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World War II's Effect on Grease Interceptors

As the United States came out of the Great Depression in the late 1930’s it was in fact the war raging in Europe that provided an almost overnight recovery. Despite resistance, President Franklin Roosevelt's Lend-Lease Act, which was passed by Congress in March 1941, committed America’s vast resources to the war effort against the Axis Powers (Germany, Italy and Japan). Roosevelt aimed to make America the “great arsenal of democracy,” and America was definitely on board.

Consider the staggering amount of money the US spent during the war and the stunning production of US industry to support the war effort:

Shortages and Rationing

When you consider how vast the war effort was and the extremely high demand for raw materials, it may have been fortuitous that the Great Depression took place prior to the US’ entry into WW2. It was during the depression that Americans learned what it meant to make do with less. Shortages and rationing soon became the essential sacrifice of American families in order to ensure that the needs of the “great arsenal of democracy” were met. 

Sugar was the first food to be rationed beginning in the spring of 1942. Japan had cut off US imports from Southeast Asia and the Pacific Islands and cargo ships from Hawaii were diverted for military purposes reducing the nation’s supply of sugar by more than one third. Other shortages included fats and oils, which were also imported from these areas. Meanwhile, demand for fats and oils were ever increasing for military and industrial uses. By March 1943 the Office of Price Administration added butter, fats and oils to rationing. Thus the Fat Salvage Campaign was born, run by the US Department of Agriculture and the American Fat Salvage Committee. Unlike rationing, this program was focused on recycling used cooking fats and grease. 

Housewives to the Rescue A common method of creating soap was to combine fats with lye. The soap making process created a byproduct called glycerin, which was in high demand even before the war in manufacturing food, paints, textiles, medicines and more. One of the needs for glycerin was in making explosives. Much of the propaganda produced by the Fat Salvage Campaign was focused on getting housewives across the country to save their waste fats and grease to be turned into their meat dealer where they would not only be paid for it (around $0.04 per pound) but they could feel good about helping our fighting men win the war. 

But waste fats were of far greater need than just making gun powder and explosives. They were needed to replace the once imported fats and oils in order to keep American plants turning out synthetic rubber, pharmaceuticals, fabrics, military and civilian soaps, lubricating fluids, paints and thousands of other products.

The US Army Discovers a Problem on their End Dealing with the shortages and the need for recycling waste cooking grease wasn’t just the job of American housewives; it was everyone’s job, and the US Military was no exception. Capturing the greasy waste from Army camp kitchens was thought to be sufficiently handled by the specifications for grease interceptors of the Construction Division, Office of the Quartermaster General. Inadequate specifications and the fact that each manufacturer rated their own devices made it clear that a comprehensive engineering and testing program was required in order to properly test and rate grease interceptors.

The Iowa Institute of Hydraulic Research to the Rescue In 1929 the Army Corps of Engineers had established a sub-office at the University of Iowa, which had been developing perhaps the most beneficial hydraulics research laboratory in the nation on the banks of the Iowa River. The Corps was using the lab for its research into dams, spillways, locks and navigation problems. The success of the lab and the desire for the University to bring to bear its full scientific capabilities on hydraulic problems led to the formation of the Iowa Institute of Hydraulic Research in 1931. 

By 1936 Frank Dawson became Dean of the Engineering College and Director of the Institute. Following Dean Dawson’s arrival, the Institute was named the National Laboratory for the Master Plumbers Association. The institutes reputation in fluid hydraulics research and its close working relationship with the military made it the natural choice for a series of conferences involving the Army Corps of Engineers, representatives of the Quartermaster General, the Surgeon General, the Research Committee for the Plumbing and Drainage Manufacturer’s Association, along with Institute staff and others, to develop a testing and rating program for grease interceptors. The aim was to create a uniform testing and rating protocol that would establish flow rates and grease storage capacities for interceptors manufactured at that time. 

The work of the committee was documented by Dean Dawson and Professor Anton Kalinske in a Symposium on Grease Removal, Design and Operation of Grease Interceptors, presented at the Sixteenth Annual Meeting of the New York State Sewage Works Association in New York City on January 21, 1944. The Symposium described the research efforts and the criteria that was established for the performance of grease interceptors. The success of the project led to a mandatory military requirement that any type of interceptor, before it could be installed in an Army camp kitchen, had to have a rating certificate from the Institute.

A Commercial Testing and Rating Standard is Born Quoting from the forward in PDI G101, “Using the guidelines established at the Institute, the Research Committee for the Plumbing and Drainage Manufacturer’s Association continued the testing program at the Unites States Testing Company, Inc., which culminated in the publication of Standard PDI G101 in 1949.” This standard governed commercial grease interceptors and later became the basic testing and rating requirement of Military Specification MIL-T-18361 (revoked without replacement in 1982).

Everything has a beginning including the testing and rating of grease interceptors. Who knows when a standardized and uniform testing and rating protocol would have been developed if it had not been for the shortages, rationing and the incredible mass production of the “great arsenal of democracy” unleashed during World War 2.

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