The City of Portland, Oregon, is developing an integrated maintenance system for its three types of sewer systems, combined, sanitary, and storm. The city of nearly 500,000 has approximately 3,200 kilometers (2,000 miles) of sewers; nearly 30 percent were built in the period 1911 to 1929. Thus, a significant portion of the system will require rehabilitation within a short period of time. The City has recognized the importance of advanced planning and improved maintenance to prolong sewer life. The investment in this integrated management system has been the first step in converting the maintenance budgeting and planning process from a reactive to a proactive mode. The system allows the decision makers to link annual maintenance budget to system performance.