Mayor Luke Ravenstahl today declared a state of emergency as the city prepares for flooding expected to occur on the weekend.
The declaration allows city government to more quickly acquire anything it needs to address floods from expected heavy rain combined with melting of last month's record snowfall.
"We have very real concerns," the mayor said before a meeting this afternoon to plan for the high water. "We are going to experience flooding, there's no doubt."
Mr. Ravenstahl said the declaration was also designed to get residents' attention to the threat.
"People I talk to casually are surprised to hear a flood is coming," he said. "They don't believe it's going to happen."
He said there are no immediate plans to cancel the St. Patrick's Day Parade Downtown on Saturday, noting the event was held in a blizzard in 1993.
The mayor said light rain was expected to start this evening.
Heavier rain is expected between 7 a.m. Friday and 7 a.m. Sunday, with the potential during that time of 2 to 2.5 inches here and in the mountains.
He cautioned that it is still difficult to say when the flooding would begin and when it would be most serious.
But he said the National Weather Service is telling the city that the rivers Downtown are expected to crest Saturday evening at 27 to 32 feet. The latter level would be comparable to the 1996 flood.
At the Point, 25 feet is flood stage; the Mon Wharf parking lot floods at 18 feet.
Mr. Ravenstahl also said forecasters are expecting 65 to 75 percent of the snow in the mountains that feed the rivers will melt this weekend.
A flood watch issued early this morning by the National Weather Service in Pittsburgh for a few eastern counties now has been expanded to include all of southwestern Pennsylvania.
The flood watch is in effect from Thursday evening through Sunday evening.
The watch area extends from Forest, Venango and Mercer counties in the north to Allegheny, Washington and Greene counties. Also included in the watch area are counties in eastern Ohio, northern West Virginia and western Maryland.
A flood watch means there is a potential for flooding based on current forecasts of snow melt and rainfall.
Also, the Pennsylvania Department of Environmental Protection has continued until 10 p.m. Wednesday the air quality alert for southeastern Allegheny County. Included in the alert area are the communities of Clairton, Glassport, Liberty, Lincoln and Port Vue. A buildup of pollutants in the atmosphere means residents with respiratory problems should limit outdoor activities.
The weather service said periods of rain starting Thursday will add to the runoff and increase the risk of flooding for rivers and smaller streams. Widespread rainfall Friday into Saturday will increase the chances of flooding along the Monongahela and Ohio rivers and their tributaries.
Check out the PG's weather page for the latest conditions and forecast. Commuters also can access the updated traffic conditions.
First Published March 10, 2010 11:00 AM