An early morning storm dumped at least three inches of rain on our region and many low-lying roads were inundated and are closed already while more heavy storms are on their way. Above, the geese are concerned because their nests along the creek bank are under water; most of their babies are nearly as large as their parents so hopefully none were caught in the flash flooding as the creek rose.
In Carnegie, we still 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 continued rising until about 10:00 a.m. then crested and began to fall.
Below is what the creek looks like normally in photos I took in June along with photos from this morning about 10:30 a.m. The fishing spot—check where the smaller outflow pipe is on the left in both photos:
View from Hammond Street Bridge—note in the bottom photo from June, near the bottom of the photo, a horizontal line in the water in the creek. This is the weir that corresponds to the USGS gauge mentioned below, while the building that houses the gauge and transmits the data is the small pale structure you see about half-way down the left side of the photo:
I’m pretty fearless around Chartiers Creek, but these raging waters are nothing to fool with. Not only is the current strong and unpredictable, but the water is full of floating debris from basketballs to tree trunks. In addition to the dangers of the rushing water, are the dangers of contamination from runoff from streets as well as the part none of us likes to think about—overflow from our combined street and sanitary sewers. Don’t toss a canoe in and have a ride, it’s far too dangerous.
The USGS Gauge
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 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 is a screen shot of what it looks like at 2:00 p.m. Wednesday. You can see how precipitously the water rose at certain points, coordinating with the rainfall.
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 ).
Communities along Robinson Run—Collier Township, Sturgeon, Oakdale, McDonald as well as others—need to be especially careful as the stream has been overflowing as the streets discharge into it. Oakdale was reported to have four feet of water on the streets with many flooded basements, and Collier Township has reports of washed out or collapsing roadways along ravines and ridges. The community of North Fayette has declared a disaster emergency from excessive flooding and flood damage and many communities have roads closed due to flooded or damaged roads and structures. 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.
More storms are on their way, predicted to drop another two inches this afternoon and again tonight as a cold front comes through. Until it’s over, be aware of the dangers of flooding as well as landslides and falling trees from rain and saturated soil, and possible lengthy power outages. Make sure you have an evacuation and communication plan with family or friends preparing for potentially three days or more without power or completely evacuating, and make sure that includes any pets in your household; for more information on how to prepare for an emergency with your pets, please read “Emergency Preparedness for You and Your Pets” on The Creative Cat.
As I was photographing this morning the geese were trying to get to safety, so Mark Cantley and I helped them cross the street—he parked his truck to block traffic from one directly and I stepped out to block it from the other and we both herded the geese across Main Street. See the post here.