The 1991 Congress authorized and directed the Pittsburgh District of the U.S. Army Corps of Engineers to undertake a major rehabilitation of the existing Johnstown, Pennsylvania Local Flood Protection Project (LFPP).

The $40 million rehabilitation initiated in 1997 and completed in 2004 will ensure the project’s capability of providing the degree of protection for which it was originally constructed.  The rehabilitation work included repair or replacement of 53 existing wall sections (both federal and non-federal owned, but all part of the project), portions of the slope and channel bottom concrete paving, as well as the resolution of the ownership and repair responsibilities of the privately owned walls.  Critical operations and maintenance work items have also been identified to be completed concurrent with the rehabilitation work, but are subject to receipt of Operations & Maintenance funds. 

There is currently $3 million of maintenance work that is scheduled to be completed in 2008 and 2009.  Operations & Maintenance funded work include repairing and sealing deteriorated concrete slop paving and flood walls, weep hole cleaning, safety hand railing repair and replacement and sediment removal to maintain channel capacity.

In 1998 Congress added $164,000 to the project for construction of the Unit 3 Trail.  The Johnstown Redevelopment Authority has agreed to be the local sponsor and will be responsible for acquiring necessary real estate, 50 percent of the trail cost and future trail operation and maintenance.

Johnstown Flooding and the U.S. Army Corps of Engineers

A LEGACY OF FLOODING

Johnstown, Pennsylvania is the city most closely associated in American history with the tragic consequences of flooding.  Although it was an important center of iron and steel manufacturing from the mid-19th century onward, the city's reputation rests largely on the catastrophic "Johnstown Flood" of May 31, 1889 that claimed the lives of 2,209 individuals and physically devastated the city.  Even before the 1889 flood, however, damaging high water had been a perennial Johnstown problem.  The first flood recorded by white settlers occurred in 1808, and damaging floods followed at least once a decade until the 1880s and in seven of the nine years between 1880 and 1888.  Floods continued to plague the city long after it was rebuilt following the 1889 disaster, with water cresting at flood stage another 21 times between 1889 and 1942.  Significant floods took place in 1894, 1907 and 1924, but the most significant flood prior to 1977 was the St. Patrick's Day Flood of March 1936.

GEOGRAPHY AND RIVER OBSTRUCTIONS

Several factors contribute to Johnstown's flood potential.  The high, steep hills of the narrow Conemaugh Valley and the Allegheny Mountain range to the east have historically forced development close to the riverfronts, and subjected the valley to large amounts of rain and snowfall.  Deforestation, caused by extensive settlement of the area, contributed to rapid runoff problems beginning after the Civil War.  In addition, in-filling for construction, municipal dumping and industrial waste deposits along the rivers have contributed to the restriction of the channel.

EARLY FLOOD RELIEF & CONTROL EFFORTS (1889-1936)

In the wake of the 1889 flood came the first broad based flood control effort in Johnstown.  Acting on a request from Pennsylvania's Governor Beaver, President Benjamin Harrison ordered Army engineer troops from the U.S. Engineer School at Fort Totten, New York, to Johnstown to construct bridges and to assist in organizing debris removal.  The governor also asked for help from the U.S. Army Corps of Engineers to increase the water-carrying capacity of the river channels.  The Corps concurred on the severity of the problem and suggested that the problem be addressed with dredging and water-tight embankments.  The Corps could not undertake such a project, however, as its legal mandate at that time authorized it only to provide navigation improvements, not flood control.

Beginning in 1890, the city of Johnstown initiated a series of actions intended to alleviate flooding.  Ordinances prohibited dumping and other river obstructions and established minimum channel widths.  In addition, flood walls of masonry or concrete were built in selected locations along the rivers during this period.

In response to the 1936 flood, the federal Works Progress Administration (WPA) erected a masonry flood wall just upstream of the Central Avenue Bridge on Stonycreek River and the concrete balustrade wall on top of an existing concrete retaining wall along Roosevelt Boulevard on the left bank of the Conemaugh River.  These structures, as well as 7,889 linear feet of masonry walls and 8,452 linear feet of concrete walls would later be incorporated into the Corps’ Johnstown LFPP.

OVERVIEW OF THE CORPS PROJECT

The Johnstown LFPP is significant as a specialized engineering structure.  Designed and constructed by the Pittsburgh District of the U.S. Army Corps of Engineers between 1938 and 1943, it became the nation's second largest flood control structure of its type and is the largest paved channel project in Pennsylvania.

The project consists of 8.8 miles of stream channel improvements along the Conemaugh, Little Conemaugh and Stonycreek Rivers.  Its construction combined enlarged river channels, paved side-slopes and concrete walls with existing foundations and retaining walls.  Authorized under the 1937 amendments to the Flood Control Act of 1936, it was designed to protect the city of Johnstown from flows equivalent to the level experienced during the infamous St. Patrick's Day Flood of 1936.

Until the "500-year flood" of 1977, which greatly exceeded the project's design capacity, the LFPP provided over five flood-free decades to Johnstown.  It continues to play an important role in community revitalization efforts and remains a significant and prominent feature of the city's landscape.

As a local flood protection project, Johnstown ranks as an impressive national achievement.  Beyond its engineering significance, the Johnstown LFPP recalls the 1930s move toward federal cooperation with state and local governments in the construction and maintenance of local flood protection projects.  It remains one of only a few such projects nationwide to continue under federal ownership.  Johnstown also reflects the determination of a nation struggling to overcome the Great Depression and the memory of Johnstown's 1889 flooding disaster.

THE MARCH 1936 FLOOD

The bleak economic conditions in Depression-era Johnstown were further magnified by the devastating St. Patrick's Day Flood on March 17, 1936.  Three days of heavy rains, combined with run-off from a cold winter's deposits of ice and snow, caused the river to rise 14 feet over the sidewalks in the downtown area within a period of hours.  Nearly one-third of the city was inundated by the waters, which destroyed 77 buildings and damaged thousands more.  Besides the damage to industrial facilities, residential structures, and commercial enterprises, millions of dollars in damage occurred to public facilities such as bridges, sidewalks and roads.  By the time the waters had receded on the evening of the second day, $50 million in damage had been inflicted, 25 people had been killed and 9,000 people were left homeless.

The need for a systematic program of flood control for Johnstown, which had been discussed periodically since 1889, was galvanized by the St. Patrick's Day Flood.  On March 25, 1936, the American Legion post at Johnstown wrote to Senator Joseph Cuffey requesting federal relief for slum clearance and home building, as well as for flood prevention.  Aid in the form of WPA projects was immediately forthcoming for flood clean-up and repairs.  Later, several projects directly related to flood prevention were approved.

THE 1936 FLOOD CONTROL ACT

Congress passed the federal Flood Control Act of 1936 later that year.  The passage of the act authorized the appropriation of federal money for projects whose primary purpose was flood control, and it was a significant development in the effort to secure the political cooperation and money necessary for such an ambitious undertaking in Johnstown.  In response to that effort, President Franklin D. Roosevelt visited Johnstown in August 1936.  Before leaving, the President promised $300,000 for a comprehensive survey to be undertaken by the U.S. Army Corps of Engineers.

The Flood Control Act of 1936 was significant in that it recognized that flood control was a legitimate act of the federal government.  Hundreds of projects constructed under the act would establish the Corps of Engineers as the principal agency overseeing flood control.  However, the act was for a single purpose – flood control – and involved only two agencies – the Corps of Engineers and, to a lesser degree, the Soil Conservation Service.  Multipurpose development of the nation's rivers and true interagency coordination awaited additional legislation.

DESIGN OF THE FLOOD CONTROL PROJECT (1937-1943)

The Johnstown LFPP was among the earliest of the flood control projects undertaken by the Pittsburgh District of the U.S. Army Corps of Engineers under the Flood Control Act of 1936.  It is the longest paved channelization project in Pennsylvania and one of the largest in the United States.  It takes in the most heavily developed stretches of the Little Conemaugh, Stonycreek and Conemaugh Rivers as they flow through Johnstown, including industrial and railroad land, residential areas and commercial districts.

The Pittsburgh District designed the modified river channels to carry peak flows equivalent to those experienced during the St. Patrick's Day Flood of 1936, which are predicted to have a one in 60 chance of occurring in any given year.  By the end of June 1938, detailed surveys and testing had been conducted for the entire project.  Hydraulic model tests at the Corps laboratory in Vicksburg, Mississippi, in which peak flows were tested on a scale model of the project, had shown that the project would perform as designed.

The flood protection improvements consisted of deepening and widening of the channel in all three of Johnstown's rivers, the construction of side-slopes with concrete facing and the construction of concrete flood walls where the channel could not be widened.  Originally, grouted rock paving had been proposed, but it proved too expensive.  As an additional cost-saving measure during the original project construction, some of the existing masonry and concrete walls were incorporated into the structural "line of protection" where feasible.

In addition to the wall and side-slope structures, the Johnstown LFPP also included a small number of channel bottom modifications, including several small spillways and one short stretch of concrete channel bottom lining on either side of the Walnut Street bridge.

CONSTRUCTION CHALLENGES

In order to construct the paved side-slopes, the Corps diverted the flow to the side of the channel opposite the bank under construction.  The concrete paving was laid in slabs, with alternate slabs laid first; the intervening gaps were then filled.  Ramps were constructed for heavy equipment access and for trucks needed to remove excavated material.  Working conditions were difficult in the winter and spring months when snow and ice, then spring run-off, created wet, muddy conditions that tested both men and machines.

THE FINISHED PROJECT

The final cost of the project was $8.87 million, more than $1 million over the original budget.  In all, 2.75 million cubic yards of material were excavated, which if placed in Johnstown's Central Park measuring 240 feet square, it would have made a pile higher than the Empire State Building.  In addition, 156,631 cubic yards of concrete were placed, enough to pave a 20-foot wide road from Johnstown to Pittsburgh, a distance of 67 miles.

The project included modification of 11 bridges; the relocation of two railroads, one highway, one water line and one sanitary sewer; the installation of 17 water line crossings, six sewer line crossings, 14 special drainage outlets and 810 pipe outlets; improvements to 28 culverts, one street and five streams; and the protection of seven houses.  Six vehicle ramps and 55 sets of steps provided access to the channel.

At the project's dedication in November 1943, Pittsburgh District Engineer Colonel Gilbert Van B. Wilkes declared, "Today, Johnstown can boast that it has the largest and best channel improvements in the United States," based on a review of 26 similar projects.  The New York Times reached the same conclusion.  The project was cited as a possible model for other flood control efforts.

"FLOOD-FREE" JOHNSTOWN

In addition to the increased safety and the widespread attention the project brought to Johnstown, completion of the LFPP spurred renewed local interest and confidence in the economic and social revitalization of the city and resulted in the formation of the "Flood-Free Johnstown Observance Committee," a local civic group composed primarily of area businessmen.  The committee enthusiastically embarked on a national campaign to promote the social and business advantages of the city through newspaper articles.  The story reached a nationwide audience estimated at 46 million people.

THE 1977 FLOOD

The LFPP did indeed protect Johnstown from major flooding for several decades.  High water resulting from Hurricane Hazel in 1954 and from Hurricane Agnes in 1972, for example, caused relatively few problems in Johnstown.

The 1977 flood, however, was a massive event that hydrologists predicted had only a one-in-500 chance in happening in any given year.  Swiftly, on the night of July 19, a relentless storm bombarded the city and the rivers began to rise.  By dawn, the city was under water that crested as high as eight feet.  The seven-county disaster area suffered $200 million in property damage and 80 lost lives.  Another 50,000 were rendered homeless.

As the city reeled from the damage, the image of a truly "flood-free Johnstown" was dispelled.  Nonetheless, the LFPP greatly mitigated the effects of the 1977 flood by reducing the flood level in Johnstown by an estimated 11 feet.  The result was a crest six feet lower than that of 1936.  This reduction in flood damage is estimated to have saved $322-332 million.

HOW TO SEE IT

Several vantage points are recommended for viewing the Johnstown LFPP.  An aerial overview is available from the top of the Incline.  The most central location is at the Point.  Other vantage points include the Franklin Street, John Street, Fourth Avenue and Hickory Street bridges, as well as Roosevelt Boulevard at the Cambria Iron Company Nation Historic Landmark footbridge.

The Johnstown LFPP is a historic property eligible for listing on the National Register of Historic Places.  The National Historic Preservation Act requires federal agencies to consider the effect of their actions on historic properties.  To comply with the act, the Pittsburgh District consulted with the Advisory Council on Historic Preservation and the Pennsylvania State Historic Preservation Officer to develop a mitigation plan, which would account for the adverse effects of the rehabilitation to the historic components of the project.  Mitigation features included documentation of the Johnstown LFPP for inclusion in the Department of the Interior's Historic American Engineering Record, interpretive signage for the LFPP in the project area, and a brochure on the project's history.