Septic tanks linked to water pollution in northern California

Underground discharge from septic tanks is having an effect on water quality on the north Californian coastline, scientists claim.

A report by researchers at the California Sea Grant College Program, published in Limnology and Oceanography, found evidence that nitrogen and phosphate has been leaked into coastal waters, causing the growth of algal blooms.

Alexandria Boehm, a professor in the Department of Civil and Environmental Engineering at Stanford University, was quoted by the Humboldt Beacon as saying: "Our project is one of the first in California to show definitively that septic tanks can affect coastal water quality through submarine groundwater discharge."

The researchers claimed that their study ruled out other possible causes of increases in the nutrients, such as polluted creeks and fertiliser usage.

Meanwhile, in the UK, scientists at the University of Essex have designed robotic fish for use in water monitoring in ports.