San Diego’s border region is being pummeled every day by massive cross-border flows of sewage-tainted water.

Imperial Beach Mayor Serge Dedina looked at the river flowing through a South County valley on a recent morning.

“This should be dry — dry weather. This should be dry,” Dedina said as he looked at the flowing water. “There should be a pump station on.”

The water flowing in the Tijuana River Valley comes from Mexico and it is on its way to the ocean. On this day, 27 million gallons of sewage-tainted water, which also carries a slurry of toxic chemicals, runs untreated into the United States.