What they came to find out, however, is that the region's 37 sewage plants are responsible as they pump human waste straight into the bay.

All that bodily pollution is feeding the growth of toxic algae blooms, which feast on feces and urine. It turns out that in order to grow, toxic algae blooms need a steady supply of nutrients, which poop and pee provide. (Related: Toxic algae blooms on the West Coast have been a problem for years, in part due to the Fukushima nuclear disaster in Japan.)

Some eight million people live in the San Francisco Bay Area, which means the bodily waste of eight million humans is constantly being dumped into the area's water supply. This is harmful to the water and sea life that lives in it, creating widespread sea creature death and other problems.

According to David Senn, a senior scientist at the SF Bay Nutrient Management Strategy of the San Francisco Estuary Institute, nutrients "may not have triggered this specific event," referring to the most recent onslaught of toxic algae blooms.

"But they contributed to its size, the amount of the organism, and how long it lasted," he added.