July 26, 1930: Death of Allen Hazen. “Allen Hazen (1869–1930) was an expert in hydraulics, flood control, water purification and sewage treatment. His career extended from 1888 to 1930 and he is, perhaps, best known for his contributions to hydraulics with the Hazen-Williams equation. Hazen published some of the seminal works on sedimentation and filtration. He was President of the New England Water Works Association and Vice President of the American Society of Civil Engineers.
During a year spent at MIT (1887-8), Hazen studied chemistry and came into contact with Professor William T. Sedgwick, Dr. Thomas M. Drown and fellow students George W. Fuller and George C. Whipple. As a direct result of his association with Dr. Thomas M. Drown, Hazen was offered his first job at the Lawrence Experiment Station in Lawrence, Massachusetts. LES was likely the first institute in the world devoted solely to investigations of water purification and sewage treatment. From 1888 to 1893, Hazen headed the research team at this innovative research institute into water purification and sewage treatment.
Hazen is most widely known for developing in 1902 with Gardner S. Williams the Hazen-Williams equation which described the flow of water in pipelines. In 1905, the two engineers published an influential book, which contained solutions to the Hazen-Williams equation for pipes of widely varying diameters. The equation uses an empirically derived constant for the “roughness” of the pipe walls which became known as the Hazen-Williams coefficient.
In 1908, Hazen was appointed by President Theodore Roosevelt to a panel of expert engineers to inspect the construction progress on the Panama Canal with President-Elect William H. Taft. Hazen specifically reported on the soundness of the Gatun Dam (an integral structure in the canal system), which he said was constructed of the proper materials and not in any danger of failure.
Hazen’s early work at the Lawrence Experiment Station established some of the basic parameters for the design of slow sand filters. One of his greatest contributions to filtration technology was the derivation of two terms for describing the size distribution of filter media: effective size and uniformity coefficient. These two parameters are used today to specify the size of filter materials for water purification applications. His first book, The Filtration of Public Water Supplies, which was published in 1895, is still considered a classic.
His first assignment as a sole practitioner in 1897 was the design of the filtration plant at Albany, New York. The plant was the first continuously operated slow sand filter plant in the U.S.
One of his early assignments was as consultant to Pittsburgh, Pennsylvania, to determine the best method of providing a safe water supply from the Monongahela River. For decades, the City had been wracked with typhoid fever epidemics. At the time, mechanical filtration (or rapid sand filtration was just beginning to be understood as a treatment process. As a conservative engineer, Hazen recommended that the City install slow sand filters to remove both turbidity and harmful bacteria from its water supply. As early as 1904, Hazen recommended the filtration of the Croton water supply for New York City. As of 2013, a new filtration plant on that water supply is nearing completion.
Hazen received honorary degrees of Doctor of Science from both New Hampshire College of Agriculture and Mechanical Arts (1913) and Dartmouth College (1917). In 1915, he received the Norman Medal which is the highest honor given by the American Society of Civil Engineers for a technical paper that “makes a definitive contribution to engineering science.” He was selected as an Honorary Member of the American Water Works Association in 1930. In 1971, he was inducted into the AWWA Water Industry Hall of Fame with his friend and colleague, George W. Fuller.”
Commentary: This entry is part of the biographical entry for Hazen in Wikipedia that I wrote in June 2012. I did not know much about him until I wrote the article. He was truly an amazing engineer who excelled at everything that he was engaged in.