Water agencies are monitoring a sheen that is floating down the Potomac River, causing a river intake to close.
The Washington Suburban Sanitary Commission said the Potomac Water Filtration Plant has an intake where the plume is expected to reach early Tuesday morning. In an abundance of caution, a boom has been placed in the river to divert water flow away from the intake, and the intake has been closed until the plume passes.
WSSC does not expect any water supply shortage or any bad effects to its drinking water quality.
The origin and makeup of the sheen is unknown, but early testing indicated it could be something similar to a hydraulic fluid or lubricant. It was first spotted near Point of Rocks, Maryland, on Sunday.