I knew it had been raining since yesterday, but was the bridge (that I normally drove across to work) closed?I opened my e-mail, and found a message, sent by Somerset County, New Jersey early this morning at 5:03 AM, notifying me that the bridge had been closed. Per suggestion of Mr. Carl Andreassen, the Principal Hydraulic Engineer for the County, I signed up for this
e-mail notification service about a month ago, and this is the first flood-related notification that I received.
Whenever the river level/stage rises up to seven (7) feet, the action stage, the police will be dispatched by the emergency services to close the bridge. The flood stage at this location is nine (9) ft. That is, the bridge will not actually be flooded until the water level reaches 9 ft. There is a stream gauge located close to the bridge; its measured water level is transmitted to the Somerset County Flood Information System via a satellite transmitter as well as a phone line, as a direct connection. The stream gauge is operated by the U.S. Geological Survey. See the picture for the actually measured water level, as indicated by the blue line.
The National Weather Service (NWS)'s Middle Atlantic River Forecast Center, via NWS' Advanced Hydrologic Prediction Service (AHPS), go further to project what the water level might actually approach. See the picture for the predicted water level, as indicate by the dotted green line.
According to the NWS' AHPS prediction, the bridge would remain closed through the evening during my commute home. Of course, I can check the actually measured water level right before I leave my office. I can also assume the bridge would remain closed until a further e-mail notice, a bridge re-opening notice, from Somerset County.
It is nice to live in the information age!
Credit: The image above was made from the NWS's MARFC website.
My presentation contains additional info on flood forecast and warning as well as other aspects of urban flood management.
