PORTLAND — The Portland Water District and Saint Joseph’s College are hoping their new partnership will help detect the presence of the coronavirus virus in certain areas days earlier than waiting for individual patients’ test results.

Over the next three months, the water district will be sampling wastewater from treatment plants on the East End and on Park Road in Westbrook and sending the samples for testing at the college in Standish.

Scott Firmin, director of wastewater services for the water district, said the tests can give a sense of how quickly, and where, the coronavirus virus is spreading. The tests can detect the presence of the virus six to seven days earlier than individual clinical tests can be added to official case counts.

“People who are infected with COVID-19 will shed the virus,” he said, often before they feel any symptoms. “Wastewater samples provide statistical estimates of infection rates in the city.”