Agenda - Public Works Committee - 02/15/2011

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Public Works Committee Date: 02/15/2011 By: MaryJo Warner Engineering/Public Works Information Title: Overview of the Utility Department SCADA System Item #: 5. 1. Background: The purpose of this case is to provide information on our SCADA system and to provide the Public Works Committee an opportunity to ask questions about our operations. What is SCADA? The acronym SCADA stands for Supervisory Control and Data Acquisition, this is a computerized system that includes radio telemetry, and programmable logic controllers that monitor and control all aspects of the City of Ramsey's utility system. The sites included on the SCADA system are 7 sanitary sewer lift stations, 8 city wells, 4 city well pump houses, 3 water towers, 1 well vault, 1 emergency backup generator and 1 main master PLC/ Computer. We currently have around 600 different alarms that will call our on call person whenever a problem arises. An example of some of the alarms are: • intrusion alarms when unauthorized personal enter our water site • cold temperature • flood alarms • pump failures • power outages • high levels • low levels What is a lift station? A sanitary sewer lift station is constructed when the elevation of a subdivision will not flow into the gravity sanitary sewer system. All the sewer mains are constructed within the subdivision to flow into a large cement holding tank. When flow enters and fills this structure, there are a series of floats that start one or two submersible pumps that push the sewer through a force main uphill sometimes several miles into our gravity system. How and what does the SCADA system do? The SCADA system monitors and controls the city's 25 different sites. Our 8 city wells are controlled by this system by water pressure at the bases of our water towers. It tells the wells when to turn on, how fast to run, how much chemical feed must be injected and when to shut down so the water towers do not overfill. Also our 7 lift stations are monitored and alarm out for issues that typically arise at these sites. They include: • pump failures • high and low levels in the wet well. Most alarms and pump start and stops are controlled by a series of floats that hang in each lift station. Staff will give a live demonstration of the SCADA system and will be available to answer questions.