Perhaps you’ve been out for a stroll across one of the many docks and shipyards that make up the three U.S. Navy bases on the San Diego Bay in San Diego, Calif. Spotting a storm cloud on the horizon, maybe you’ve even thought to yourself, ‘I wonder what could be done to prevent the contamination of marine habitats when surges of storm water flood across industrial facilities that contain potential contaminants like copper and zinc?’
Okay…maybe not, but there is someone who has: Leonard “Len” Sinfield. Not only has this question kept him up at night, Len has invented a filtering device that he hopes will reduce the amount of potential contaminants that run off from industrial sites.
Len, an environmental physical scientist by trade, works as the environmental compliance program manager at Naval Support Activity Souda Bay. Prior to joining NSA Souda Bay in June 2021, Len worked as the Environmental Water Program Manager at Navy Region Southwest in San Diego.
“Storm water pollution was a huge concern at the Navy bases in San Diego under the strict regulation of state environmental protection laws,” explained Len. “When we have a storm event—during that first flush of storm water that comes through—we have to sample the drain water coming out of the pipe that runs into the Bay and test it for toxicity.”
Copper, Zinc and other hard metals—common elements found in a variety products, such as brake pads, paints and petroleum-based fluids—are potentially toxic to marine life. Around industrial areas they collect on parking lots and access roads. Whenever there is a storm event, these elements are washed into storm drains, which drain directly into the nearest watershed. In high enough concentration, these elements are harmful to marine habitats.
“We don’t want to kill the little fishies,” said Len.
When Len had an idea about how to reduce the potential contaminants in industrial runoff and achieve compliance with local laws, the Navy was interested.
“For years we have been trying to solve this storm water issue,” said Len. “I put this storm water filter concept forward through the Navy Environmental Sustainability Development to Integration program before I left San Diego in 2018.”
NESDI is a Navy program that seeks to develop solutions to environmental problems to minimize environmental risks that could potentially impact Fleet readiness.
Len explained that his idea is actually quite simple: Instead of thinking of a single filtration point that the storm water must pass through — like water passing through a coffee filter — think of a filter as something that water must pass alongside as it makes its entire journey through a long drain pipe and out into the watershed (see fig. 1). Len’s invention is best pictured as intermittent filter stages that are placed inside the storm water drain pipe throughout its entire length (see fig. 3). Sort of like many small pipes placed within the large storm water pipe (see fig. 2). Although the contact time between the storm water and each individual filter stage is relatively small, after passing through many of these filter stages on its long journey to the watershed, the contact time with all the combined filter stages is adequate to remove harmful contaminants.
“After working in storm water compliance for about 15 years and seeing the same issues over and over again, the idea was the result of a long term mental siege,” said Len. “No instant flash of genius here. It was like Edison testing a thousand different filaments before finding the right one for the light bulb.”
With the support of the Naval Information Warfare Center Pacific, Len’s innovative idea was awarded a patent through the U.S. Navy patent office in Oct. 2022.
“The U.S. Navy will receive the royalties attached with the patent until they have recuperated their costs,” said Len. “I doubt I’ll ever see anything from it, but even if it’s just a dollar, it would be a cool thing to have framed on my wall!”
NSA Souda Bay is an operational ashore installation which enables and supports U.S., Allied, Coalition, and Partner nation forces to preserve security and stability in the European, African, and Central Command areas of responsibility. For more information, find us on Facebook at www.facebook.com/NSASoudaBay.