Rainstorms routinely flush toxic chemicals, bacteria and even human feces through San Diego’s streets, canyons and rivers — ultimately polluting bays and beaches.

Those same downpours also regularly burst city stormwater pipes and overwhelm clogged waterways, inundating homes and businesses.

Under San Diego Mayor Kevin Faulconer the city laid out what it would cost to fix the problem — a financial blueprint over two decades for preventing undue flooding and coming into compliance with state mandates under the Clean Water Act.