| Flood Impacts |
| 34.0 | ABOVE 34.O FT...EXPECT FLOODING OF MUCH OF DOWNTOWN VANCOUVER...ALONG WITH MAJOR FLOODING ALONG THE COLUMBIA RIVER FROM VANCOUVER DOWNSTREAM TO LONGVIEW. SOME LOWER LEVEES MAY BE OVERTOPPED. |
| 31.0 | ABOVE 31.O FT...EXPECT MAJOR FLOODING. OVERTOPPING OF SOME LOWER LEVEES IS POSSIBLE. EXPECT WIDESPREAD INUNDATION ALONG THE COLUMBIA FROM VANCOUVER DOWNSTREAM TO LONGVIEW. TRIBUTARY RIVERS WILL BE BACKED UP. MANY INDUSTRIES ALONG THE COLUMBIA AND MOST SHIP TRAFFIC WILL BE AFFECTED. |
| 30.0 | ABOVE 30 FT...EXPECT WIDESPREAD FLOOD INUNDATION ALONG THE COLUMBIA FROM VANCOUVER DOWNSTREAM TO LONGVIEW. NUMEROUS ISLANDS AND SLOUGHS ON THE COLUMBIA UPSTREAM AND DOWNSTREAM OF THE I-5 BRIDGE ARE FLOODED. MANY INDUSTRIES ALONG THE RIVER HAVE HISTORICALLY CEASED OPERATIONS AT THIS LEVEL. |
| 27.0 | ABOVE 27 FT...EXPECT WIDESPREAD FLOODING OF LOW LYING FARMLAND...ISLANDS ON THE RIVER...AND SLOUGHS IN THE PORTLAND AND VANCOUVER AREA. HISTORICALLY...RIVER TRAFFIC HAS BEEN HALTED TO PREVENT WATER FROM OVERTOPPING THE LOWEST DIKES ALONG THE RIVER. |
| 24.0 | ABOVE 24 FT...EXPECT NUMEROUS SLOUGHS TO BEGIN FLOODING IN THE PORTLAND AND VANCOUVER AREA. NUMEROUS ISLANDS ON THE COLUMBIA RIVER BOTH UPSTREAM AND DOWNSTREAM FROM THE INTERSTATE 5 BRIDGE HAVE HISTORICALLY BEGUN TO FLOOD AT THIS POINT. ALSO EXPECT FLOODING OF PARKS AND LOWLAND AREAS NEAR THE SANDY RIVER CONFLUENCE ABOVE THIS LEVEL. |
| 20.0 | ABOVE 20 FT...EXPECT WIDESPREAD FLOODING OF UNDIKED LOWLAND AND AGRICULTURAL LAND...ALONG WITH FLOODING OF THE ACCESS ROAD UNDER THE NORTH END OF THE INTERSTATE BRIDGE. ISLANDS ON THE COLUMBIA RIVER DOWNSTREAM FROM THE INTERSTATE BRIDGE ARE THREATENED ABOVE THIS LEVEL. |
| 18.0 | ABOVE 18 FT...EXPECT FLOODING OF UNDIKED LOWLAND...PASTURE...AND FARMLAND TO BEGIN. THE MAIN AREAS IMPACTED HAVE HISTORICALLY BEEN FROM SAUVIES ISLAND DOWNSTREAM. |
| 16.0 | ABOVE 16 FT...FLOODING IN LOCALIZED AREAS BEGINS BUT IMPACTS ARE MINOR. |
