THE 1997 NEW YEAR'S FLOODS IN WESTERN NEVADA

July 1998

Floods have been described as the most devastating of all natural events, and Nevada has had its share of devastating floods in its relatively short history. In nearly 150 years of recorded history, western Nevada has been stricken with at least 11 major, regional, wintertime floods of the type that struck this area most recently in the opening days of 1997. There have also been numerous localized summertime flash floods, along with additional, smaller, regional, wintertime floods. The regional wintertime floods generally occur as a result of periods of heavy, prolonged, and frequently warm, subtropical rains, falling onto a heavy snowpack in the Sierra Nevada of western Nevada and eastern California; such was the case with the January 1997 floods of western Nevada and northern California.

This latest regional flood of is discussed in a recently released publication entitled: The 1997 New Year's Floods in Western Nevada (NBMG Special Publication 23). This report, produced in cooperation with the U.S. Geological Survey, UNR Cooperative Extension, UNR Department of Geography, and the National Weather Service, describes the January 1997 flooding (the "New Year's Floods") along the Truckee, Carson, and Walker Rivers in Nevada, and the effects of the floods in these river basins. Written for the general public and for planning agencies and other governmental bodies, this report traces, with maps, the route of the floods from the Nevada-California state line, through all the major cities and towns affected by the floods, to the terminus of the flooding rivers in Nevada.

The report traces the route of the floods along the three river basins in Nevada (see map), describes in some detail the damages inflicted by the floods to both urban and rural areas, and discusses the causes of the flooding, which began in some areas on New Year's Day. Flooding along all three river basins in Nevada inundated nearly 64,000 acres, caused direct damages estimated between $167,000,000 to $619,000,000, and claimed at least one, and possibly, two lives. Most monetary damage occurred along the Truckee River, in the cities of Reno and Sparks in Washoe County, due to the concentration of expensive business property located along the Truckee River in these cities, much of which suffered damages in the flooding. Additional hundreds of millions of dollars were lost to the Nevada economy due to disruptions in travel and lost business and taxes, and several landslope failures occurred as a result of the heavy rains prior to the onset of the floods. In all, the New Year's floods of 1997 were the most costly and damaging floods in the drainage basins of the Truckee, Carson, and Walker Rivers in the area's 150 years of recorded history.

The New Year's floods set new records for peak discharge (flow rate) and maximum stage (water surface height) at several U.S. Geological Survey stream gaging stations along the Truckee, Carson, and Walker Rivers in Nevada. For example, new records for stage were set at the Reno and Vista gaging stations on the Truckee River. Three stations (Gardnerville, Carson City, and Fort Churchill) on the Carson River set new records for both discharge and stage, and three gaging stations (Hoye Bridge, Hudson, and Schurz) on the Walker River set new records for discharge.

The report concludes with a discussion of flood insurance and flood mitigation techniques and procedures, and includes a county-by-county list of flood information and resources available to the public.

---Jim Rigby, Research Geologist