Biological contact process provides secondary treatment for wet weather flows. For years, many wastewater treatment plants protected their secondary treatment processes from washout during high flow wet weather events by sending some of the primary effluent around the secondary treatment process and then blending it with the final effluent. The U.S. Environmental Protection Agency had proposed a draft blending policy to formalize the conditions under which this wet weather strategy would be allowed, but withdrew it last May in response to public and congressional opposition. As a result, some municipalities may face enforcement actions that require them to provide for “full” secondary treatment of all flows – including peak wet weather flows. But the expansions (more primary and secondary treatment capacity, large equalization basins, or ballasted sedimentation processes) needed to handle such flows generally are expensive, especially since they are only used intermittently. Also, biological processes have limited peaking capacity, and many facilities have limited space available. There may be another way. The biological contact process uses bioflocculation to treat wet weather flows. It “borrows” its mixed liquor from the mainstream activated sludge process, allowing rapid startup during wet weather events. It requires few modifications to be retrofitted to existing wastewater treatment facilities. And unlike physical/chemical treatment processes, it can meet secondary treatment requirements for both total suspended solids (TSS) and biochemical oxygen demand (BOD).