While combined sewer systems carry wastewater and stormwater to treatment plants, they can be overloaded during heavy rainfall events. A combined sewer overflow (CSO) diverts excess, yet untreated, water into the environment, potentially causing adverse human health and environmental impacts.
Limits of the current strategies for BOD5 measurement for CSO monitoring:
·Strategy based on a flow-controlled sampler.
·Need power supply on worksite.
·Sample reproducibility & representativeness biases due to average measurement.
·Sample conservation (weekends, public holiday).