Heavy rains last night on frozen soil dumped inches of rain on our region. This morning a few low-lying streets along waterways were flooded, but not for long. The gauge peaked at just about 11 feet at just about 11:00 this morning and began to fall after that. Prior to that the creek depth was about one foot deep, typical for winter.
In Carnegie, we always remember the flood from Hurricane Ivan in 2004, and whenever heavy rains start to fall and the creek rises many of us run out to watch it. Because runoff comes from storm drains and runs off of hillsides long after the storm has left the area the creek continues rising after the rain stops, but soon begins to subside.
Chartiers Creek used to flood several times a year until the Fulton Flood Control Project was finished in 1972 which dredged the creek to make it deeper, widened the banks to carry a higher flow and straightened out turns so a raging flood could discharge without backing up or tearing out the banks. You will often see the waters rise during summer storms or spring snowmelt when storm sewers and tributaries are discharging into the creek all at once, and the water rises quickly, but crests before it reaches the top of the banks, then slowly recedes. Only once since then has the creek flooded, during Hurricane Ivan in 2004, but with heavy storms repeatedly moving through it’s time to keep watch.
The beds in the creek from this morning, and from just 10 days ago on January 2 from Carothers Bridge.
The railroad trestle is a landmark. Here it is from today and from last summer. The Flood Control Authority cleared the trees and undergrowth from the creek banks this past autumn. As much as I hate to see it go, in a high water event like this it’s necessary.
And the outflow from Campbell’s Run into Chartiers Creek, just after the Mansfield Bridge in Carnegie.
And from just two months ago in October.
The channel is 18 feet deep and typically the water is about one foot deep, but today the waters were about 11 feet and seemed they were directly under the bridge. Here’s a photo from today, and a photo of the geese in the same spot from October, standing on rocks on the creek bed just below the surface.
Gees from October.
I saw a V of geese flying south at dusk yesterday, kind of late for them but I would guess they were heading for higher ground. Often they know weather changes are coming. The mallards were in their accustomed spot, sort of. They tend to nest near the top of the bank. They weren’t afraid of the current either.
The USGS Gauge
The USGS has a gauge at Hammond Street in Carnegie to measure the height and flow of the creek along with a gauge for rainfall that shows results in real time—pretty much up to the minute. Here are the readings from 11:30 this morning showing depth and discharge, or how much water was flowing how quickly.
Click this link to go to the page and bookmark it as well as sign up for an automated notice via text or e-mail ( http://nwis.waterdata.usgs.gov/pa/nwis/uv/?site_no=03085500&agency_cd=USGS ). If you are in Allegheny County, PA, the county’s Twitter account ( https://twitter.com/Allegheny_Co ) has been up to the minute with reports of flooding and damage in all communities in the county.
Here are a few more photos from this morning.