The Interstate Commission on the Potomac River Basin (ICPRB) is charged with helping to manage the water available to Washington, D.C. and parts of Maryland by monitoring and controlling the water level in the Potomac River. This is managed by releasing or withholding water from several reservoirs that feed the river.

The Potomac Basin stretches across parts of four states (Maryland, Pennsylvania, Virginia, and West Virginia) as well as the District of Columbia. This area is also called the Potomac Watershed. It includes all of the land area where water drains towards the mouth of the Potomac – the point where the river spills into the Chesapeake Bay.

The ICPRB recently embarked on a program to monitor the water level using automated sensors and real-time modem communication. They chose the OTT Nimbus bubbler sensor with Hydras 3 software to accomplish this task. The OTT Nimbus monitors the water level, and Hydras 3 allows the instrument to automatically send an alarm in the form of an email message and pager signal to the project coordinators when the water level rises above or drops below preset limits.

When fully implemented, the combination of several OTT Nimbus units will allow the ICPRB to manage the reservoirs without sending staff into the field, and the system will notify them when river conditions change unexpectedly.