As part of their ongoing SSO management program, the city of Oakland Public Works department needed to measure full depth in a manhole. They had been using monitors with float alarms at fixed heights but found these required a significant amount of time for maintenance.
Five years ago, Oakland began a pilot project using ECHO™ narrow-beam ultrasonic depth monitors from ADS Environmental Services®. ECHO is a next-generation, ultrasonic monitoring system that uses patented “narrow-beam” technology. Unlike conventional ultrasonic sensors, which must be suspended on a flexible cable to within a few feet of the invert flows, ECHO is installed at the top of the manhole.
The ECHO’s narrow-beam technology gives it a full 20-feet of dynamic measurement range. Moreover, its stabilized mounting means that there is no sensor movement as occurs with cable-type ultrasonic sensors, which are prone to movement and can cause false alarms. The ECHO monitors also feature both low and high flow alarms. These configurable alarms can be adapted to the exact requirements for a given manhole.
Thus far, Oakland has expanded the ECHO monitor deployment to include 45 sites, and to take advantage of ADS’ comprehensive services, termed D-SiTE, thereby relieving the City of any maintenance requirements. For a single, monthly subscription fee, D-Site covers the level monitor, installation, configuration, maintenance and 24/7 online data delivery – including alarms and early alerts regarding any emerging issues.
By using a proven turn-key service for monitoring and managing their sewer system, the city of Oakland has been able to both improve their ability to avoid SSOs and reduce their overall costs. The D-Site approach relieves internal staff from the hassles of hardware installation, maintenance and monitoring while assuring they have a continuous 24/7 stream of comprehensive data for alerts, alarms and long-term analysis.