The Sunderland Ridge Wastewater Treatment Works (WWTW) is located 15 km west of the Centurion Central Business District and is adjacent to the Sunderland Ridge Industrial Area. Wastewater generated in Centurion, Midrand North and some parts of Tshwane is treated at this works. This area is one of the fastest growing areas in the city.
The total capacity of the works is currently 65 Ml/d Average Dry Weather Flow (ADWF). Aurecon has been tasked by City of Tshwane with upgrading and extending the works by 30 Ml/d to meet projected demand in 2015. This includes the following services:
Project challenges include that the Sunderland Ridge WWTW was developed and extended over a protracted period of time. All extensions employed the best available technology at the time to meet the applicable statutory requirements. Stricter standards for treated effluent from the works forced later extensions to meet a higher effluent standard than that required from the works as a whole.
Aurecon proposed a biological nitrogen and phosphorous removal activated sludge plant that should achieve a P-level of 0,62mg/l and an ammonia level of 2 mg/l during winter months. Provision has been made to pre-precipitate phosphorous from the waste sludge to prevent struvite formation in the existing anaerobic digesters. Dewatering filtrate will also be blended with the pre-precipitation overflow to allow for ammonia stripping.
Due for completion in 2012, this project will ensure the improved efficiency of the Sunderland Ridge WWTW.