| 12.5 | Flood of record. Highway 395 in W Walker River Canyon closed for months. Massive destruction to infrastructure and economy including transportation, power, water, homes, businesses, etc. Area isolated. At this stage, 6.5 mile stretch of Highway 395 completely scoured with debris from canyon deposited in the town of Walker. Approximately 12,500 cfs with a 1 in 500 chance (0.2 | | 11.5 | Near record flooding. Area cut off as most transportation routes into area destroyed/flooded. Massive destruction of infrastructure/economy including power, roads, business, water, homes, etc. Approximately 10,000 cfs with a 1 in 200 chance (0.5 | | 10.7 | FLOOD DISASTER FROM WALKER RIVER CYN TO TOPAZ LAKE IN ANTELOPE VALLEY...IN SMITH VALLEY/WELLINGTON AREA...AND IN MASON VALLEY YERINGTON AREA. WIDESPREAD FLOOD DAMAGE TO ROADS...BRIDGES...HOMES AND STRUCTURES ALONG RIVER. SEVERE DAMAGE TO US 395 IN WALKER CYN...AND NV HWY 208 IN SMITH VALLEY-WILSON CYN...THESE HIGHWAYS PROBABLY CLOSED. ABOUT 8200 CFS...ABOUT A 1 IN 100 CHANCE (1% CHANCE) ANY YEAR. HISTORICALLY...THIS FLOW HAS BEEN REACHED OR EXCEEDED ONLY ONCE...IN JAN 1997 (12,500 CFS). | | 10.0 | FLOOD DISASTER FROM WALKER RIVER CYN TO TOPAZ LAKE IN ANTELOPE VALLEY...IN SMITH VALLEY/WELLINGTON AREA...AND IN MASON VALLEY YERINGTON AREA. WIDESPREAD FLOOD DAMAGE TO ROADS...BRIDGES...HOMES AND STRUCTURES ALONG RIVER. SEVERE DAMAGE TO US 395 IN WALKER CYN...AND NV HWY 208 IN SMITH VALLEY-WILSON CYN...THESE HIGHWAYS MAY BE CLOSED. EST. FLOW 6800 CFS...ABOUT A ONE IN 50 CHANCE...OR 2% CHANCE...ANY YEAR. HISTORICALLY...THIS FLOW HAS BEEN REACHED OR EXCEEDED ONLY TWICE...IN DEC 1937 AND JAN 1997. | | 9.5 | MAJOR FLOODING FROM WALKER RIVER CYN TO TOPAZ LAKE IN ANTELOPE VALLEY...IN SMITH VALLEY/WELLINGTON AREA...AND IN MASON VALLEY YERINGTON AREA. WIDESPREAD FLOODING OF LOWLANDS...ROADS...BRIDGES...HOMES AND STRUCTURES ALONG RIVER. TRANSPORTATION AFFECTED WITH DAMAGE TO US 395 IN WALKER CYN...AND NV HWY 208 IN SMITH VALLEY-WILSON CYN. EST. FLOW 5600 CFS...ABOUT A 1 IN 30 CHANCE (3% CHANCE) ANY YEAR. HISTORICALLY...THIS FLOW HAS BEEN EXCEEDED ONLY THREE TIMES...IN DEC 1937...NOV 1950 AND JAN 1997 FLOODS. | | 9.2 | Major flooding through reach and in Mason Valley and Yerington. Many buildings, roads flooded/washed out, major damage to agricultural lands, much sandbagging. Transportation affected. Severe damage to Highway 395 in W Walker Canyon. Approximately 5000 cfs with a 1 in 20 chance (5 | | 9.0 | MODERATE TO SIGNIFICANT FLOODING OF LOWLAND...PASTURE...RURAL ROADS...SOME YARDS AND BASEMENTS ALONG RIVER IN ANTELOPE AND SMITH VALLEYS. FLOODING OF STRUCTURES LIMITED IN ANTELOPE AND SMITH VALLEYS...THOUGH SANDBAGGING IS NECESSARY. HOWEVER...IN MASON VALLEY/YERINGTON AREA...FLOODING OF STRUCTURES IS SIGNIFICANT. IN JULY 1995...SEVERAL HOMES...BUSINESSES AND 1000S OF ACRES OF FARMLAND IN MASON VALLEY WERE FLOODED...WITH LEVEES OVERTOPPED. 4600 CFS...ABOUT A 1 IN 15 CHANCE...OR 7% CHANCE...ANY YEAR. | | 8.5 | MINOR TO MODERATE FLOODING OF LOWLANDS...PASTURE AND SOME RURAL ROADS ALONG RIVER FROM WALKER TO TOPAZ LAKE CA. MODERATE FLOODING ON THE LOWER WEST WALKER...IN WELLINGTON/SMITH NV AREA...AND MAINSTEM WALKER...IN THE MASON VALLEY/YERINGTON AREA. SOME SANDBAGGING OF STRUCTURES WILL LIKELY BE NECESSARY IN THE MASON/YERINGTON AREA. ABOUT 3700 CFS...A 1 IN 10 CHANCE (10% CHANCE) ANY YEAR. | | 8.0 | FLOOD STAGE...SOME MINOR FLOODING OF LOWLANDS...PASTURE AND RURAL ROADS. ABOUT 2900 CFS...A 15% CHANCE ANY YEAR...OR ABOUT A ONE IN 7 CHANCE ANY YEAR. MAXIMUM DIVERSION TO TOPAZ LAKE IS ABOUT 1300 CFS...REMAINDER GOES DOWN THE WEST WALKER TO WELLINGTON/SMITH VALLEY. IF TOPAZ IS RELEASING...FLOW AT WELLINGTON WILL BE TOPAZ RELEASE PLUS AMOUNT GOING DOWN WEST WALKER BELOW TOPAZ DIVERSION. | | 7.5 | MONITORING STAGE, NO FLOODING. ABOUT 2250 CFS...ABOUT A 20% CHANCE ANY YEAR (5-YEAR RETURN PERIOD). NOTE THAT MAXIMUM DIVERSION TO TOPAZ LAKE IS ABOUT 1300 CFS...REMAINDER GOES DOWN WEST WALKER TO WELLINGTON/SMITH VALLEY. IF TOPAZ IS RELEASING...FLOW AT WELLINGTON WILL BE TOPAZ RELEASE PLUS AMOUNT GOING DOWN WEST WALKER BELOW TOPAZ DIVERSION. |
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1) 12.63 ft on 01/02/1997
2) 9.90 ft on 12/11/1937
3) 8.92 ft on 07/09/1995
4) 8.78 ft on 07/03/1907
5) 8.71 ft on 05/19/2006
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1) 4.00 ft on 12/03/1924
2) 4.00 ft on 08/27/1931
3) 4.16 ft on 11/19/1977
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