Copyright © 2018 John F. Oyler
August 16, 2018
McLaughlin Run Flooding
Several of our readers have suggested we write a column on the recent flood, focusing on the community’s efforts in support of its victims. The outpouring of offers to help these folks – with actual labor; financially; and with donations of clothing, household goods, and furniture – is indeed the kind of “good news” story that is far too rare today.
It is instructive to access the Bridgeville Police Department Facebook page; it provides an excellent summary of the many organizations that have pitched in to help out, as well as a reminder of how serious a problem this is.
A lot of old-timers are convinced that this is the worst flood ever; there is lots of evidence to support that opinion. According to the USGS (United States Geological Survey) Bridgeville quadrangle map, the contour line representing elevations 820 feet above sea level crosses Railroad Street about two thirds of the way from Baldwin Street to Station Street. Several videos show flood water up that high; thus 820 feet is a good candidate for flood level for this occurrence.
The FEMA (Federal Emergency Management Agency) Flood Hazard map for Bridgeville anticipates a flood level of 819 feet at the approximate location of the Owls Club increasing to 820 feet at the intersection of Baldwin Street and McLaughlin Run Road. The FEMA projected flooded area and observations of this year’s event are quite similar.
The earliest mention we can find of McLaughlin Run in local newspapers is in association with the 1874 flood. The deluge at that time produced eleven fatalities on McLaughlin Run – Mrs. Stratton and five of her children, and Mr. and Mrs. William McLease and their three children.
This flood was destructive throughout the Chartiers Valley, with two deaths on George’s Run, one on Whiskey Run, and one on Painter’s Run. Newspaper accounts describe houses and stables being washed away as well as all the bridges on the Chartiers Valley Railroad and the Washington Pike.
Baldwin Street made the papers for the first time in July, 1924, when “the upper end of the street was under water, and several cellars in the vicinity were inundated.” This may have been the first flood after Baldwin Street was completed.
In June, 1940, “McLaughlin’s Run rose swiftly and flooded a section of Bridgeville, pouring water into cellars”. The bigger news with this event was the fact that fifty picnickers were marooned in the lodge hall at Paris Lake when Paris Creek rose ten feet after an hour of heavy downpour.
The August 6, 1956 flood was described as “the worst here since 1888”. It caused significant damage throughout the Chartiers Valley. This is the event that was documented by Don Toney in a home movie that has been donated to the Bridgeville Area Historical Society. The newspaper article reports that six feet of water inundated the Flannery Bolt plant, forcing it to shut down. It fails to report Don’s loss of a valuable comic book collection.
A June 25, 1972 newspaper article bears the headline “Flood Controlled in Chartiers” and reports that, thanks to the recent flood control project, “the folks in the Char Valley were high and dry” during a recent storm that produced the third highest flood level in the Ohio River in recorded history. The article did mention that several homes on Baldwin Street had water in their cellars.
During a flood on February 24, 1975, “Water spilled into the basement of the Bridgeville Borough Building”, as well as “homes on Missouri Avenue and Baldwin Street”.
On August 18, 1980, “rampaging water from McLaughlin Run flooded a dozen businesses and approximately sixty homes in Bridgeville”. The borough manager declared this to be the “worst experience in forty years”. The article included a photograph of Baldwin Street resident Edward Cherosky sweeping water away from his home.
Heavy storms in late June and early July, 1981, were described as “hundred-year rains”. Once again it was necessary for folks on Baldwin Street to be evacuated and have water pumped out of their basements. Local citizens complained about a DER (Department of Environmental Regulation) decision against spending five million dollars dredging the McLaughlin Run channel.
The next flood to be severe enough to warrant featuring in the daily papers was August 13, 1984, probably because it jeopardized the resiliency of the Upper St. Clair municipal tennis courts. Baldwin Streeters were reported to be following their normal routine – pumping out their cellars and setting out their destroyed furniture for trash pickup.
A newspaper article in November, 1985, attributed dredging done in McLaughlin Run to preventing flooding after a recent downpour. It quoted Bridgeville Police Chief Leonard Villani. “Basements of several homes in Bridgeville were flooded”.
An article dated August 30, 1990, documented the Borough’s desire to rebuild the Baldwin Street storm sewer system and mentioned a severe flood there on July 12.
Another flood, on September 7, 1990, resulted in a well-attended town meeting at which the Upper St. Clair Planning Director essentially denied any responsibility for the problem, stating the state DER “was satisfied with the progress we’ve made”.
A June 17, 2004, photograph of a Baldwin Street family sorting through items removed from their basement following the Hurricane Ivan flood two days earlier documented the fact that frequent flooding of McLaughlin Run would persist into the twenty-first century.
I am sure there are numerous other mentions of numerous other floods. Suffice it to say, this has been a constant problem for well over fourteen decades, and it appears to be growing more frequent and more severe today.
An experienced hydrologist studying this problem would not be surprised that a significant rainfall intensity, say one inch per hour, would be enough to force McLaughlin Run to overflow. Review of the USGS stream gage at Carnegie suggests that about fifteen percent of the rainfall in the Chartiers Creek watershed eventually reaches Carnegie.
Applying this runoff coefficient to the McLaughlin Run watershed (7.2 square miles) suggests a storm-water rate of about 58 Acre-feet per hour. Assuming a cross-sectional area of 100 square feet for McLaughlin Run and a stream velocity of 3.0 feet per second, the creek can handle about 25 Acre-feet per hour without overflowing.
Assuming a concentration time of one hour for the runoff to reach the Bower Hill Road bridge, it is still obvious that a one inch per hour rainstorm over the whole watershed is sure to produce a flood. The higher intensities reported and the debris choking the creek channel easily explains the large area that was inundated by this event.
It is customary for an engineering evaluation of alternative solutions to a problem to include and evaluate the alternative of doing nothing. Baldwin Street residents have put up with it for over a century with the only consolation being Andy Warhol’s “fifteen minutes of fame” when they are interviewed on the 11:00 News or on the front page of the Pittsburgh newspapers.
Chances are this alternative will be selected, by default, and we will see properties in the flood plain continue to deteriorate until there is no choice but to demolish them and abandon the area.
One of the alternatives currently being considered is precisely that – to abandon everything in the flood plain and convert the area into a detention pond. Suppose everything below the 820-foot contour and west of McLaughlin Run Road was replaced by a basin fifteen feet deep with McLaughlin Run entering it via a series of small waterfalls and then meandering through it.
This would require a rugged wall (dam) along Bower Hill Road and up Jane Way and about 25,000 cubic yards of excavation. However, properly done, the end product could be a very attractive natural park (in between heavy rainstorms).
Some sort of debris prevention would be required for this alternative. Someone has already recommended installation of a trash rack across the valley at the point where McLaughlin Run leaves Upper St. Clair Township and enters Bridgeville, preventing illegal immigration of undesirable Upper St. Clair tree trunks into our borough. Someone else, probably sporting a MAGA ball cap, has expanded this idea by replacing the trash rack with a large dam and an outlet valve to limit flow in the creek.
Most people acknowledge that this is a regional problem involving Bethel Park and Upper St. Clair as well as Bridgeville, with Bridgeville suffering most from its consequences. Channel improvements in Upper St. Clair have succeeded in aggravating the problems in Bridgeville.
Incremental improvements within the Borough’s jurisdiction would serve to reduce the severity of floods slightly. About fifteen percent of the watershed is in Bridgeville; diverting its storm sewer system to the old Chartiers Creek channel would be expensive but helpful. It would also eliminate the frequent problem of the storm sewers backing up and flooding Baldwin Street.
The percentage of rainfall that becomes runoff is several times as high in developed areas as in forested or agricultural ones. The long-term trend toward development continues to make things worse. It is obvious that a proactive campaign to introduce a series of detention ponds along the entire length of McLaughlin Run should be initiated.
We wonder how the storm-water runoff from the hundreds of acres of pavement in the South Hills Village/Village Square complex is handled. If it discharges into Greaser Run, the major tributary of McLaughlin Run, it is easy to understand the destruction of the Outback Restaurant. If that is the case, detention ponds in that area would be quite effective.
At any rate, the first step in resolving this problem is to understand it in detail. It certainly warrants a comprehensive hydrologic analysis of the complete watershed and development of a mathematical model to evaluate any proposed changes.
All this discussion ignores another relevant problem in the watershed – the abandoned mine pollution that enters McLaughlin Run after it is well within Bridgeville’s borders. Its solution is to locate a series of remediation ponds like those at Wingfield Pines, in the old Chartiers Creek bed, and to pump the discharge to them.
In summary, certain things are obvious. Rainstorms of the magnitude of the recent one will occur frequently. Without major changes to the overall watershed the Baldwin Street neighborhood will eventually be degraded to the point of abandonment.
Copyright © 2018 John F. Oyler
August 16, 2018
McLaughlin Run Flooding
Several of our readers have suggested we write a column on the recent flood, focusing on the community’s efforts in support of its victims. The outpouring of offers to help these folks – with actual labor; financially; and with donations of clothing, household goods, and furniture – is indeed the kind of “good news” story that is far too rare today.
It is instructive to access the Bridgeville Police Department Facebook page; it provides an excellent summary of the many organizations that have pitched in to help out, as well as a reminder of how serious a problem this is.
A lot of old-timers are convinced that this is the worst flood ever; there is lots of evidence to support that opinion. According to the USGS (United States Geological Survey) Bridgeville quadrangle map, the contour line representing elevations 820 feet above sea level crosses Railroad Street about two thirds of the way from Baldwin Street to Station Street. Several videos show flood water up that high; thus 820 feet is a good candidate for flood level for this occurrence.
The FEMA (Federal Emergency Management Agency) Flood Hazard map for Bridgeville anticipates a flood level of 819 feet at the approximate location of the Owls Club increasing to 820 feet at the intersection of Baldwin Street and McLaughlin Run Road. The FEMA projected flooded area and observations of this year’s event are quite similar.
The earliest mention we can find of McLaughlin Run in local newspapers is in association with the 1874 flood. The deluge at that time produced eleven fatalities on McLaughlin Run – Mrs. Stratton and five of her children, and Mr. and Mrs. William McLease and their three children.
This flood was destructive throughout the Chartiers Valley, with two deaths on George’s Run, one on Whiskey Run, and one on Painter’s Run. Newspaper accounts describe houses and stables being washed away as well as all the bridges on the Chartiers Valley Railroad and the Washington Pike.
Baldwin Street made the papers for the first time in July, 1924, when “the upper end of the street was under water, and several cellars in the vicinity were inundated.” This may have been the first flood after Baldwin Street was completed.
In June, 1940, “McLaughlin’s Run rose swiftly and flooded a section of Bridgeville, pouring water into cellars”. The bigger news with this event was the fact that fifty picnickers were marooned in the lodge hall at Paris Lake when Paris Creek rose ten feet after an hour of heavy downpour.
The August 6, 1956 flood was described as “the worst here since 1888”. It caused significant damage throughout the Chartiers Valley. This is the event that was documented by Don Toney in a home movie that has been donated to the Bridgeville Area Historical Society. The newspaper article reports that six feet of water inundated the Flannery Bolt plant, forcing it to shut down. It fails to report Don’s loss of a valuable comic book collection.
A June 25, 1972 newspaper article bears the headline “Flood Controlled in Chartiers” and reports that, thanks to the recent flood control project, “the folks in the Char Valley were high and dry” during a recent storm that produced the third highest flood level in the Ohio River in recorded history. The article did mention that several homes on Baldwin Street had water in their cellars.
During a flood on February 24, 1975, “Water spilled into the basement of the Bridgeville Borough Building”, as well as “homes on Missouri Avenue and Baldwin Street”.
On August 18, 1980, “rampaging water from McLaughlin Run flooded a dozen businesses and approximately sixty homes in Bridgeville”. The borough manager declared this to be the “worst experience in forty years”. The article included a photograph of Baldwin Street resident Edward Cherosky sweeping water away from his home.
Heavy storms in late June and early July, 1981, were described as “hundred-year rains”. Once again it was necessary for folks on Baldwin Street to be evacuated and have water pumped out of their basements. Local citizens complained about a DER (Department of Environmental Regulation) decision against spending five million dollars dredging the McLaughlin Run channel.
The next flood to be severe enough to warrant featuring in the daily papers was August 13, 1984, probably because it jeopardized the resiliency of the Upper St. Clair municipal tennis courts. Baldwin Streeters were reported to be following their normal routine – pumping out their cellars and setting out their destroyed furniture for trash pickup.
A newspaper article in November, 1985, attributed dredging done in McLaughlin Run to preventing flooding after a recent downpour. It quoted Bridgeville Police Chief Leonard Villani. “Basements of several homes in Bridgeville were flooded”.
An article dated August 30, 1990, documented the Borough’s desire to rebuild the Baldwin Street storm sewer system and mentioned a severe flood there on July 12.
Another flood, on September 7, 1990, resulted in a well-attended town meeting at which the Upper St. Clair Planning Director essentially denied any responsibility for the problem, stating the state DER “was satisfied with the progress we’ve made”.
A June 17, 2004, photograph of a Baldwin Street family sorting through items removed from their basement following the Hurricane Ivan flood two days earlier documented the fact that frequent flooding of McLaughlin Run would persist into the twenty-first century.
I am sure there are numerous other mentions of numerous other floods. Suffice it to say, this has been a constant problem for well over fourteen decades, and it appears to be growing more frequent and more severe today.
An experienced hydrologist studying this problem would not be surprised that a significant rainfall intensity, say one inch per hour, would be enough to force McLaughlin Run to overflow. Review of the USGS stream gage at Carnegie suggests that about fifteen percent of the rainfall in the Chartiers Creek watershed eventually reaches Carnegie.
Applying this runoff coefficient to the McLaughlin Run watershed (7.2 square miles) suggests a storm-water rate of about 58 Acre-feet per hour. Assuming a cross-sectional area of 100 square feet for McLaughlin Run and a stream velocity of 3.0 feet per second, the creek can handle about 25 Acre-feet per hour without overflowing.
Assuming a concentration time of one hour for the runoff to reach the Bower Hill Road bridge, it is still obvious that a one inch per hour rainstorm over the whole watershed is sure to produce a flood. The higher intensities reported and the debris choking the creek channel easily explains the large area that was inundated by this event.
It is customary for an engineering evaluation of alternative solutions to a problem to include and evaluate the alternative of doing nothing. Baldwin Street residents have put up with it for over a century with the only consolation being Andy Warhol’s “fifteen minutes of fame” when they are interviewed on the 11:00 News or on the front page of the Pittsburgh newspapers.
Chances are this alternative will be selected, by default, and we will see properties in the flood plain continue to deteriorate until there is no choice but to demolish them and abandon the area.
One of the alternatives currently being considered is precisely that – to abandon everything in the flood plain and convert the area into a detention pond. Suppose everything below the 820-foot contour and west of McLaughlin Run Road was replaced by a basin fifteen feet deep with McLaughlin Run entering it via a series of small waterfalls and then meandering through it.
This would require a rugged wall (dam) along Bower Hill Road and up Jane Way and about 25,000 cubic yards of excavation. However, properly done, the end product could be a very attractive natural park (in between heavy rainstorms).
Some sort of debris prevention would be required for this alternative. Someone has already recommended installation of a trash rack across the valley at the point where McLaughlin Run leaves Upper St. Clair Township and enters Bridgeville, preventing illegal immigration of undesirable Upper St. Clair tree trunks into our borough. Someone else, probably sporting a MAGA ball cap, has expanded this idea by replacing the trash rack with a large dam and an outlet valve to limit flow in the creek.
Most people acknowledge that this is a regional problem involving Bethel Park and Upper St. Clair as well as Bridgeville, with Bridgeville suffering most from its consequences. Channel improvements in Upper St. Clair have succeeded in aggravating the problems in Bridgeville.
Incremental improvements within the Borough’s jurisdiction would serve to reduce the severity of floods slightly. About fifteen percent of the watershed is in Bridgeville; diverting its storm sewer system to the old Chartiers Creek channel would be expensive but helpful. It would also eliminate the frequent problem of the storm sewers backing up and flooding Baldwin Street.
The percentage of rainfall that becomes runoff is several times as high in developed areas as in forested or agricultural ones. The long-term trend toward development continues to make things worse. It is obvious that a proactive campaign to introduce a series of detention ponds along the entire length of McLaughlin Run should be initiated.
We wonder how the storm-water runoff from the hundreds of acres of pavement in the South Hills Village/Village Square complex is handled. If it discharges into Greaser Run, the major tributary of McLaughlin Run, it is easy to understand the destruction of the Outback Restaurant. If that is the case, detention ponds in that area would be quite effective.
At any rate, the first step in resolving this problem is to understand it in detail. It certainly warrants a comprehensive hydrologic analysis of the complete watershed and development of a mathematical model to evaluate any proposed changes.
All this discussion ignores another relevant problem in the watershed – the abandoned mine pollution that enters McLaughlin Run after it is well within Bridgeville’s borders. Its solution is to locate a series of remediation ponds like those at Wingfield Pines, in the old Chartiers Creek bed, and to pump the discharge to them.
In summary, certain things are obvious. Rainstorms of the magnitude of the recent one will occur frequently. Without major changes to the overall watershed the Baldwin Street neighborhood will eventually be degraded to the point of abandonment.
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