Challenge

Proving high quality drinking water for a city of 59,000 people is a challenge in itself.  Retrofitting the controls and instrumentation for six water treatment plants and 13 remote stations, and tying them all together is an even greater challenge.  The City of Meriden, Connecticut, Water Division, was facing this task in April 2001.

• The water plats and remote stations had limited monitorig and and control capabiities. 
• The newer treatment faciities used motor control centers or analog controls, while older treatment plants, remote pump stations, storage tanks, and metering facilities were manually controlled. 
• Operators had to drive to a facility to solve problems. 
• Effluent water quality data from the filters and water usage data had to be collected at each individual plant. 
• Record keeping and daily, weekly, monthly, and yearly reports were prepared manually.

Solution

Control Systems supplied the City of Meriden with a turnkey secure control system using a Honeywell distributed control system and Siemens remote telemetry units.  Siemens provided the design engineering, installation, training, commissioning and service.  Starting in the spring of 2002, Siemens documented the “as-is” wiring of the equipment at all the facilities, and then met with City operations personnel to work out a description of operation for each facility.

While Siemens was building the panels, the project team met with the consulting engineer and the City to agree on standards and conventions for the control system screens with which the operators would interact.  When this phase was completed, the City’s water division personnel and MIS department visited Siemens for a week of training, then returned later for a week of hardware and software Factory Acceptance Testing.

Installation began in June 2003.  Over seven months, each plant was taken off line while the instrumentation and controls were installed and tested, and then placed back online.  Each plant was brought online according to the schedule agreed to by Siemens, the City and the consulting engineer.

Results

The phased start-up of each plant was completed according to schedule in February 2004.  The networked operation of all six water treatment plants using the control system has proven to be a great success. 

Says Dave Lohman, Assistant Director of Water Operations at Meriden, “We’ve seen labor cost savings now that our operators can handle issues that arise at a plant without having to drive to that site.  Being able to monitor operations of all the plants at once reduces the reaction time, and ultimately improves operating efficiency.  It also increases security, and has allowed us to more accurately report water usage and effluent water quality.  Another plus is the fact that we can automatically manage filter run times, producing more product at less cost.”

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