Intelligent Water Capabilities Improve San Francisco’s Aging Infrastructure

Water utilities face aging infrastructure, declining revenues, increasing service level expectations and many regulations. In addition, resources for water and wastewater capital programs are limited, which makes infrastructure modernization, expansion and technology upgrades difficult. Utilities can address these critical challenges while delivering the best return on investment to ratepayers or private sector investors. In many instances, utilities cannot easily raise water and sewer rates or purchase new equipment. They must become as efficient as possible with the assets they have. To make the best decisions for planning and optimization, they must look at their operations holistically to understand and predict what is happening with their equipment and operations. The technology and solutions are available. They revolutionize what is possible for water and wastewater utilities. Through integration of business and automation systems and platforms, relationships between the data can be connected. Intelligence can be delivered to the right people at the right time. Some fully integrated systems can predict what is going to happen. In these systems, machines, data, insights and people are connected. In the water industry, a fully integrated system is key to helping large, city-based systems and small rural utilities harness software quickly and affordably. For example, the San Francisco Public Utilities Commission (PUC), a department of the City and County of San Francisco and the third largest municipal utility in California, provides drinking water and wastewater services, hydroelectric and solar power to 2.6 million residential, commercial and industrial customers throughout the San Francisco Bay Area. This article discusses how this utility improved its operations and service with a fully integrated system.

The Water Distribution System

The water entering the system is among the purest in the world, starting in the Sierra Mountains of Northern California, where water is captured from spring snow melts and stored in the Hetch-Hetchy watershed, an area of Yosemite Valley. The San Francisco PUC operates a large and complex water transmission and treatment system that moves water from the Hetch-Hetchy reservoir to the San Francisco Bay Area through a series of reservoirs, pipelines and treatment systems. The system operates with only a few pumps and is sustained almost completely on gravity to move the water more than 200 miles. Since no filtration is required, the water is provided directly to residents. This is not always practical, however, so water is also diverted to a number of reservoirs throughout the San Francisco Area to be used as needed. Watersheds in close proximity also feed these reservoirs, and any water that comes from them is filtered in two larger California water treatment plants: the Harry-Tracy Treatment plant in San Bruno and the Sunol Valley Treatment plant in Sunol. Each can produce up to 180 million gallons per day (MGD). The San Francisco PUC saved $1.3 million by standardizing on a high-availability solution that delivers results for a sustainable advantage. It connects the equipment to processes, data and people—anytime and anywhere—for smarter, faster decisions across the utility. Built on a scalable, synchronized, hot-standby redundancy control platform, this solution ensures uninterrupted control of applications and processes with total transparency. The technology provides enhanced speed and performance, increased memory, built-in hardware redundancy and ease of use. A modern controls infrastructure allows end users to link data from multiple platforms, such as:

• SCADA systems
• Computer maintenance management systems (CMMS)
• Financial systems
• Automated meter reading (AMR)
• Geographic information systems (GIS)

This is critical because it provides the foundation to combine all the utility’s data from standalone and disconnected platforms, allowing robust communication and the movement of data between multiple platforms. To maximize efficiency and data dissemination, a system requires a controller with the appropriate input/output (I/O) connections, starting with an I/O network using PROFINET, which is designed to be ultra-fast and easy to set up. With this type I/O flexibility, utilities can connect to a full range of I/O from simple discrete to safety and process I/O. In addition, high-performance computing at the controller is critical for collection and dissemination of process and operational data. Configurations such as modular industrial PCs in a stack with programmable logic controllers (PLCs) provide a control and computing solution capable of running a human/machine interface, historian, analytics and other higher-level applications. Furthermore, a modern control infrastructure helps minimize failure and obsolescence risks. Today’s controllers are Ethernet-based, featuring high availability redundancy, expandable open architectures, upgradable central processing units and cloud-based capabilities to help drive uptime, flexibility and longevity. In the San Francisco PUC’s case, rather than arbitrarily removing water infrastructure technology and equipment based on a generalized timeline of when these water assets may require replacement, adding layers of technology to the equipment allows the assets to communicate better with their operators help extend the life of these expensive pieces of equipment. The senior engineer of the PUC in San Francisco likened this upgrading process to “pulling out a brain and putting in a new one”’ in just a matter of hours, compared to months or years of rebuilding.

Real-World Results

Downtime was virtually eliminated because of robust, dual-redundancy capabilities, which are imperative for the San Francisco PUC because it has to ensure that water and essential services are delivered 100 percent of the time. The controllers have dedicated, redundant links to one another and operate synchronously with little overhead added to the control application—transferring all the application’s variables, status and I/O data on every scan with speed and transparency. It synchronizes the system at the beginning and end of each logic scan execution to keep all variable data the same—providing rapid and bumpless switchover. The San Francisco PUC is also saves time and money by protecting investments with flexible, scalable, open architectures that also support legacy applications—now and in the future—and reduces engineering costs with easy configuration and quick startup and maintenance. Complementing the time and money savings is an increase in productivity that results from fast, powerful synchronization and the ability to maintain individual system components without interruption. Another benefit of implementing the high-availability solution is that the water treatment plants decreased the cost of spare parts. When the U.S. is losing about 7 billion gallons of treated water per year because of the country’s aging water infrastructure, flexibility could make a substantial difference. Additionally, the smaller form factor of the solution allows for more water capacity. Efficiency gains are also realized through high-speed memory sharing, which enables multiple devices to transfer large amounts of data over a fiber optic deterministic network at speeds up to 20 times faster than Ethernet. The use of fiber optic connections allows the PUC to easily operate in high-noise areas and cover large distances in real time. Adding to the efficiency gains is that the PUC’s knowledge base was sustained, reducing training overhead.

Conclusion

For a utility to be viable in today’s world, the business must use automation platforms to leverage their capabilities. The outcome is lower operating costs, quicker response to changing needs and easier training. By replicating systems faster across the utility, implementation costs are lowered, risk is decreased and completion time is accelerated. Additionally, operators can create solutions without putting added demands on IT. Creating consistency, efficiency and accountability and enabling collaborative information with a holistic approach are keys to success. At that point, utilities can optimize every aspect of water operations for high performance in today’s connected world.