Floods of February 1962 in Southern Idaho and Northeastern Nevada GEOLOGICAL SURVEY CIRCULAR 467 Floods of February 1962 in Southern Idaho and Northeastern Nevada By Cecil A. Thomas and Robert D. Lamke GEOLOGICAL SURVEY CIRCULAR 467 Washington 1962 United States Department of the Interior STEW ART L. UDALL, SECRETARY Geological Survey THOMAS B. NOLAN, DIRECTOR free on application to the U.S. Geological Survey, Washington 25, 0. C. CONTENTS Page Page Abstract_____________________________ 1 Description of the floods Continued Introduction. __ _ ____ 1 Blackfoot River basin__________ 9 Cause of the floods ___________________ 5 Portneuf River basin ______________ 9 Description of the floods ______________ 5 South side tributaries of Snake River Bear River basin and Curlew Valley __ 6 below Portneuf River _____________ 12 Humboldt River basin _______________ 6 Big Wood River and Clover Creek Henrys Fork _________ _ _______ 7 basins __________________ 13 Idaho Falls - Blackfoot lowlands ______ 7 Snake River main stem _____________ 14 North and west of Snake River above Flood damage _______________________ 14 American Falls __________________ 8 Peak discharge data__________________ 15 ILLUSTRATIONS Page Figure 1. Map of southern Idaho and northeastern Nevada showing location of flood - measurement points, floods of February 1962, and isohyets for February 7-12 _______________________________________________ 2 2. Weather conditions for January and February 1962 at Elko, Nev., and west of Idaho Falls, Idaho _________________________________--______---------- 4 3. Discharge hydrograph, Malad River at Woodruff, Idaho, February 9-18, 1962___ 6 4. Discharge hydrographs for selected gaging stations in Nevada ________________ 7 5. View of Devils Gate Ranch on North Fork Humboldt River ____________________ 8 6. View of McKinley Ranch on Humboldt River ________________________________ 9 7. View of Battle Mountain during peak of February 14, 1962____________________ 10 8. New housing development in the flooded area northeast of Idaho Falls, Idaho ___ 11 9. Portneuf River looking upstream through Lava Hot Springs near the crest of the flood.____________________________________ -___ _-- 12 10. A break developing in a fill in U.S. Highway 30, 2 miles downstream from Lava Hot Springs _____________________________--__------------------__- 13 11. Discharge hydrographs for selected gaging stations on Snake River, Idaho _____ 14 12. Discharge hydrographs for gaging stations in Portneuf River basin, Idaho._____ 15 13. Discharge hydrograph for Clover Creek near Bliss, Idaho......._____________ 15 TABLES Page Table 1. Summary of flood damages in Snake River basin in Idaho, February 1962 _________ 14 2. Records of 1962 flood stages and discharges at selected gaging stations in Idaho and Nevada______________________________----_-_------_-------_-------____ 16 3. Records of flood stages and discharges by drainage basins, Idaho and Nevada _____ 22 in Floods of February 1962 in Southern Idaho and Northeastern Nevada By Cecil A. Thomas and Robert D. Lamkc ABSTRACT have been selected, and the high-water pro­ files have been marked but not surveyed. The floods of February 10-15, 1962, were the highest Other indirect measurements have been sur­ known on many streams in southern Idaho and northeastern veyed but not computed. Nevada. Some of the peak discharges have recurrence in­ tervals greater than a hundred years. The data in this report were collected as The floods resulted from an unusual combination of con­ part of the cooperative programs between the ditions, each of which contributed to the sudden severe Survey and various Federal and State agen­ flooding. These conditions were an extended period of cies. The district engineers for Idaho and above-freezing temperatures and prolonged light rainfall, an extensive area of snow at low altitudes, and deeply frozen Nevada, W. I. Travis and E. E. Harris, respec­ ground. The snow at higher altitudes did not contribute to tively, supervised the work of the Surf ace Wa­ the floods. ter Branch district personnel. Regional flood specialists, G.L.Bodhaine, H. Hulsing, and H. Runoff was greatest from watersheds at altitudes ranging F. Matthai, gave technical assistance in col­ from 4,500 to 6,500 feet. Flooding from small tributaries lecting and analyzing data and in preparing with large parts of their drainage within this range rank the report. Six engineers from districts other among the highest snowmelt floods ever recorded in Idaho than Idaho and Nevada were temporarily as­ and northeastern Nevada. The Snake River main stem had only minor flooding. signed to the flood areas to determine peak discharges as soon as possible after the The flood damage was the greatest ever experienced in flood. The field and office work of deter­ most of the flood area becaus,e of the large areas inundated mining peak discharges by indirect methods and because the value and amount of improvements has in­ were directed by C. A. Thomas and R. D. creased steadily. The total damage has been estimated as Lamke in Idaho and Nevada, respectively. more than $10 million. Weather data were furnished by the U.S. INTRODUCTION Weather Bureau, and estimates of flood dam­ age in Idaho were furnished by the U.S. Army The floods of February 1962 in southern Corps of Engineers. Idaho and northeastern Nevada (fig. 1) were the highest floods experienced in recent Data presented in this report include: de­ times and the most devastating. The flood scriptions of the cause, extent, and effects of area includes some of the most valuable ag­ the floods; hydrographs, table of mean daily ricultural and ranching land in both States discharges and discharges at indicated times and some of the most heavily populated areas for selected gaging stations; damage figures; in Idaho. peak stages and discharges for the February 1962 floods and for previous maximum floods This report presents available data col­ at selected gaging stations; peak discharges lected by the U.S. Geological Survey on these at miscellaneous sites; and whatever data floods. The data are provisional and fall are available for the incomplete indirect short of complete coverage. Many sites for measurements. indirect measurements of peak discharge FLOODS OF FEBRUARY 1962 IN SOUTHERN IDAHO AND NORTHEASTERN NEVADA INDEX MAP OF FLOOD AREA 119° ,29 Figure 1. Map of southern Idaho and northeastern Nevada showing location INTRODUCTION EXPLANATION Discharge determined Gaging stations 10 Discharge to be determined ,,. A9 Discharge determined Miscellaneous sites Dischargen»- t to* bet deterrmnedj ^ j Isohyet, showing precipitation in inches 111° 115 flood-measurement points, floods of February 1962, and isohyets for February 7-12. FLOODS OF FEBRUARY 1962 IN SOUTHERN IDAHO AND NORTHEASTERN NEVADA S3HONI Ml 'Hid3Q MOMS DESCRIPTION OF FLOODS fell at higher altitudes. In other areas heavy CAUSE OF THE FLOODS rainfall occurred,but the other factors caus­ These floods resulted from an unusual ing the flood were absent. The greatest total combination of conditions. These conditions rainfall measured within the flood areas was were prolonged low-intensity rainfall, mod­ 2.91 inches at Ashton, 65 miles northeast of erate amounts of snow on low-altitude areas, Idaho Falls. In Nevada the maximum was 2.06 warm days and nights, and a glaze of ice over inches at Turcarora, 30 miles northwest of deeply frozen ground. Total rainfall for the Elko. The greatest daily rainfalls recorded period February 7 12 is shown in figure 1. were 1.06 inches on'February 10 at Charles­ Temperatures, rainfall, and snow on ground ton, 60 miles northeast of Elko, and 0.90 inch during January and February at Elko, Nev., on February 12 at Preston, 60 miles south­ and west of Idaho Falls, Idaho, are shown in east of Pocatello, Idaho. The heaviest hourly figure 2. These sites, at opposite ends of the rainfall recorded in Nevada was 0.15 inch flood area, are in areas of intense flooding south of Elko. These amounts of rainfall or and show the similarity of weather conditions more could occur, on the average, once every that existed throughout the flood area. 2 years according to Weather Bureau Tech­ nical Paper 40, "Rainfall Frequency Atlas of The antecedent weather had a marked effect the United States." on the flood. Temperatures were 2° to 3°F below average during October, November, and The moderation in temperature that began December. The mean monthly temperatures in late January culminated in minimum tem­ for January were 4° to 9° below average. Al­ peratures of 20° or higher from February 9 ternate freezing and thawing of the existing through the flood period. The daytime tem­ cover of light snow occurred in December peratures were above freezing and were as and early January and transformed the shal­ much as 50° or higher. The rains plus the low snow into a mantle of ice over the ground. heat were sufficient to melt most of the shal­ Flooding occurred on January 8 in Goose low snow on low-altitude areas. This snow Creek and other small basins in southern ranged in depth from 1 foot at 6,700 feet to 0 Idaho when light rain fell on these watersheds at 4,500 feet in Nevada, and ranged from 3 and temperatures remained above freezing feet at the upper limits of the flood-generation for about 48 hours. In most low-altitude ba­ zone to 0 in Idaho. Greater amounts of snow sins, this short-lived thaw produced little were present at higher altitudes, but they did runoff but melted and settled the snow which not melt. froze quickly with the sharp drop in tem­ perature on January 9. This increased the The rain plus the melted snow ran off rap­ depth of frost and ice covering the ground. idly, as the frozen ground prevented infiltra­ tion. This resulted in floods with unusually Subfreezing temperatures continued over rapid rises of unusual magnitudes. the flood area from January 9 until the end of January.