The department of ecology shall work with local governments to develop reasonable plans and compliance schedules for the greatest reasonable reduction of combined sewer overflows. The plan shall address various options, including construction of storage tanks for sewage and separation of sewage and stormwater transport systems. The compliance schedule shall be designed to achieve the greatest reasonable reduction of combined sewer overflows at the earliest possible date. The plans and compliance schedules shall be completed by January 1, 1988. A compliance schedule will be a condition of any waste discharge permit issued or renewed after January 1, 1988.