DWR_2668988

• Title: STREAM FLOW DATA FOR COLORADO
• Year: 2003
• Document Type - Publications and Reports: Streamflow Report

PLATTE RIVER BASIN

06724000 ST. VRAIN CREEK AT LYONS, CO

LOCATION.--Lat 40°13'05", long 105°15'34", in NW¼NW¼ sec. 20, T.3 N,, R.70 W., Boulder County, Hydrologic
Unit 10190005, on left bank 75 ft southwest of U.S. Highway 36 (State Highways 7 and 66) at
southeast edge of Lyons, 400 ft upstream from St. Vrain Supply Canal, and 0.4 mi downstream from
confluence of North and South St. Vrain Creeks.

DRAINAGE AREA AND PERIOD OF RECORD.--212 mi². Aug. 1887 to Sep. 1891, June 1895 to current year. Monthly
only data for some periods. Water quality data available from Oct. 1977 to Feb. 1981.

GAGE.--Water-stage recorder with satellite telemetry in timber shelter. The DCP is the primary record with
chart recorder as backup. Supplemental outside staff gage. (NEW GAGE). Bubbler and manometer stage
sensors (on separate orifice lines) in a wooden shelter, with no stilling well. Primary reference
is an outside chain gage. Chart back up exists for periods when the manometer was operating; Two
different bubbler instruments were used during the season—a Sutron Accububbler and a Design Analysis
WaterLog system.

REMARKS.--(OLD GAGE) Primary record is hourly data taken from satellite monitoring with chart back up on
the stilling well. From October 1 to March 24 (1000), record was taken from the old gage. This
record is complete and reliable except for: December 24-27, 2002—inlets frozen; February 7-13,
2003—inlets frozen; February 24-March 8, 2003—inlets frozen. From March 24 (1100), record was taken
at the new gage at a different datum. Primary record is hourly data taken from satellite monitoring
using a bubbler with chart back up from the manometer. The record is complete and reliable except
for: April 11-15; June 19-20—Bubbler and Manometer failures; Mean daily chart (manometer) GH’s were
used for June 21-24, when the bubbler was not working. The record is good except for the following
periods which are estimated and poor: December 24-27; February 7-13; February 24-March 8; April
11-15; June 19-20. Station maintained and record developed by Merlin Friedrichsen.

RATING TABLE.-- SVCLYOCO22 USED FROM 01-OCT-2002 TO 24-MAR-2003; SVCLYOCO23 USED FROM 24-MAR-2003 TO 24-MAY-
2003; SVCLYOSH1 USED FROM 24-MAY-2003 TO 29-MAY-2003; SVCLYOSH2 USED FROM 29-MAY-2003 TO 30-SEP-2003

DISCHARGE, IN CFS, WATER YEAR OCTOBER 2002 TO SEPTEMBER 2003
MEAN VALUES

DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP

1 17 12 1.3 11 8.9 10 74 187 1070 355 167 117
2 23 11 1.1 9.9 10 10 109 173 873 350 145 95
3 20 11 .92 9.8 8.5 11 140 169 797 360 129 85
4 17 9.4 .92 9.7 6.6 11 135 169 738 344 136 84
5 16 9.3 .89 8.8 8.6 11 124 157 663 329 129 75
6 11 8.7 .76 8.9 8.2 12 111 145 570 308 114 74
7 9.3 8.5 .77 6.7 8 12 123 142 511 288 105 75
8 6.6 11 1.1 6.7 8 12 189 134 428 269 112 90
9 4.3 14 1.2 6.1 8 11 194 125 431 300 115 105
10 3.9 13 1.1 2.2 8 9.4 207 176 550 292 105 103
11 3.4 13 1.2 6.4 7 9.3 219 162 687 273 98 92
12 5 13 1.2 9.5 7 9 240 154 738 259 91 90
13 6.6 15 1.2 9.4 9 9.8 260 163 724 248 87 80
14 4.6 10 1 8.8 9.4 12 280 195 671 241 84 76
15 6 8.8 1.2 8.1 10 15 300 284 694 233 79 69
16 7.8 6 1.1 5.7 9.9 15 303 310 697 225 76 60
17 6.2 7.8 .53 7.4 8.8 18 253 281 642 231 76 55
18 4.4 9.9 .5 5.6 7.1 32 262 292 641 229 124 57
19 14 10 .47 9.4 7.6 34 244 318 640 240 146 57
20 18 9.8 1 7.4 8 36 203 343 610 235 116 55
21 16 9.7 1.7 6.7 7.6 38 175 326 555 229 96 50
22 18 8.4 2.8 4.6 6.5 53 156 335 543 217 89 47
23 20 10 2 7.9 6.8 68 167 421 531 211 81 43
24 23 11 3 9.4 9 88 163 482 506 201 79 37
25 21 11 4 8 11 76 161 563 485 193 85 35
26 17 6.6 6 8 13 78 176 620 380 204 85 34
27 17 3.1 8 9.4 11 87 190 686 329 200 75 33
28 17 1.5 9.9 9.5 10 72 193 883 355 211 69 31
29 19 1.5 9 6.7 --- 64 202 1010 400 218 72 30
30 16 1.4 9.1 7.6 --- 59 202 1070 395 220 160 28
31 14 --- 11 8.4 --- 59 --- 1080 --- 183 146 ---

TOTAL 402.1 275.4 85.96 243.7 241.5 1041.5 5755 11555 17854 7896 3271 1962
MEAN 13 9.2 2.77 7.9 8.6 33.6 192 373 595 255 106 65
AC-FT 798 546 171 483 479 2070 11420 22920 35410 15660 6490 3890
MAX 23 15 11 11 13 88 303 1080 1070 360 167 117
MIN 3.4 1.4 .47 2.2 6.5 9 74 125 329 183 69 28
WTR YR 2003 TOTAL 50583.16 MEAN 139 MAX 1080 MIN .47 AC-FT 100300
MAX DISCH: 1220 CFS AT 23:15 ON May. 30, 2003 GH 3.9 FT. SHIFT -0.36 FT.
MAX GH: 3.9 FT. AT 23:15 ON May. 30, 2003
FOR MORE COMPLETE OR DETAILED INFORMATION SEE DAILY OR MONTHLY RECORD.

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