7:45pm: A clarification is in order. The mandatory evacuation order is only for the village of Downsville -- particularly for parts of Downsville that are prone to flooding.
An astute reader wonders whether everyone in Downsville must leave, or only people in low-lying areas. The emergency responder I spoke to tonight who answered the phone at the Fire Department said that everyone in the village is being advised to leave. (I didn't catch his name before he had to take another call.)
According to NY-Alert, however, only people in low-lying areas are being told that they should leave. Here's the alert, released at 7pm:
The Pepacton reservoir will begin flooding to moderate flood stage in the Monday morning to afternoon hours in the Downsville area. Residents in the usually flood prone and low lying areas should monitor the situation and be prepared evacuate. A shelter is being established at the Downsville Central School.
7:05pm: I just spoke with an emergency responder at the Downsville Volunteer Fire Department, who confirmed that the village of Downsville is being mandatory evacuated today. Everyone is asked to be out of town by midnight tonight:
"We want everybody out by midnight. [The East Branch of the Delaware River at the Pepacton Reservoir dam] is starting to spill right now, and by tomorrow morning or afternoon it will be at high flood stage."
Here's the hydrograph of the East Branch of the Delaware River at the Pepacton Reservoir:
