 by trowel application, to reprofile the concrete surfaces. Sikagard-720 EpoCem, a protective coating, was subsequently applied as a 2mm thick layer to the Sika MonoTop-612. Sikaguard 720 Epocem is a thin film sealer, made from epoxy and cement-based fillers, used on vertical and horizontal surfaces. It is a unique product that provides concrete protection and acts as a moisture barrier to allow for the rapid application of an epoxy coating onto surfaces with high moisture contents.

Sikagard-63N epoxy, a high chemical-resistant coating, with a long track record in wastewater treatment plants, was applied to complete the buildup. Finally, all joints in the structures were sealed with Sikaflex Pro 3i and Sikadur Combiflex.

Given the state of disrepair of the WWTW, it was achieving nowhere near full capacity. Project challenges were inevitable expectations and most, such as labour disputes, were dealt with readily. However, once the digesters and aerators are complete, all would have been achieved to ensure project success. The community of Kwanobuhle can look forward to this redevelopment as it is surely one that will stand the test of time; and is certainly…not a waste.


Sika is a specialty chemicals company with a leading position in the development and production of systems and products for bonding, sealing, damping, reinforcing, and protecting in the building sector and motor vehicle industry. Sika has subsidiaries in 100 countries around the world and manufactures in over 300 factories. Sika employs more than 25,000 people and generated sales of CHF 8.1 billion in fiscal 2019. At the end of 2019 Sika won the Swiss Technology Award for a ground-breaking new adhesive technology.

View more