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2020 Eugene Wastewater Master Plan Chapter 1: Introduction and Summary 3 • Chapter 3 also concludes that the City of Eugene has maintained excellent GIS information about the wastewater system, allowing a high level of planning and certainty in the system characteristics and function. • Seismic studies indicate that Eugene’s wastewater system should perform reasonably well in the event of an earthquake. Most of the city’s pump stations are located in non- to low-liquification zones, and less than 1 percent of the gravity wastewater line segments are expected to experience some level of damage. Adherence to seismic standards for pump station construction and continued cured-in-place pipe rehabilitation will further improve the structural integrity of the system. • Chapter 4 notes that sizing a wastewater system without specific development plans or a unified ownership or shared development strategy in the upper reaches of the basin is challenging. The methodology outlined in this chapter is typical of many municipalities and has been successful in the design of much of the Eugene system. Utilizing this methodology when preparing a wastewater study should minimize the need for capacity expansion under normal development conditions. • Private service laterals and private systems and their contribution of inflow and infiltration to the local and regional system are likely to be a growing issue, as discussed in Chapter 5. Further analysis of the problem is needed, and a long-term strategy should be implemented to ensure that system capacity is preserved and regulatory goals eliminating sanitary sewer overflows are met. • As detailed in Chapter 5, nearly 29 percent of Eugene’s wastewater collection system is at least 50 years old and has not been rehabilitated. Studies indicate that 50 years may approach the design life of concrete pipe materials, particularly those installed before advanced gasket technology was available. In addition, the systemwide needs due to future urban development must be considered. • Chapter 5 also recognizes that a significantly increased funding level for rehabilitation over the next 20 years is critical to catch up with the demand of rehabilitating the existing concrete pipe inventory. As of 2019, the total estimated cost to rehabilitate 202 miles of the oldest parts of Eugene’s system exceeded $185 million.