The state has ordered a shellfishing ban along the entire Maine coast starting 6 p.m. Saturday.

Heavy rainfall can flood sewers, saturate septic systems and wash other pollutants into rivers and coastal waters, potentially contaminating clams and other shellfish with bacteria.

Flood closures along the coast are common during rainstorms in Maine, but usually are declared after water tests show local contamination. The Department of Marine Resources declared this one ahead of time because of the severity of of the rain forecasts this weekend.