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G~"l7{>() lJu Oi, 2 THE WEST Runoff was greatly excessive in northern California and in Oregon; some floods occurred, a few of which were record breaking, causing appreciable damage. Runoff in the Columbia River basin was generally ex- cessive and at Columbia River near The Dalles, Oreg., it was 160 percent of median aftf!r adjusting for storage in seven major power reservoirs. Runoff in the upper Colorado River basin was excessive for the ninth con- secutive month and fl6w of Colorado River near Grand C"anyon, Ariz.. was 140 percent of median. Runoff was also excessive in most of British Columbia. British Columbia.-Excessive discharge on the Co- lumbia, Fraser, Sproat, and Skeeoa Rivers was the re- sult of above normal temperatures and precipitation. Oregon.-Runoff remained above median and at the key station John Day River at Service Creek was record high for both February monthly and daily discharge. It '''w'as'ttie'-waj'mest 'F,ebruary1in"56' years' of 'record. Stor- age in all major storage reservoirs increased and was well above average. The early snowmelt resultpd in a record-high level for February in the key well near 'Burns. Idaho.-Floods in Weiser River basin occurred the latter part of the month as heavy rains caused high run- off from low and intermediate elevations in the basin. The only record-breaking discharge at a gaging station with more than 5 years of record was at Pine Creek near Cambridge where the peak discharge was 667 cfs from 54 sq miles. There was also high water in the lower part of Portneuf River basin. Colorado.-In the key well near Crystal River which had been dry for the past 3 months, the water level rose more than 5 feet to a record-high stage for February. Utah. -Streamflow was excessive for the ninth con- secutive month in the Colorado River basin and in south- western Utah, and at the key station Colorado River near Cisco was record high for February. Storage in the two principal reservoirs on Sevier River increased 33,000 acre-ft, the greatest increase for February during the past 20 years. In general, ground-water levels were tJ,igher than last year but lower than average. Nevada.-In Humboldt River basin runoff was exces- sive. Runoff was about median in other areas and ground-water levels in Paradise Valley rose to well- above average stages. Moderate precipitation on Feb. 24 melted some of the low-elevation snowpack and caused sharp rises in Carson, Truckeej and Humboldt Rivers. A few rural areas were flooded but damage was insignificant. Storage in major reservoirs increas- ed to about average for February. California. -Throughout northern California runoff wasexcessive as a result of the wettest February in recent years. Virtually all streams reached bankfull stages one or more times during the month. Flooding, confined almost entirely to the low-lying areas, caused damage estimated at between $5 and $10 million. Record-breaking floods (see table) oc.curred on some streams and at the key station Trinity River at Lewis- ton runoff was record high for February. At end of month the Sierra snow pack was apparently above aveJ:"age., and reservoir storage was consistently well ahov,e ave:rage for the month. In southern California runoff was well above median but water levels in key wells remained well below average. Arizona.-Streamflow was mostly in the median range, partly as a result of snowmelt. In the Tucson area runoff was the highest for February in nearly 10 years. Storage in .the res ervoirs on Salt and Verde Rivers increased 66,500 acre-ft to 556,500 acre-ft 77 percent of average. Storage in San Carlos Reser- voir increased 7,250 acre-ft to 63,640 acre-ft, almost 4,0 percent of average. New Mexico.-Runoff of most streams continued ex- cessive, partly as a result of early snowmelt. Storage in most reservoirs increased and in Elephant Butte and Caballo Reservoirs it reached 101 percent of the 19-' year average. MIDCONTINENT REGION Major floods that were the greatest since 1936 and 1942 occurred in Nueces and lower Guadulupe, Colo- rado, and Brazos River basins in Texas. Flood stages occurred on many streams in eastern Nebraska and northwestern Missouri near end of month and some local flooding occurred in Iowa as a result of ice jams. No significant changes in ground-water levels occurred. South Dakota:-Runoff was near median as abnor'- mally high temperatures caused the breakup of the relatively light ice cover on several streams aveI' the State. The first severe snowstorm of the season occurred the last 3 days of February, with moderate to heavy snowfall throughout the State. l I, Nehraska.-Flood stages occurred in many streams in the eastern part of the State during the last 2 days of the month as heavy rains fell on frozen ground. A new maximum daily discharge for February, 16, 000 cfs, occurred at the key station Elkhorn River at Waterloo. Streamflow remained near median in the Republican, Platte, and Loup River. basins., Ground-water levels generally rose, and, except in heavily pumped irrigation areasy were well above average.' Iowa. -Streamflow was deficient, there was no snow cover, and the ice on most streams went out without causing major floods. Ice jams and some local flooding of lowlands were common Feb. 23-25, when a sudden rise in temperatures caused rapid thawing. Several severe ice jams caused flooding of highways and inter- rupted traffic for short periods, Ice on Mississippi River was broken up as far north as the northern bound- ary of Iowa. Water levels in both key wells rose but were below average. Missouri.-Runoff was deficient during most of the month over the entire State. At month's end moder- ate precipitation on saturated ground caused some streams in the northern part of the State to reach bankfull stages. The level in the key well at Trenton, however, declined to a record-low stage for February.