Cobbs Creek Reservoir Instrumentation and Monitoring

Cobbs Creek Reservoir in Cumberland County, Virginia, is a $280 million project designed to secure drinking water for Henrico County for decades. It is a 14.8-billion-gallon regional water supply that will help augment the James River's flow during dry periods and store water during wetter months. 
 

Challenge

This project included the construction of the three earthen dams, a water intake structure in the James River, a pumping station, and other facilities. With the construction of a new earthen embankment dam, it was critical for the project team to install a Dam Instrumentation and Monitoring System (DIMS) to monitor the dam performance over its lifetime.
 

Solution

GZA was retained by MEB General Contracts for furnish and install the Dam Instrumentation & Monitoring System (DIMS) and the first Fiber Optic Distributed Temperature System (FODTS) on an earthen dam within the United States. GZA proposed to install a fully automated monitoring system that was locally connected and remotely accessible to the county engineers. Each data transmission point connected to the main inlet outlet tower through secure radio connection. The DIMS included vibrating wire piezometers and vibrating wire weir monitors. 
 

Benefit

GZA’s instrumentation team was able to install the system so all data will be locally hosted and viewable on the County’s network and reviewed by engineers during normal operation. The automated system allows the owners to establish threshold and limiting alarms to automatically notify them of any abnormal changes in the data.