Many car wash facilities are now required by law to treat and reuse their water , while driveway wash water simply ends up in the storm drain and eventually into rivers and lakes . Most car wash facilities are required by law to treat and\/or reuse their water and may be required to maintain waste-water discharge permits , in contrast to unregulated facilities or even driveway washing , where waste-water can end up in the storm drain and , eventually , in streams , rivers and lakes .