Early Saturday morning, July 29, more than three inches of rain fell in the Monongahela River watershed.   At the Allegheny County Airport more than an inch fell between midnight and 12:53am where the total was 3.51″ in 24 hours.

Initial flooding occurred along streams and creeks and affected homes and roads, but by the time I visited Duck Hollow at 2:50p Nine Mile Run was back inside its banks while the Monongahela River was rising fast.

My two photos above show where the mudflat used to be at Duck Hollow. In only two hours — 2:50p to 4:45p — the river engulfed all but three trees.  I expect they disappeared later.

To give you an idea of what’s missing, here’s Don Kerr’s photo of the mudflat only 20 days ago, 10 July 2017.  There’s a lot underwater!

After watching the river I walked up the Nine Mile Run Trail and found more evidence of flooding along the creek.  Check the captions for more information.

I was amazed to find four snakes sheltering in this tree above the water. They are wrapped together in coils, two by two, waiting for the water to go down. Probably northern water snakes. (See the comments. I am bad at identifying snakes. I had guessed black rat snakes.)

Inside Frick Park, Nine Mile Run scoured the landscape next to the creek.  Flood debris was chest-high in the lowest lying spots and there was evidence the creek had overrun Commercial Street.

No wonder the Monongahela River is rising!

(photo of the Duck Hollow exposed mudflat by Don Kerr in Duck Hollow Facebook Group. Remaining photos by Kate St. John)