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Teri Higgins June 30, 2016 Page 9 Three potential general vulnerabilities for Eugene pump stations include: 1) power interruption, 2) electrical and control cabinet toppling, and 3) site liquefaction. The general status of items 1) and 3) are shown on Table 6. Regional power interruption is likely. High voltage substations transporting power into the region are vulnerable. Power systems have failed following many earthquakes around the world, and would be expected in a CSZ event. As the entire region could well be without power, two power sources would not improve the power reliability. Electrical power and control cabinets are vulnerable to toppling if they are not properly anchored. During the site visits, observations inside the cabinets were not made. Three of the pump stations are in low liquefaction zones (0‐5% probability). If the liquefaction occurred, the pump station manhole/vault could float damaging both inlet and outlet connecting piping. Pipe is ductile iron so significant differential movement would be required to cause it to fail. A better understanding of the City geotechnical seismic environment should be developed, and critical facilities addressed accordingly. Focused discussions about each pump station that was evaluated follow. Fillmore Pump Station Manhole and vault structures and piping appear adequate to resist seismic loading. Submersible pumps anchorage dependent of manufacturer’s design. Historically these have not failed in earthquakes West Irwin The pump station caisson is divided into wet‐ and dry wells with a reinforced concrete wall separation. The pump station superstructure corners overhang the caisson; it is unclear whether they are cantilevered or on small foundations. If they are supported on foundations, differential settlement could damage the building. The brick superstructure was retrofitted with a steel frame between wall sections and supporting the roof trusses. No retrofit design drawings were available. The superstructure should be evaluated by a structural engineer. The brick walls are rigid and the steel frame is ductile. When subjected to 2 – 3 minutes of shaking, the bricks could fall away leaving no lateral support for the remaining steel columns that support the roof Pump discharge lines and the discharge header lateral support appear to be inadequately braced, and should be checked by a structural engineer. In the event the pump station fails, it is designed to overflow to Terry St Pump Station, so pump station failure may not be catastrophic. 2020 Eugene Wastewater Master Plan Appendix A-9