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1904     1912     1914     1932     1935     1945     1947

Graphic of equation from Don G. Friedman's 1975 report to calculate risk.


Baltimore Fire

The type and materials of the constructions in American cities during the 1800’s and early 1900’s posed a constant fire threat. On February 8, 1904, Baltimore suffered one of the worst city fires in US history. The fire devastated an area of 140 acres (56 hectares) destroying 1,500 buildings, 2,500 business, and ultimately spread to 86 blocks in 2 days. It is believed that the fire started in the basement of the Hurst Building, located where the Royal Farms Arena currently stands. As a result of this and other urban fires, city ordinances were enacted and fire mitigation guidelines were implemented by insurance companies throughout the nation. These guidelines became the basis of the first building codes.

Fire damage from the Baltimore Fire 1904 - West from Pratt and Gay Streets.
Baltimore Fire, 1904.
Credit: Maryland Historical Society, public domain

Graphic of equation from Don G. Friedman's 1975 report to calculate risk.


Report of the Flood Commission of Pittsburgh

Report of the Flood Commission of Pitt. Book open to a page with a map folded out..
Detail from the Flood Commission of Pittsburgh report.

Hydraulic engineering achieved significant progress at the turn of the 20th century. The 1912 Flood Commission of Pittsburgh report—an example of the sophistication achieved by engineers of the time—contains the results of a study commission appointed to determine the causes and damages caused by floods in the rivers at Pittsburgh and to recommend measures to avert future damages. The surveys and methodologies to estimate flood damages presented in this report were useful to future flood risk modelers and designers.

Extent of Surveys Map included in the Report of the Flood Commission of Pittsburgh, PA published by the Pittsburgh, Murdoch, Kerr & Company in 1912.
Flood Commission of Pittsburgh map.
Credit: Historic Pittsburgh, public domain

Graphic of equation from Don G. Friedman's 1975 report to calculate risk.
Photograph portrait of Allen Hazen in 1911.
Allen Hazen, 1911.
Credit: New England Water Works Association, public domain


Hazen and Fuller

Historical data is a useful but only partial tool to predict the frequency of future severe events. Allen Hazen  (1869-1930) was the first to overcome this shortcoming using statistical methods to synthetically extend the historical series of river flows. Another landmark application was accomplished by Weston Fuller (1879-1935) who formulated the concept of “return period” to measure the annual probability of occurrence of an event of a given magnitude. Their 1914 groundbreaking papers represent a watershed moment in the history of engineering.

Read the Reports:

Allen Hazen, Storage to be Provided in Impounding Reservoirs for Municipal Water Supply, and Weston Fuller, Flood Flows, in Transactions of the American Society of Civil Engineers, Vol. LXXVII. New York, NY: Murdoch, Kerr & Company, 1914

Graphic of equation from Don G. Friedman's 1975 report to calculate risk.
Arnold Genthe's photograph, looking toward the fire on Sacramento Street, San Francisco Fire Sacramento Street 1906-04-18.
San Francisco Fire, 1906.
Credit: Library of Congress, public domain


Earthquake Damage and Earthquake Insurance

The eminent hydraulic engineer John R. Freeman (1855-1932) was one of the first to give impetus to earthquake engineering research and risk modeling in the United States. In 1932, Freeman published a comprehensive treatise which, among other things, compiled large amounts of earthquake damage data to inform the design of resistant buildings and insurance ratemaking. His book also surveyed secondary hazards, like the great fire triggered by the San Francisco Earthquake of 1906. 

Photograph of John Freeman from Cassier's magazine, 1904.
John Freeman, 1904.
Credit: Cassier's Magazine, public domain



Graphic of equation from Don G. Friedman's 1975 report to calculate risk.


Monroe Calculator - model L-160-X. Monroe Calculating Machine Company, New York, NY U.S.A.: c. 1935 

Monroe Calculator - model L-160-X
Credit: NIST Museum Collection

During World War II, atmospheric scientists and mathematicians developed techniques to predict the behavior of atmospheric variables such as precipitation, temperature, and wind speed. The techniques involved the inversion of large matrices and other lengthy calculations. The people who did the mathematical operations, also known as “computers”, used mechanical calculators—like this Monroe calculator—to conduct these tasks. The computations were laborious and could easily take weeks if not more. The tediousness of the computations hampered the progress of research projects until high-speed computers, such as Whirlwind I at MIT, became available around 1951 and opened a wholly new set of research possibilities.

Graphic of equation from Don G. Friedman's 1975 report to calculate risk.
Photograph of Gilbert White from Gilbert White and the Flood Problem, Natural Hazards Center, University of Colorado.
Gilbert White
Credit: Natural Hazards Center, University of Colorado, used with permission


Human Adjustment to Floods

Gilbert F. White (1911-2006), the father of floodplain management, made profound contributions to the efforts for mitigating the effect of floods in the United States. His landmark 1945 Ph.D. dissertation  challenged  the prevailing views about effective flood mitigation techniques and proposed measures of land use and regulation policies as alternatives to help minimize future damages.

Graphic of equation from Don G. Friedman's 1975 report to calculate risk.


Photo taken from a boat during WWII: Europe: France; "Into the Jaws of Death - U.S. Troops wading through water and Nazi gunfire" Collection: Franklin D. Roosevelt Library Public Domain Photographs, 1882 - 1962
D-Day invasion, June 6, 1944.
Credit: NARA, public domain

Wartime Developments in Applied Climatology

Woodrow C. Jacobs (1908-1990) was a climatologist who made important contributions in times of war and peace. During World War II, he was the head of the Special Studies Research Group of the Army Air Force, and one of his key contributions was his participation in the group that set the date for the D-Day invasion of Normandy in June of 1944. In peacetime, he and Helmut Landsberg, another distinguished climatologist, set the base for natural risk studies in the meteorological sciences.

Wartime Developments in Applied Climatology, 1947, book open.
Detail from Wartime Developments in Applied Climatology.
Credit: American Meteorological Society, used with permission



Created August 10, 2020, Updated July 3, 2023