Water-Data Report 2011 11372000 Clear Creek near Igo, CA Basin

LOCATION.--Lat 40°30′48″, long 122°31′23″ referenced to North American Datum of 1927, in SE ¼ NE ¼ sec.27, T.31 N., R.6 W., Shasta County, CA, Hydrologic Unit 18020112, on left bank, at old highway bridge on Redding-Igo Road, 0.3 mi downstream from South Fork Clear Creek, 1.0 mi northeast of Igo, 7.0 mi downstream from Whiskeytown , 8.3 mi southwest of Redding, and 10.4 mi upstream from mouth. DRAINAGE AREA.--228 mi².

SURFACE-WATER RECORDS PERIOD OF RECORD.--October 1940 to current year. CHEMICAL DATA: Water years 1958-79. WATER TEMPERATURE: Water years 1965-79. REVISED RECORDS.--WSP 1345: Drainage area. WSP 1395: 1941 (instantaneous maximum discharge). WRD CA-03-04: 1983 (peaks above base). GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 672.99 ft above NGVD of 1929. REMARKS.--Records fair. Low flow completely regulated by (station 11371700) since May 1963. Transbasin diversion from Trinity River through Judge Francis Carr Powerplant (station 11525430) to Whiskeytown Lake began in April 1963. Diversions from Whiskeytown Lake to Spring Creek Powerplant (station 11371600) began in December 1963. See schematic diagrams of the upper Sacramento River Basin, Pit River and McCloud River Basins, and Klamath and Trinity River Basins available from the Water Science Center. EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 24,500 ft³/s, Dec. 21, 1955, gage height, 13.75 ft; minimum daily, 9.0 ft³/s, Sept. 4-7, 1950. Since completion of Whiskeytown Dam in 1963, maximum discharge, 18,400 ft³/s, Mar. 3, 1983, gage height, 12.73 ft, from rating curve extended above 12,000 ft³/s, on basis of slope-area measurement of peak flow; minimum daily, 30 ft³/s, Oct. 10, 11, 1977.

U.S. Department of the Interior Suggested citation: U.S. Geological Survey, 2012, Water-resources data for the United States, Water U.S. Geological Survey Year 2011: U.S. Geological Survey Water-Data Report WDR-US-2011, site 11372000, accessed at http://wdr.water.usgs.gov/wy2011/pdfs/11372000.2011.pdf Water-Data Report 2011 11372000 Clear Creek near Igo, CA—Continued

DISCHARGE, CUBIC FEET PER SECOND WATER YEAR OCTOBER 2010 TO SEPTEMBER 2011 DAILY MEAN VALUES Day Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep

1 221 231 232 342 228 264 437 254 268 151 118 116 2 219 227 234 319 227 548 414 255 247 148 118 115 3 218 224 235 302 226 477 386 253 229 147 119 114 4 221 222 235 286 225 387 368 251 225 147 119 114 5 221 221 247 277 225 353 362 250 217 143 119 114 6 220 220 365 269 224 350 349 249 379 130 119 114 7 220 451 307 263 223 330 340 249 744 122 119 115 8 219 272 435 258 223 316 328 248 733 122 118 115 9 219 248 397 253 222 306 318 247 709 123 118 115 10 219 245 326 248 222 306 310 246 458 123 117 115 11 218 236 293 250 221 296 304 245 355 122 117 116 12 218 231 276 252 221 289 298 243 272 121 117 118 13 218 229 265 275 220 354 300 220 201 122 117 121 14 219 227 313 265 355 387 290 211 205 123 117 129 15 219 225 287 260 416 580 288 229 203 121 116 164 16 219 224 270 257 441 604 285 231 200 121 115 181 17 220 223 261 253 361 479 284 364 184 121 116 221 18 220 222 273 250 371 607 283 275 182 127 117 221 19 220 222 269 250 392 857 280 241 181 126 116 225 20 219 290 321 247 362 1,570 281 229 179 125 116 243 21 220 289 371 245 347 904 290 223 167 124 119 243 22 220 254 601 242 323 627 275 220 166 123 119 244 23 238 257 400 240 307 916 276 613 165 123 119 242 24 558 246 330 239 290 1,000 271 918 156 123 119 243 25 253 240 451 237 291 982 270 662 153 123 119 244 26 234 236 516 235 281 1,680 266 646 152 122 118 244 27 229 256 390 236 274 964 263 446 152 122 118 243 28 236 249 714 235 268 697 260 353 167 120 118 243 29 236 241 947 236 --- 565 258 275 175 119 118 243 30 234 236 482 238 --- 497 255 194 156 119 118 244 31 240 --- 382 229 --- 461 --- 224 --- 119 117 --- Total 7,285 7,394 11,425 7,988 7,986 18,953 9,189 9,764 7,980 3,922 3,650 5,319 Mean 235 246 369 258 285 611 306 315 266 127 118 177 Max 558 451 947 342 441 1,680 437 918 744 151 119 244 Min 218 220 232 229 220 264 255 194 152 119 115 114 Ac-ft 14,450 14,670 22,660 15,840 15,840 37,590 18,230 19,370 15,830 7,780 7,240 10,550

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1941 - 1962, BY WATER YEAR (WY) Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Mean 76.7 150 597 807 1,226 834 676 347 161 63.4 35.1 32.8 Max 373 427 2,336 2,513 5,753 2,595 2,431 773 289 126 64.6 89.7 (WY) (1951) (1951) (1956) (1941) (1958) (1941) (1941) (1957) (1953) (1941) (1941) (1957) Min 25.8 39.0 47.0 65.5 142 168 172 87.6 66.5 24.3 14.3 13.4 (WY) (1950) (1960) (1950) (1947) (1948) (1955) (1944) (1947) (1950) (1950) (1950) (1944)

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SUMMARY STATISTICS Water Years 1941 - 1962 Annual mean 413 Highest annual mean 1,092 1941 Lowest annual mean 128 1944 Highest daily mean 15,100 Mar 1, 1941 Lowest daily mean 9.0 Sep 4, 1950 Annual seven-day minimum 9.5 Sep 1, 1950 Maximum peak flow 24,500 Dec 21, 1955 Maximum peak stage 13.75 Dec 21, 1955 Annual runoff (ac-ft) 299,000 10 percent exceeds 929 50 percent exceeds 133 90 percent exceeds 27

STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1965 - 2011, BY WATER YEAR (WY) Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Mean 107 163 234 312 323 341 200 150 99.8 71.5 65.9 78.6 Max 317 299 625 1,358 1,612 3,437 668 592 268 155 151 225 (WY) (1993) (1974) (1965) (1970) (1998) (1983) (1974) (2003) (2010) (2010) (1999) (1999) Min 38.8 70.7 94.2 54.3 49.8 51.3 50.7 48.6 42.9 39.2 37.9 37.9 (WY) (1978) (1969) (1977) (1977) (1977) (1977) (1977) (1966) (1966) (1966) (1966) (1977)

SUMMARY STATISTICS Calendar Year 2010 Water Year 2011 Water Years 1965 - 2011 Annual total 109,867 100,855 Annual mean 301 276 180 Highest annual mean 570 1983 Lowest annual mean 57.9 1977 Highest daily mean 1,530 Jan 20 1,680 Mar 26 15,000 Mar 3, 1983 Lowest daily mean 93 Aug 26 114 Sep 3 30 Oct 10, 1977 Annual seven-day minimum 94 Aug 20 114 Sep 2 31 Oct 5, 1977 Maximum peak flow 3,290 Mar 26 18,400 Mar 3, 1983 Maximum peak stage 7.23 Mar 26 12.73 Mar 3, 1983 Annual runoff (ac-ft) 217,900 200,000 130,200 10 percent exceeds 483 443 304 50 percent exceeds 252 240 99 90 percent exceeds 98 119 50

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10,000

5,000

2,000

1,000

500 MEAN DISCHARGE, CUBICSECOND FEET PER

200

100 O N D J F M A M J J A S 2010 2011

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