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10.6 Other Earthquake Loss Estimates and Comments for the Eugene/Springfield Metro Area 10.6.1 Probable Maximum Loss Study of City BuiLdings in Eugene A probable maximum loss study for 20 City-owned buildings in Eugene was completed in 2001 for two ~eve~s of ground shaking, representing probabilistic leve~s of shaking with a 10% and 2% probability of occurring over a 50-year time period. Ground shaking levels range from 0.137 g to 0.16 g and from 0.296 g to 0.353 g respectiveJy, for these two leve~s of probabilistic shaking. The variation for a given probability of shaking represents variation due to local soi~ conditions. Estimated building damages (as percentage of replacement value) range from 2.5% to 32% and from 8.3% to 60.2%, for the two levels of probabilistic shaking. Buildings with high seismic vulnerability (that is, expected high levels of damage) include City the Overpark at 10th and Oak, the Hult Center, the Hu~t Center Parking structure, the Public Works Administration Building, and the Public Works Maintenance Building #1, a~ of which are estimated to have 40% or greater damage at the higher level of ground shaking. 10.6,2 DOGAMI Study of 200 Buildings DOGAMI (1999) completed a preliminary loss estimate study of 200 representative buildings using FEMA's HAZUS loss estimation methodology. For ground shaking of 0.3 g (similar to the higher level in the 2001 probable maximum loss study discussed above). For 200 buildings only, total building structural and non-structural damages were estimated at about $39,000,000, with total direct economic losses of about $110,000,000, including contents, business inventory, and income losses. 10,6,3 Windshield Survey and General Comments A "windshield" survey means a quick, preliminary seismic risk evaluation of a building or other facility, based on readily observable external attributes. A windshield survey may literally be done from a vehicle, but more commonly includes a quick walk around inspection. Conclusions drawn from such preliminary evaluations must be interpreted carefully as giving only a general indication of the probable level of seismic risk posed by the building or facility. Overall, a majority of the building inventory in the Eugene/Springfield Metro Area is residential with most residential structures being wood frame buildings. In general, wood frame buildings perform wel~ in earthquakes, with a few notable exceptions. Wood frame buildings with the following characteristics are generally substantially vulnerable to major seismic damage: 1) sill plates not bolted to foundation, 2) cripple wall perimeter systems, and 3) buildings on steep slopes, partially supported on "sti~tso" Cripple wa~l perimeter systems are short wooden wal~s which raise the first floor elevation above grade by typically about 2 to 4 feet. Unbolted sil~ p~ates and cripple 10-16