Insights

Ever wonder what keeps our community infrastructure running behind the scenes? Let’s talk about the important role of flow monitoring in sanitary sewer systems. This practice can help system owners with capacity planning, leak detection, infiltration and inflow (I/I) detection, asset management, and regulatory compliance.

In the dynamic landscape of community infrastructure, flow monitoring is a vital practice that helps sanitary sewer owners plan, maintain, and optimize a system’s lifespan. This practice anticipates adverse conditions in sanitary networks, helps utilities make informed decisions about their systems, and identifies areas that need improvement within a community's water infrastructure.

What is Flow Monitoring?

Flow monitoring is the process of monitoring the flow of wastewater through the sewer system. This is typically done by using sensors and monitoring devices installed at various points within the sewer network.

The primary purpose is to gather data on the volume and rate of wastewater flow, which is crucial for managing and maintaining the sewer system effectively. This process validates and prevents water-in-basement (WIB) reports while anticipating capacity issues.

It can save money by streamlining future development areas, heading off system surcharges, focusing on future improvements, and diagnosing infiltration and inflow problems. Flow monitoring also helps avoid penalties through compliance with overflow monitoring, EPA consent decrees and other regulatory requirements.

How it Works

The process starts with utility owners establishing clearly defined goals to optimize the management and maintenance of the water collection system. Monitoring goals will vary, but they will aid in capacity planning by providing crucial data on wastewater flow volume and rate, leak detection, and I/I issues. Once the goals are set, the next step is selecting the site for sensor installation.

Two types of sensors are used for data collection: a submerged sensor at the bottom of the pipe to track the pressure and speed of the water or a non-contact sensor to track how much flow is passing through the pipe. Once installed, data is collected over several months to provide a comprehensive understanding of the system's performance. This includes rainfall measurements from rain gauges and flow data under dry and wet weather conditions.

By analyzing these data sets, utilities can detect patterns and identify areas of concern, which can be addressed to prevent system overloads and failures. This data-driven approach allows for informed decision-making for maintenance and improvements, ensuring that the sewer system operates efficiently and can handle significant wet weather events, thereby improving overall system reliability and planning for future infrastructure needs.

Increasing Capacity for Development

The City of Heath, Ohio, established goals for its flow monitoring program to measure existing flows and the system's response to rain to determine available space for additional flows. The city received numerous inquiries from developers and businesses wanting to build and tap into the sewer system. Flow availability became a crucial factor for go/no-go decisions. The data collected also identified neighborhoods and districts that would benefit from I/I reduction projects, ensuring efficient use of the sewer system's capacity.

Preparing for Wet Weather Events

In significant wet weather events, implementing flow monitoring can help communities prepare their systems for future large increases in water flow. By analyzing rainfall data and corresponding flow rates during dry and wet conditions, utilities can identify vulnerabilities in the system. The City of Wilmington, Ohio, implemented a four-month flow monitoring system to segment the city into flow sewersheds, where sewers flow to an endpoint. The collected data will determine dry and wet weather flows to quantify the Rainfall Dependent I/I. The resulting I/I identification and reduction strategy from flow monitoring will help the city identify locations for smoke testing.

This proactive data-driven approach will allow for better preparation and response to significant wet weather to mitigate risks and enhance the resilience of the system.

Costs and savings for any city can be the most significant factor for determining if a city should install a system to collect flow data. Flow monitoring can be a cost-saving measure in the immediate few months to a year after it’s implemented by identifying areas for improvement, preventing costly WIB incidents, and ensuring regulatory compliance. Over the long term, it can lead to further cost savings through optimized system maintenance, reduced risk of overflows, and improved asset management.

B&N is Here to Help

Flow monitoring offers numerous benefits for sanitary sewer systems, including enhanced capacity planning, leak detection and the identification of I/I issues. By providing crucial data on flow volume and rates, it helps utilities optimize asset management and maintain regulatory compliance, thus avoiding penalties.

B&N’s team of collection and distribution engineers are here to help determine how flow monitoring can improve your sewer collection systems. Contact us to learn more about this essential practice.