Stealing from the market: A novel application of market based principles for real time collection system coordination

For collection systems with independently controlled and operated storage assets, there are opportunities to increase system performance, without the need for any new construction, by implementing asset coordination. Real-time dynamic control and coordination can help the utility of the future achieve cost effective collection system (CS) management and improved performance by implementing a market-based optimization (MBO) approach. Performance is measured as a reduction of overflow activations and volume, surcharging, and flooding. A MBO approach assumes that agents (a collection of monitoring, treatment, and storage control points) are participating in a competitive marketplace. The agents can freely buy/sell conveyance, storage, or treatment capacity with one another. Once trained and implemented, the agents collectively coordinate the best CS management strategy, in real time, and in a non-cooperative manner, to avoid undesired local conditions such as flooding or an overflow. MBO has numerous advantages over traditional static real time control strategies because the CS can perform optimally given any spatial distribution of rainfall. For example, if precipitation is disproportionately distributed over one of three controlled tributary areas, the MBO system will continuously optimize the release of flow into the interceptor from the burdened area and store flow at the other areas, which are not receiving rainfall, to maintain optimal conveyance capacity in the interceptor. Without this coordination, the independent control system at the burdened tributary area would hold back flow until an overflow occurs. The MBO control strategy has been applied to reduce wastewater overflows in the City of South Bend, which has reduced overflows by 3.8M m³. The Buffalo Sewer Authority is in the middle of a stages implementation and is projected to reduce overflows by approximately 1.5M m³. Simulation results are described in detail for a recent project in southern Ohio. Market based concepts are being explored to further improve performance.