East Rand Water Care Company (ERWAT) provides bulk wastewater conveyance and a highly technical and proficient wastewater treatment service to some 2,000 industries and more than 3.5 million people who have access to sanitation services. It is currently custodian of 19 wastewater care works, treating a combined capacity of some 696 mega litres of wastewater per day. The majority of the operations are in the Ekurhuleni Metropolitan Council (Eastern Gauteng).
Knight Piésold was appointed by ERWAT to conduct aquatic bio-monitoring at 19 wastewater care works (WCW) on a quarterly basis. The aim of bio-monitoring is to assess the impact of the WCW on the receiving aquatic environment. To comply with the water use licence conditions from the Department of Water and Sanitation, aquatic bio-monitoring, and toxicity testing needs to be conducted downstream and upstream of each WCW. The main roles undertaken include: