Alternate: Democratizing Sewer Capacity Planning and Capacity Assurance through Digital Innovation

Sewer capacity planning involves a detailed assessment of the sewer system's ability to accommodate current and future flows, including wet weather peak flows. This is translated into requirements for surcharging pipes, manhole freeboard and sanitary sewer overflows (SSOs). Historically, capacity planning has been conducted using hydraulic modeling software like SWMM, Infoworks ICM, and others. However, the use of these models is restricted by the need for hydraulic modeling expertise, the cost of the software, and the expense of hiring skilled experts. With an increasing demographic shift away from major cities to towns with smaller infrastructure, issues with sewer capacity are becoming more prevalent. These smaller towns often lack the resources and expertise to effectively manage their sewer systems. To this end, the adoption of innovative technological solutions that simplify the process of sewer capacity planning is necessary. This presentation will discuss the current state-of-the-art in capacity planning and discuss the importance of modernizing the capacity planning methods to suit current needs. We will also present case studies of modernizing capacity planning for utilities and show examples of how utilities can create end-to-end workflows to simplify their sewer permitting, and capacity planning and make data-backed decisions on the permit requests ensuring adequate level of service and complying with state and federal regulations. Capacity analysis is a critical element of sewer permitting. As shown in Figure 1 and Figure 2, providing an intuitive interface for utility engineers and staff to perform capacity analysis and review results while leveraging their hydraulic model using information from permit applications can enable utilities to make decisions on permit applications based on data rather than judgement. Once a permit is approved (Figure 3), it is critical that this flow is accounted for in future capacity reviews. This is typically performed manually and is hard to keep track. However, using digital workflows, all approved permits can be automatically added to the hydraulic models to enable capacity review based on approved capacity usage. Hydraulic models provide precise simulations of wastewater flows and system behavior. However, they are complex, require flow monitoring and are expensive to calibrate. Hence, model development is typically only performed on larger diameter pipes and do not include the smaller pipes. This means that capacity review using hydraulic models is limited and not comprehensive. We will also discuss the development of a hybrid modeling approach wherein a small pipe model using pipe fill equations is connected to a hydraulic model to enable simultaneous evaluation of all pipes in the collection system.