A new standard for waste water treatment in South Africa

• The upgrade includes new digesters and advanced technology, doubling the plant's capacity to treat waste water and enhancing treatment capacity. 
• Sustainable energy generation, the plant generates over 800 kW of electricity from methane gas by-products, reducing reliance on external power sources. 
• Innovative engineering solutions, overcame poor ground conditions with expert design reviews and risk assessment protocols, ensuring project success.

Constructed in the mid-1950s with a design capacity for a population of 100,000 people, Darvill’s original Waste Water Treatment Works (WWTW) was a feat of spectacular engineering for the time. With steady increases in the hydraulic load, a 33% spike in the organic load in recent years and a population now of around half a million, this has placed a strain on the plant’s capacity to treat and remove nutrients effectively. Factoring in the Department of Water and Sanitation’s review of the WWTW’s effluent discharge and the reduction to the plant’s discharge limit for ammonia (NH3) since 2010, it was high time the facilities were upgraded. 

The groundbreaking upgrades to the tertiary treatment, biological process, sludge digestion and disposal are allowing the plant to increase capacity for waste treatment, now and in the future, and are setting a new standard for South Africa and beyond.