This section of the City's web site provides information about the city's floodplain and rivers, streams, creeks, and other drainageways in general. City personnel are available to provide specific flood and flood-related data and make site visits to review flood, drainage, and sewer problems. To speak with someone directly about these issues, please call the Public Works Department Development Services Section at 503-588-6211.
Overview
The City of Salem features the Willamette River and smaller tributaries, or streams, that are susceptible to annual flooding events that pose threats to life and safety and cause significant property damage. The streams include Battle Creek, Cinnamon Creek, Claggett Creek, Clark Creek, Croisan Creek, Davidson Creek, Gibson Creek, Glenn Creek, Golf Creek, Jory Creek, Laurel Creek, Little Pudding, Mill Creek, Mill Race, Pettyjohn Creek, Powell Creek, Pringle Creek, Scotch Creek, Shelton Ditch, Waln Creek, and Winslow Creek. The City of Salem has more than 4,000 acres of floodplain and approximately 3,000 individual parcels that are partially or entirely located within the floodplain. In Salem, flooding generally occurs when: (1) unusually warm weather mixed with heavy rains melt snow in the higher elevations and flood local streams (referred to as a "Pineapple Express") and/or (2) ongoing development within the City continues to displace natural areas that have historically functioned as flood storage.
Recent Flooding Events
While some sort of seasonal flood-related damage occurs nearly every year, many mid-Willamette Valley residents may be familiar with the legendary floods of the 19th Century. The largest flood on record on the Willamette River occurred in 1861. Since then, the construction of flood control dams in the 1940s and 1950s has changed the pattern of flooding significantly. However, flooding still occurs as many residents may remember the "Christmas" flood of 1964, which was rated "approximately a 100-year flood" by the Federal Emergency Management Agency (FEMA) and may be the most damaging in Oregon's history. The "Christmas" flood caused $157 million in damage, and 20 Oregonians lost their lives.
The "Christmas" flood occurred as a result of two storms, one on December 19, 1964, and the other on January 31, 1965. These storms brought record-breaking rainfall that exacerbated near record early season snow depths. The Willamette River crested at 29.7 feet in Salem, nearly 10 feet above flood stage, and many other streams in Salem overflowed their banks. The floodwaters rendered the sewage treatment plant inoperable causing raw sewage to be channeled directly into the Willamette River. One hundred and twenty-one patients were evacuated from the Salem Memorial Hospital and fifteen families in the Turner/Salem area were evacuated from their homes.
The next two major storm events happened in January 1974 and February 1986. Both of these were caused by heavy snow accumulations followed by heavy rains and warm weather, causing the snow to melt. Again, these flood events caused the sewage treatment plant to be inoperable.
The flooding events of February and November 1996 represent the most recent significant flooding. In February 1996, prolonged precipitation accompanied by early snow melt caused many rivers and creeks throughout the Willamette River watershed to rise substantially. The Salem area saw nearly the 100-year flood levels, causing flooding in both rural and urban areas. Damage to City businesses, residences, and infrastructure was tremendous, and most of the City's residents were affected by the substantial impact to the transportation system and the loss of potable water, in addition to the many who suffered damage to personal property. Claims filed under FEMA's National Flood Insurance Program (NFIP) from City residents and businesses accounted for almost one-third of the claims filed for Marion County in 1996.
Although the floods of 1996 represented a large-scale disaster, they are not unprecedented within the recent past. While the 1996 events were devastating to the entire region, the floods of 1861, 1890, and 1964 exceeded the 1996 events in terms of velocity and volume of water. All four floods have been estimated to either exceed or come relatively close to the so-called "100-year flood," or Base Flood, and all within a time frame of about 130 years.
|
|
