Nov 21, 2011

Wireless Alarm System for Wastewater Monitoring

Alarm system bolsters existing SCADA network, preventing unnoticed outages

Amherst is a city of about 37,000 situated in the hills of western Massachusetts. Population growth in the area has been steady over the years, almost doubling since 1960.

With the continuous expansion of three college campuses—the University of Massachusetts at Amherst, Hampshire College and Amherst College—the infrastructure has grown as well. Jim Laford, division supervisor of Amherst’s wastewater division, has witnessed that growth firsthand. His team is responsible for the integrity and reliability of the entire wastewater system.

Backups and power outages at individual lift stations occur periodically, and a reliable, responsive alarm system is critical to ensure that those problems are remedied in a timely manner. This has been a constant challenge throughout the years.

Advances in Technology

Laford has witnessed decades of technological evolution throughout his years with Amherst’s public works department. It started with offline local alarms in the 1970s, phone lines with dial-up alarms in the 1980s and, most recently, a radio telemetry alarm system that transmitted from lift stations to the main treatment plant.

Radio telemetry might be effective in the plains of Nebraska or Kansas, but in the rugged landscape of the Pioneer Valley of Massachusetts, line-of-site radio signals were problematic. Alarm signals had mixed success getting past the hills dotting the countryside.

Repeaters were eventually added to boost system reach, but high-rise dormitory construction created even greater barriers to radio signals. The wastewater district decided to scrap the system and replace it with something that addressed the unique topographical challenges.

A Fresh Start

RACO Mfg. and Eng. Co. offered a proposal centered around to address many of the dilemmas confronting Amherst, including the ability to reliably transmit alarm signals from lift stations to the treatment plant. Many of these unmanned stations were situated in remote locations where landlines were cost-prohibitive, so a wireless autodialer made a lot of sense. RACO was awarded the contract and soon went to work implementing the system.

Upon completion, a wireless alarm network linked 20 lift stations with the main treatment plant. Since Amherst’s wastewater infrastructure was operated and monitored by a SCADA system, an additional autodialer alarm package was installed to monitor the dedicated phone line for SCADA system’s software-based alarm notification system. If the SCADA system went down, the entire wastewater system would be jeopardized.

Without the wireless alarm system, an outage might not be discovered for hours. In wastewater management, no system is too reliable.

More Responsive, More Proactive

The wireless alarm system has protected the Amherst wastewater division for a year and a half. According to Laford, it is the best system to date. False alarms have been eliminated and response time for actual alarms has improved dramatically.

One of the most significant features of the new system contributes directly to diagnostics and preventative maintenance. Personnel can access detailed reports on pump performance across all 20 lift stations by logging into the system's online interface.

These reports include information on pump flow, hours of pump operation and pump alternation. The data enables personnel to address potential problems before they become alarm events. This level of real-time system diagnostics was inconceivable in the past.

Customer satisfaction in Amherst is up, and man hours are down. The city, especially the college campuses, continues to grow, putting increased demands on system capacity, but Laford and his colleagues are confident that they found the right partner in RACO, and the right solution with

James Brown is vice president of sales and marketing for RACO Mfg. and Eng. Co. Brown can be reached at [email protected] or 800.722.6999.

RACO Mfg. and Eng. Co. Inc.


1400 62nd Street

Emeryville, CA 94608

United States

Phone: 800.722.6999

Phone (Toll - Free): 800.722.6999

Fax: 510.658.3153

[email protected]