The Public Works Department (PWD) in the City of South Bend, Ind., through its Division of Water Works and Bureaus of Sewers and Wastewater, supplies drinking water and also collects and treats wastewater for a population of 122,000 in the city and surrounding unincorporated areas. Among other things, PWD is responsible for more than 520 miles of water mains; eight water filtration plants; 525 miles of sanitary, storm, and interceptor sewers; a combined sewer system; and a wastewater treatment facility.
Like many cities in the United States, South Bend is challenged with combined sewer overflows (CSOs) during periods of significant precipitation. CSOs result in the release of untreated wastewater to the environment – in this case, the St. Joseph River, which runs through the city – or in residential basement sewer backups when the collection system can't keep up with the runoff generated by bad weather.
To mitigate the problems associated with CSOs, the city and EmNet LLC instrumented the wastewater collection/sewer system and later partnered with IBM to apply a Smarter Water solution. The solution, based on IBM's Intelligent Operations Center (IOC) software, collects city water and wastewater supervisory control and data acquisition (SCADA) system data in near real time. This data includes water levels in the sewer system, rain gauge data, and pump station data to monitor what's happening at any point in time in the wastewater system.
Access to this data from the IBM Web-based cloud system helps PWD address problems before they occur, either through the real-time diversion of stormwater to areas of the collection system that have spare capacity, or by sending maintenance crews out to remove obstructions in the sewer system before there's an overflow or backup to the environment. IOC provides a geospatial view of the whole city water and wastewater system, combining data from the city's geographic information system (GIS) with SCADA information. IOC also includes key performance indicators that give advanced warning to PWD before problems occur. This helps the city by reducing unwanted CSO violations – tracked by the state Environmental Protection Agency – and basement backups. It also saves the city money by helping PWD operate more efficiently, addressing challenges before they become problems.
The PWD uses the IOC on IBM SmartCloud under a Software as a Service (SaaS) subscription model. The solution provides the city with a unified view of its CSO infrastructure, and delivers sophisticated analytics and monitoring capabilities. This IOC implementation was preceded by a proof-of-concept system (PoC) developed by IBM in cooperation with the city PWD.
Initially, the IOC implementation ran in parallel with the PoC system until all data and dashboards were imported from one platform to the other. Key features and capabilities of the IOC system include:
- overlay mapping of key data values for at-a-glance status;
- collection system monitoring for wastewater levels in the collection
system and pumping station operation;
- collection of trending and historical data from water and wastewater
operations for planning;
- basement backup heat map;
- calculation of CSO volumes from SCADA collection system
wastewater levels; and
- system level and GIS view of cross-silo SCADA components.
The IOC implementation for South Bend is largely dependent on data collected from CSOnet, the physical sensor network developed by IBM Business Partner EmNet. As a heterogeneous sensor-actuator network, the CSOnet architecture is a set of local Wireless Sensors and Actuator Networks (WSAN) that connect to an existing wide area network (WAN) through four types of gateway devices:
- instrumentation nodes (INodes) that retrieve the measurement of a
given environmental variable, process that data, and then forward
it to the destination gateway through a radio transceiver;
- relay nodes that help forward the data collected by INodes when
those nodes are more than one hop away from the gateway node;
- gateway nodes that serve as gateways between the WSAN, used to
gather data from the INodes, and a WAN which allows remote
users easy access to CSOnet's data; and
- actuator nodes connected to valves (actuators) that hold back
water in the sewer system.
With the IOC acting as the central point of command, the network collects, analyzes, and monitors live data from sensors and level indicators in the sewer system and also helps control wet weather flow through the remote use of wireless sensors, smart valves, and ballasts, or inflatable bands.
The solution also takes advantage of ArcGIS server software from IBM Business Partner Esri. Since 1999, various departments in the city had been using ArcGIS software to manage geographic data and generate maps for different city projects, such as the hotspot mapping of crime, utility inventory, and mapping city festivals and events. Now, the city has access to its water system information through easily viewable maps with simple color coding. The city also uses residential basement heat maps to track basement flooding and backups in low-lying areas.
In the future, the City of South Bend plans to extend the capabilities of the solution beyond the PWD to support other city services and to promote cross-department integration and communications, including mobile device access to key data.
First in the cloud
South Bend is the world's first city to monitor and control its CSOs with cloud technology. The combined technology – the IOC in concert with the CSONet sensor network – is making a dramatic difference not only in the way the city manages its sewer system, but also on the health of the environment.
The South Bend PWD has substantially reduced the volume of untreated wastewater and pollutants entering the river. Through the use of sensors and level indicators embedded in the 500-mile sewer system, as well as dashboards that indicate the precise hotspots where the risk of wastewater overflow is greatest, city crews proactively monitor the depth and flow of wastewater in the city collection system. This unprecedented ability to predict, respond to, and even prevent incidents before they occur helped the city cut wet weather overflows by 23 percent and virtually eliminate dry weather wastewater overflows – from 27 events per year to just one in the system's first year of operation.
The same strategy applies to basement backups in low-lying areas. Using its new residential basement "heat map" in combination with near-real-time aggregated data, the city can direct utility cleaning crews to areas where they are most likely to be needed.
The collection and aggregation of near-real-time data plus enhanced monitoring and control capabilities also helped the city maximize the storage and conveyance capacity of its sewer system. By keeping St. Joseph River water out of its collection system, the city gained an extra 10 million gallons of capacity, thereby helping the city avoid spending $120 million in additional infrastructure investments plus more than $600,000 in potential government fines.
By delivering the IOC as a service on the SmartCloud platform, the South Bend PWD also realizes additional cost savings related to information technology and asset management. Instead of funding the project through its capital budget, the SaaS model allows the city to pay for the solution from its operational budget, thereby gaining use of the solution faster while avoiding critical capital expenses related to physical infrastructure upgrades and repairs. The increased system visibility delivered by the solution has also helped the city optimize its human and equipment resources. In addition to identifying 15 vehicles that are no longer needed, the city reassigned crews to work on more important projects, instead of driving around in trucks to find the source of a problem.
South Bend's Smarter Water implementation is:
Instrumented – The solution captures data from wireless sensors and level indicators in the sewer system as well as from SCADA devices placed throughout the system. Information is delivered to a central dashboard that can issue alerts to worker PDAs should a problem arise.
Interconnected – The solution integrates and aggregates three data types – geographic, asset, and environmental – from geographically distributed sources and feeds it into the system, giving the city a holistic view of its water and wastewater systems.
Intelligent – In addition to collecting and aggregating data to deliver a unified view of the city's water and wastewater infrastructure, the solution employs sophisticated analytics and monitoring capabilities that help the city predict where wastewater overflows are likely to occur. Sensors and level indicators monitor, measure, and communicate the depth and flow of wastewater throughout the 500-mile collection system. If flows rise to dangerous levels or if a blockage occurs, authorities are immediately alerted to the situation and can take corrective measures, such as deploying repair crews to the affected area or inflating ballasts to divert water to other sections of the collection system with available capacity. By responding quickly and preventing incidents before they occur, South Bend dramatically reduced the volume of untreated sewage and pollutants entering the St. Joseph River and the number of basement backups in low-lying areas.
Carey Hidaka is with IBM Global Business Services, and Bob Montgomery is with IBM Sales & Distribution.