Widespread flooding continues as near-record rainfall drenches region

The remnants of Tropical Storm Gordon dumped nearly 5 inches of rain over the weekend, making it the second largest amount of rain to fall in a two-day period since the tail end of Hurricane Ivan passed through the region in 2004.

The 4.75 inches of rain that fell this weekend — 1.02 inches on Saturday and 3.73 inches on Sunday — gorged local waterways, downed trees and flooded roads and basements.

As of 5 a.m. this morning an additonal 0.26 inches of rain has fallen with an additional 0.25 inches possible through 8 p.m., according to meteorologist Rich Redmond of the National Weather Service in Pittsburgh.

The most rainfall in the region was recorded on Sept. 17, 2014, when 5.96 inches of rain fell in a 24-hour period, Redmond said.

This weekend's storms also pushed Pittsburgh past its average annual rainfall level. So far this year, 40.9 inches if rain has fallen, according to the weather service.

The average for the year is 38.19 inches.

Allegheny and Westmoreland counties remain under a flash flood warning until 9 a.m. this morning.

The entire region remains under a flood watch until Tuesday afternoon.

Redmond said the combination of last week's warm, dry weather and the heavy rain falling over a two-day period reduced potential problems.

"A lot of the rain had a chance to soak into the ground," he said. "There was still widespread flooding, but if this rain had fallen in a shorter period of time the damage caused could have been much worse."

Etna officials announced Monday night that Little Pine Creek had risen to 13 feet, reaching the underneath of Crescent Avenue bridge.

At 14 feet, it would overflow into low-lying areas.

Residents were being encouraged to tune in to 1670 AM for updates and for information regarding flooded roadways.

The Millvale Borough Public Works Department, with assistance from Allegheny County Emergency Services, is supplying materials under Millvale's 40th Street Bridge for people to build their own sand bags for use should flooding occur, said Maria Christina, North Hills Community Outreach.

Flood warnings remain in effect for the Monongahela River near Elizabeth and Braddock and the Ohio River in Pittsburgh, according to the NWS forecast. The Mononghela River near Braddock was at just over 12 feet at 5 p.m. Sunday, and it was expected to crest the flood stage – 22 feet – by Monday morning.

The Ohio River was at about 18 feet at 5 p.m. Sunday, according to the forecast.

The river floods at 25 feet, which is expected to reach by Monday evening, according to the weather service.

Flooding plagued the usual places in Allegheny County – the 10th Street Bypass and the Mon Wharf in Downtown Pittsburgh remain closed – and shut down dozens of other roads across the county with either flood waters or downed trees.

Officials in White Oak issued a disaster declaration after sewage began backing up into homes in the borough, according to county officials. The disaster declaration was issued to sanitary sewers could be pumped out.

In Westmoreland County, one person had to be rescued from flood waters on Oak Creek Road in Sewickley Township. An emergency dispatcher said the vehicle became trapped in standing water. No one was injured.

State roads that are closed

As of 8:15 p.m. Sunday, these state roads remain closed or restricted because of flooding, downed trees and/or downed utility lines:

Allegheny County

O'Hara: Freeport Road, between Powers Run Road and Boyd Avenue;

South Park Township: Stewart Road/Berryman Avenue, between Brownsville Road and Stoltz Road;

South Fayette: Boyce Road, between Hunting Ridge Road and Washington Road (Route 19)

Westmoreland County

Murrysville police this morning reported that the following streets are closed due to flooding: Ashbaugh Road between Mamont Road, Steele Road between Mamont and Hilty road, Borland Farm Road and Gun Club Road.

A high water alert also was issued for Sardis Road at Crowfoot Road.

Other roads affected in Westmoreland include:

Pine Run Road, Lowber Road, Two Mile Road, Washington Road, Bairdstown Road, Hannastown Road, Route 982, Parkhill Road, Waltz Mill, Route 381 (two locations), St. James Church Road, Hilton Road, Ruffsdale Road, Ross Park Mountain Road, Waltz Mill Road to the Interstate 70 ramp, Route 819, Stone Church to Wicky Lane.

Fayette County

Nelson Road, where there are three bridge closures. Burke Road must be used to access certain areas; Wharton Furnace Road, Eighty Acres Road, Arch Bridge Road, Wharton-Elliottsville Road, Hopwood-Fairchance Road (two locations), Redstone Furnace Road.

“Low spots have taken on water and we expect more road closures through the afternoon,” the National Weather Service in Pittsburgh tweeted.

It reported that 3 inches of rain had fallen by 1 p.m.

Numerous roads were reported closed, at least temporarily, in Allegheny County. Among them:

• The 10 ^th Street Bypass in downtown Pittsburgh, between I-279 Parkway North/Fort Duquesne Bridge and Fort Duquesne Boulevard, as well as the ramps from northbound and southbound I-2 Motorists should use Fort Duquesne Boulevard to detour around the closure. Motorists on I-279 should use the ramps to Fort Duquesne Boulevard.
• North Braddock: Route 30 (one lane blocked by a large rock).
• Franklin Park: 2400 block of Camp Meeting Road;

• Jefferson Hills: Coal Valley Road, between Route 837 and Route 885;

• McKeesport: West Fifth Avenue;

• West Deer: Kaufman Road at Saxonburg Boulevard; Millerstown-Culmerville Road at Tarentum-Culmerville Road;
• Bethel Park: 5700 block of Valleyview Drive; Horning at Englert Farms Road (washed out);
• Baldwin: 3900 block of Churchview (landslide);

• South Park: Stewart Road/Berryman Avenue between Brownsville Road and Brandis Avenue;

• Pittsburgh: Becks Run Road between Brownsville Road and Agnew;
• McCandless: Blazier Drive;

• The Mon Wharf remains closed through at least Monday.

Areas of Fox Chapel and Aspinwall began experiencing localized flooding around 12:45 p.m., and a small but passable landslide was reported on Coketown Road in Robinson, according to the Allegheny County Twitter account.

The weather forced cancellations across the region as well. The Pirates 1:35 p.m. game against the Miami Marlins was moved to Oct. 1, and both Kennywood and Idlewild shut down for the day. Pittsburgh's Irish festival also canceled its final day of festivities.

Tony LaRussa is a Tribune-Review staff writer. You can contact Tony at 724-772-6368 or tlarussa@tribweb.com or via Twitter @TonyLaRussaTrib. Megan Guza is a Tribune-Review staff writer. You can contact Megan at 412-380-8519, mguza@tribweb.com or via Twitter @meganguzaTrib.