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The water itself

Flow says how much; these sensors say what. USGS runs continuous temperature, conductance, dissolved-oxygen and turbidity probes at 100 Colorado sites. This is the latest reading at each, provisional until USGS reviews it, refreshed every three hours. Below the sensors: where sampled chemistry (nutrients, metals, bacteria) has been collected, watershed by watershed, from the Water Quality Portal. Drinking water is on each provider's page.
100
sensor sites reporting
100
water temperature
75
specific conductance
24
dissolved oxygen
25
turbidity
SiteDistrictTemp °CCond µS/cmDO mg/LTurb FNUAs of
BIG THOMPSON BL MORAINE PARK NR ESTES PARK, CO 402114105350101 Big Thompson River 6.2 2026-10-25 06:05
SOUTH BOULDER CR AT FOREBAY NR ELDORADO SPRINGS CO 06729470 Boulder Creek 8.9 59 9.4 1.6 2026-10-25 06:00
SOUTH PLATTE R AT 64TH AVE. COMMERCE CITY, CO. 06714215 South Platte Cheesman to Denver Gage 13.0 2026-10-25 05:45
SOUTH PLATTE RIVER ABV STRONTIA SPGS RESERVOIR, CO 06707525 South Platte Cheesman to Denver Gage 8.7 305 9.8 2.2 2026-10-25 06:00
SOUTH PLATTE RIVER AT ENGLEWOOD, CO. 06711565 South Platte Cheesman to Denver Gage 12.4 1200 7.5 2026-10-25 06:15
ARKANSAS RIVER ABOVE PUEBLO, CO 07099400 Fountain Creek 15.3 578 8.0 2026-10-25 05:15
ARKANSAS RIVER BELOW MOFFAT STREET AT PUEBLO, CO 07099971 Fountain Creek 13.8 681 2026-10-25 05:15
CLOVER DITCH DRAIN AT QUINN ST NR WIDEFIELD, CO 07105815 Fountain Creek 12.0 1860 2026-10-25 06:00
CLOVER DITCH DRAIN NEAR WIDEFIELD, CO. 07105820 Fountain Creek 15.8 1250 2026-10-25 06:00
FOUNTAIN CR BLW JANITELL RD BLW COLO. SPRINGS, CO 07105530 Fountain Creek 16.9 2026-10-25 05:45
FOUNTAIN CREEK ABV MANITOU AVE AT MANITOU SPGS, CO 07103695 Fountain Creek 8.1 6.3 2026-10-25 06:00
FOUNTAIN CREEK AT COLORADO SPRINGS, CO 07105500 Fountain Creek 9.4 2026-10-25 05:45
FOUNTAIN CREEK AT PUEBLO, CO. 07106500 Fountain Creek 11.6 1100 2026-10-25 05:15
FOUNTAIN CREEK AT SECURITY, CO 07105800 Fountain Creek 14.1 2026-10-25 05:50
FOUNTAIN CREEK BL 8TH ST., AT COLO. SPRINGS, CO. 07103707 Fountain Creek 8.7 2026-10-25 06:00
FOUNTAIN CREEK NEAR COLORADO SPRINGS, CO. 07103700 Fountain Creek 8.2 2026-10-25 06:10
FOUNTAIN CREEK NEAR FOUNTAIN, CO. 07106000 Fountain Creek 11.8 896 7.9 2026-10-25 06:00
FOUNTAIN CREEK NEAR PINON, CO 07106300 Fountain Creek 12.1 2026-10-25 06:15
JIMMY CAMP CREEK AT FOUNTAIN, CO. 07105900 Fountain Creek 12.3 2026-10-25 05:45
MONUMENT CR ABV WOODMEN RD AT COLORADO SPRINGS, CO 07103970 Fountain Creek 9.1 2026-10-25 05:50
MONUMENT CREEK AT BIJOU ST. AT COLO. SPRINGS, CO 07104905 Fountain Creek 9.6 2026-10-25 05:45
ARKANSAS RIVER AT GRANITE, CO. 07086000 Arkansas: Headwaters to Salida 4.2 182 2026-10-25 05:45
HALFMOON CREEK NEAR MALTA, CO 07083000 Arkansas: Headwaters to Salida 1.8 2026-10-25 05:30
ARKANSAS RIVER AT CANON CITY, CO. 07096000 Arkansas: Salida to Portland 10.2 271 2026-10-25 05:15
ARKANSAS RIVER AT PORTLAND, CO. 07097000 Arkansas: Salida to Portland 11.1 343 2026-10-25 05:30
ARKANSAS R. AT ST CHARLES MESA DIVER. AT PUEBLO,CO 07099969 Arkansas: Portland to Fowler 14.2 755 2026-10-25 05:45
ARKANSAS RIVER NEAR AVONDALE, CO. 07109500 Arkansas: Portland to Fowler 13.4 943 8.2 2026-10-25 06:00
BESSEMER DITCH AT ST. CHARLES WD NEAR PUEBLO CO 381312104321001 Saint Charles 15.0 587 4.3 2026-10-25 05:45
ARKANSAS RIVER AT CATLIN DAM, NEAR FOWLER, CO. 07119700 Arkansas: Fowler to Las Animas 12.6 1070 2026-10-25 05:15
ARKANSAS RIVER AT LAS ANIMAS, CO. 07124000 Arkansas: Fowler to Las Animas 13.5 848 2026-10-25 05:45
ARKANSAS RIVER NEAR ROCKY FORD, CO. 07120500 Arkansas: Fowler to Las Animas 12.2 1210 2026-10-25 05:15
PURGATOIRE RIVER AT ROCK CROSSING NR TIMPAS, CO. 07126485 Purgatoire River 14.5 2030 72.2 2026-10-25 04:30
PURGATOIRE RIVER NEAR THATCHER, CO. 07126300 Purgatoire River 14.2 3560 57.2 2026-10-25 05:30
ARKANSAS RIVER BELOW JOHN MARTIN RESERVOIR, CO. 07130500 Arkansas: Las Animas to Stateline 14.5 1720 2026-10-25 06:00
SAGUACHE CREEK NEAR SAGUACHE, CO 08227000 Saguache Creek 6.9 2026-10-25 05:15
TOMICHI CREEK AT GUNNISON, CO 09119000 Tomichi Creek 7.3 235 2026-10-25 05:30
ANTHRACITE CREEK ABOVE MOUTH NEAR SOMERSET 09132095 North Fork/Tribs. 7.1 2026-10-25 05:30
GUNNISON RIVER AT DELTA, CO 09144250 North Fork/Tribs. 11.2 827 8.8 502.0 2026-10-25 05:15
NORTH FK GUNNISON RIVER ABOVE MOUTH NR LAZEAR, CO 09136100 North Fork/Tribs. 9.8 518 9.4 150.0 2026-10-25 05:15
LOUTSENHIZER ARROYO AT HWY 50 NEAR OLATHE CO 383926107593001 Lower Uncompahgre River 11.4 1450 2026-10-25 06:00
UNCOMPAHGRE RIVER AT DELTA, CO 09149500 Lower Uncompahgre River 11.9 1200 8.7 259.0 2026-10-25 05:15
GUNNISON RIVER NEAR GRAND JUNCTION, CO. 09152500 Lower Gunnison River 11.6 1000 8.6 1160.0 2026-10-25 05:30
EAST RIVER AT ALMONT, CO 09112500 East River Basin 6.9 294 2026-10-25 05:15
EAST RIVER BELOW CEMENT CREEK NR CRESTED BUTTE, CO 09112200 East River Basin 5.8 257 2026-10-25 05:15
GUNNISON RIVER NEAR GUNNISON, CO. 09114500 East River Basin 7.1 253 8.9 5.0 2026-10-25 06:15
SLATE R AB BAXTER GL @HWY 135 NR CRESTED BUTTE, CO 385106106571000 East River Basin 5.0 160 2026-10-25 05:15
TAYLOR RIVER AT ALMONT, CO. 09110000 East River Basin 5.7 150 2026-10-25 06:00
TAYLOR RIVER AT TAYLOR PARK, CO. 09107000 East River Basin 2.5 126 2026-10-25 06:00
DOLORES RIVER AT BEDROCK, CO 09169500 Paradox Creek 11.1 1210 2026-10-25 05:15
DOLORES RIVER NEAR BEDROCK, CO. 09171100 Paradox Creek 13.0 646 2026-10-25 06:00
CEBOLLA CREEK NEAR POWDERHORN, CO. 09121800 Upper Gunnison River 4.4 2026-10-25 06:00
CIMARRON RIVER BLW CIMARRON CREEK AT CIMARRON, CO 09127000 Upper Gunnison River 7.9 576 2026-10-25 05:15
LAKE FORK AT GATEVIEW, CO. 09124500 Upper Gunnison River 7.2 220 2026-10-25 05:15
UNCOMPAHGRE RIVER AT COLONA, CO 09147500 Upper Uncompahgre River 9.4 526 9.0 167.0 2026-10-25 06:05
BLUE RIVER BELOW DILLON, CO. 09050700 Blue River Basin 6.4 273 2026-10-25 05:15
BLUE RIVER NEAR DILLON, CO 09046600 Blue River Basin 7.4 214 2026-10-25 06:00
BLACK GORE CREEK NEAR MINTURN, CO. 09066000 Eagle River Basin 3.5 588 2026-10-25 05:15
BOOTH CREEK NEAR MINTURN, CO. 09066200 Eagle River Basin 5.7 143 2026-10-25 05:15
EAGLE RIVER AT PRICE LANE BRIDGE NEAR GYPSUM, CO 09070050 Eagle River Basin 9.6 987 2026-10-25 05:30
EAGLE RIVER AT RED CLIFF, CO. 09063000 Eagle River Basin 5.3 257 2026-10-25 05:45
EAGLE RIVER BELOW MILK CREEK NEAR WOLCOTT, CO 394220106431500 Eagle River Basin 7.7 837 2026-10-25 06:15
EAGLE RIVER NEAR MINTURN, CO 09064600 Eagle River Basin 5.4 149 2026-10-25 05:15
GORE CREEK ABOVE BIGHORN PARK NEAR VAIL, CO 09066060 Eagle River Basin 4.6 317 2026-10-25 05:30
GORE CREEK AT MOUTH NEAR MINTURN, CO 09066510 Eagle River Basin 7.1 498 2026-10-25 05:15
GORE CREEK AT UPPER STATION, NEAR MINTURN, CO. 09065500 Eagle River Basin 4.2 101 2026-10-25 05:30
MIDDLE CREEK NEAR MINTURN, CO. 09066300 Eagle River Basin 5.1 249 2026-10-25 05:15
ROARING FORK RIVER AB DIFFICULT C NR ASPEN, CO. 09073300 Roaring Fork River Basin 5.0 76 2026-10-25 05:30
ROARING FORK RIVER AT GLENWOOD SPRINGS, CO. 09085000 Roaring Fork River Basin 9.2 633 9.1 30.9 2026-10-25 05:45
ROARING FORK RIVER BLW MAROON CREEK NR ASPEN, CO 09076300 Roaring Fork River Basin 6.4 394 2026-10-25 06:00
ROARING FORK RIVER NEAR EMMA, CO 09081000 Roaring Fork River Basin 8.2 427 2026-10-25 05:30
COLORADO R ABV ROARING FORK R AT GLENWOOD SPGS, CO 393259107194801 Rifle/Elk/Parachute Creeks 11.5 1480 8.6 8.1 2026-10-25 06:05
COLORADO R BLW SOUTH CANYON CR NR GLENWOOD SPGS CO 09085160 Rifle/Elk/Parachute Creeks 10.7 1160 8.9 26.7 2026-10-25 06:05
MUDDY CRK BLW WOLFORD MTN RESER. NR KREMMLING, CO 09041400 Muddy/Troublesome Creeks 11.8 620 8.0 2026-10-25 05:30
FRASER RIVER AT MOFFAT TUNNEL AT WINTER PARK, CO 09023561 Upper Colorado/Fraser Rivers 4.0 134 2.0 2026-10-25 06:00
FRASER RIVER AT TABERNASH, CO 09027100 Upper Colorado/Fraser Rivers 6.3 137 2026-10-25 05:15
FRASER RIVER AT UPPER STA, NEAR WINTER PARK, CO. 09022000 Upper Colorado/Fraser Rivers 2.6 139 2026-10-25 05:15
FRASER RIVER AT WINTER PARK, CO. 09024000 Upper Colorado/Fraser Rivers 4.4 160 2026-10-25 06:00
FRASER RIVER BLW CROOKED CR AT TABERNASH CO 09033300 Upper Colorado/Fraser Rivers 6.3 2026-10-25 05:15
FRASER RIVER BLW MOFFAT TUNNEL AT WINTER PARK, CO 09023562 Upper Colorado/Fraser Rivers 4.6 147 1.8 2026-10-25 06:15
ST. LOUIS CREEK NEAR FRASER, CO. 09026500 Upper Colorado/Fraser Rivers 3.4 111 2026-10-25 05:45
COLORADO RIVER AT CATAMOUNT BRIDGE, CO 09060799 Piney/Cottonwood Creeks 10.0 268 8.8 29.2 2026-10-25 05:30
COLORADO RIVER NEAR KREMMLING, CO 09058000 Piney/Cottonwood Creeks 8.4 255 8.7 23.2 2026-10-25 05:15
COLORADO RIVER ABOVE GLENWOOD SPRINGS, CO 09071750 Tribs. North of Colorado River 11.0 851 8.8 10.7 2026-10-25 05:45
COLORADO RIVER NEAR DOTSERO, CO 09070500 Tribs. North of Colorado River 10.4 562 8.4 7.9 2026-10-25 06:00
COLORADO R. ABV GUNNISON R. AT GRAND JUNCTION, CO 09106485 Lower Colorado River 11.6 1220 8.9 2026-10-25 05:45
COLORADO RIVER AT FRUITA, CO. 390828108441500 Lower Colorado River 12.0 1230 9.0 2026-10-25 06:00
COLORADO RIVER NEAR CAMEO, CO. 09095500 Lower Colorado River 11.2 1020 9.1 300.0 2026-10-25 06:00
COLORADO RIVER NEAR COLORADO-UTAH STATE LINE 09163500 Lower Colorado River 12.2 1330 8.1 2890.0 2026-10-25 05:45
WHITE RIVER ABOVE COAL CREEK NEAR MEEKER, CO 09304200 White River Basin 7.1 2026-10-25 05:15
YAMPA RIVER NEAR MAYBELL, CO 09251000 Lower Yampa River 9.6 371 2026-10-25 05:15
YAMPA RIVER AT DEERLODGE PARK, CO 09260050 Little Snake River 9.0 2026-10-25 05:15
GREEN RIVER ABOVE GATES OF LODORE, CO 404417108524900 Green River Basin 9.2 2026-10-25 06:15
YAMPA RIVER ABOVE STAGECOACH RESERVOIR, CO 09237450 Upper Yampa River 7.4 2026-10-25 05:45
YAMPA RIVER AT STEAMBOAT SPRINGS, CO 09239500 Upper Yampa River 9.3 239 2026-10-25 05:15
SAN JUAN RIVER NEAR CO RD 119 AT PAGOSA SPRINGS CO 09342600 San Juan River Basin 7.9 105 2026-10-23 08:45
ANIMAS RIVER AT DURANGO, CO 09361500 Animas River Basin 6.8 76.7 2026-10-25 05:30
ANIMAS RIVER BELOW SILVERTON, CO 09359020 Animas River Basin 3.2 116 16.9 2026-10-25 06:00
HERMOSA CREEK NEAR HERMOSA, CO. 09361000 Animas River Basin 8.0 2026-10-23 08:00
VALLECITO CREEK NEAR BAYFIELD, CO. 09352900 Los Pinos River Basin 5.4 2026-10-25 05:45
MUD CREEK AT STATE HIGHWAY 32, NEAR CORTEZ, CO. 09371492 McElmo Creek Basin 10.8 2026-10-25 05:30

Source: USGS National Water Information System instantaneous values, fetched 2026-10-25 06:22 UTC; public domain. A site with a Hydrohistorian gage page links to it; the rest link to USGS. Districts are assigned by location.

Where water has been sampled

Source Register of another agency · fetched 2026-10-08 · verify at Water Quality Portal ↗

The Water Quality Portal holds every sampling station USGS and the state, tribes and volunteer programmes have filed. Statewide it will not answer a dated query, so this is counted watershed by watershed: 66,743 stations across 88 HUC8 watersheds (39,135 USGS, 27,608 state and other), of which 3,105 reported a sample in the last 5 years on the state and tribal side. Results are not fetched here; each row links the portal's own file of its stations.

Watershed (HUC8)DistrictsStationsUSGSState, tribal, otherSampled, last 5 yMost active
Arkansas Headwaters 11020001 Arkansas: Headwaters to Salida, Wet Mountain Valley, Arkansas: Salida to Portland 6,859 1,062 5,797 176 Colorado Dept. of Public Health & Environment-WQCD
Middle South Platte-Cherry Creek 10190003 South Platte: Denver Gage to Greeley, South Platte Cheesman to Denver Gage, South Platte: Greeley to Balzac 6,611 5,718 893 203 Colorado Dept. of Public Health & Environment-WQCD
Animas 14080104 Animas River Basin 4,602 454 4,148 133 Colorado Dept. of Public Health & Environment-WQCD
Upper South Platte 10190002 North Fork of South Platte, Bear Creek, South Platte Cheesman to Denver Gage 3,600 2,666 934 157 Colorado Dept. of Public Health & Environment-WQCD
St. Vrain 10190005 Boulder Creek, St. Vrain Creek, South Platte: Denver Gage to Greeley 2,809 1,822 987 102 Colorado Dept. of Public Health & Environment-WQCD
Colorado Headwaters-Plateau 14010005 Roan Creek Basin, Divide Creek, Rifle/Elk/Parachute Creeks, Lower Colorado River 2,357 1,564 793 161 Colorado Dept. of Public Health & Environment-WQCD
Fountain 11020003 Fountain Creek 1,802 1,473 329 159 USGS Colorado Water Science Center
Clear 10190004 Clear Creek 1,709 788 921 69 Colorado Dept. of Public Health & Environment-WQCD
Upper Arkansas-John Martin Reservoir 11020009 Arkansas: Las Animas to Stateline, Arkansas: Fowler to Las Animas 1,641 1,326 315 69 Colorado Dept. of Public Health & Environment-WQCD
Upper Yampa 14050001 Middle Yampa River, Upper Yampa River, Lower Yampa River 1,596 1,202 394 100 Colorado Dept. of Public Health & Environment-WQCD
Upper Arkansas 11020002 Saint Charles, Arkansas: Salida to Portland, Arkansas: Portland to Fowler, Fountain Creek 1,561 1,190 371 65 Colorado Dept. of Public Health & Environment-WQCD
Upper Gunnison 14020002 Upper Gunnison River, East River Basin, North Fork/Tribs. 1,459 302 1,157 112 USGS Colorado Water Science Center
Cache La Poudre 10190007 Cache La Poudre River, Laramie River, Sand Creek 1,425 955 470 90 Colorado Dept. of Public Health & Environment-WQCD
Upper Arkansas-Lake Meredith 11020005 Arkansas: Portland to Fowler, Arkansas: Fowler to Las Animas, Fountain Creek 1,342 1,176 166 39 Colorado Dept. of Public Health & Environment-WQCD
San Luis 13010003 San Luis Creek, Trinchera Creek, Carnero Creek, Rio Grande 1,210 904 306 16 Colorado Dept. of Public Health & Environment-WQCD
Colorado Headwaters 14010001 Upper Colorado/Fraser Rivers, Muddy/Troublesome Creeks, Tribs. North of Colorado River, Piney/Cottonwood Creeks 1,156 525 631 123 USGS Colorado Water Science Center
North Fork Republican 10250002 Arikaree River 1,086 1,040 46 6 Colorado Dept. of Public Health & Environment-WQCD
Eagle 14010003 Eagle River Basin 1,053 364 689 112 Eagle River Watershed Council (ERWC) (Volunteer)
South Platte Headwaters 10190001 Upper South Platte 1,047 426 621 22 Colorado Dept. of Public Health & Environment-WQCD
Big Thompson 10190006 Big Thompson River, St. Vrain Creek 973 329 644 85 Colorado Dept. of Public Health & Environment-WQCD
Uncompahgre 14020006 Upper Uncompahgre River, Lower Uncompahgre River 956 473 483 64 Colorado River Watch
Middle South Platte-Sterling 10190012 South Platte: Balzac to Stateline, South Platte: Greeley to Balzac 933 772 161 47 Colorado Dept. of Public Health & Environment-WQCD
Piceance-Yellow 14050006 White River Basin 928 844 84 20 USGS Colorado Water Science Center
Alamosa-Trinchera 13010002 Alamosa La Jara, Culebra Creek, Trinchera Creek, Rio Grande +1 839 486 353 34 Colorado Dept. of Public Health & Environment-WQCD
Blue 14010002 Blue River Basin 835 339 496 57 Colorado Dept. of Public Health & Environment-WQCD
South Fork Republican 10250003 Republican River 754 722 32 5 Colorado Dept. of Public Health & Environment-WQCD
Purgatoire 11020010 Purgatoire River, Arkansas: Fowler to Las Animas 749 583 166 45 Colorado Dept. of Public Health & Environment-WQCD
Roaring Fork 14010004 Roaring Fork River Basin 748 289 459 132 Colorado River Watch
Lower Gunnison 14020005 Lower Gunnison River, North Fork/Tribs., Lower Uncompahgre River 681 444 237 74 USGS Colorado Water Science Center
Upper San Juan 14080101 Navajo River Basin, San Juan River Basin, Los Pinos River Basin, Navajo Reservoir +1 670 354 316 78 Southern Ute Tribe
Bear 11040005 Arkansas: Las Animas to Stateline 668 655 13 3 Colorado Dept. of Public Health & Environment-WQCD
East-Taylor 14020001 East River Basin 579 210 369 34 Colorado Dept. of Public Health & Environment-WQCD
Upper White 14050005 White River Basin 572 453 119 31 USGS Colorado Water Science Center
San Miguel 14030003 San Miguel River Basin 569 316 253 36 Colorado Dept. of Public Health & Environment-WQCD
Mancos 14080107 Mancos River Basin 561 105 456 73 Mountain Studies Institute (MSI)
Arikaree 10250001 Arikaree River 527 498 29 0
Chico 11020004 Fountain Creek, Arkansas: Portland to Fowler 509 484 25 59 USGS Colorado Water Science Center
Lower Yampa 14050002 Lower Yampa River, Little Snake River, Green River Basin 505 260 245 5 USGS Colorado Water Science Center
North Fork Gunnison 14020004 North Fork/Tribs. 429 270 159 24 USGS Colorado Water Science Center
Upper Dolores 14030002 Disappointment Creek Basin, Paradox Creek, West Dolores Creek/Tribs. 421 119 302 34 Colorado Dept. of Public Health & Environment-WQCD
Bijou 10190011 South Platte: Greeley to Balzac 400 386 14 8 USGS Colorado Water Science Center
Rio Grande Headwaters 13010001 Rio Grande 389 72 317 47 Colorado Dept. of Public Health & Environment-WQCD
North Platte Headwaters 10180001 North Platte River Basin 383 162 221 12 Colorado Dept. of Public Health & Environment-WQCD
Frenchman 10250005 Arikaree River 370 366 4 3 Colorado Dept. of Public Health & Environment-WQCD
Huerfano 11020006 Huerfano River, Cucharas River, Arkansas: Portland to Fowler 339 167 172 28 Colorado Dept. of Public Health & Environment-WQCD
Lower White 14050007 White River Basin 339 210 129 7 Colorado Dept. of Public Health & Environment-WQCD
McElmo 14080202 McElmo Creek Basin 333 59 274 16 Colorado Dept. of Public Health & Environment-WQCD
Big Sandy 11020011 Arkansas: Las Animas to Stateline 305 248 57 8 Colorado Dept. of Public Health & Environment-WQCD
Saguache 13010004 Saguache Creek, Carnero Creek, San Luis Creek, Rio Grande 290 227 63 10 Colorado Dept. of Public Health & Environment-WQCD
Crow 10190009 South Platte: Greeley to Balzac 278 261 17 2 Colorado Dept. of Public Health & Environment-WQCD
North Fork Smoky Hill 10260002 Republican River 263 263 0 1 USGS Colorado Water Science Center
Lone Tree-Owl 10190008 South Platte: Greeley to Balzac 245 234 11 4 Colorado Dept. of Public Health & Environment-WQCD
South Fork Beaver 10250012 Republican River 217 215 2 2 Colorado Dept. of Public Health & Environment-WQCD
Beaver 10190013 South Platte: Greeley to Balzac 211 193 18 8 Ducks Unlimited (Volunteer)
Sand Arroyo 11040004 Cimarron River Basin 206 206 0 1 USGS Colorado Water Science Center
North Fork Cimarron 11040003 Cimarron River Basin 185 185 0 0
Tomichi 14020003 Tomichi Creek 180 70 110 24 Colorado Dept. of Public Health & Environment-WQCD
Rush 11020012 Arkansas: Las Animas to Stateline 170 105 65 1 Colorado Dept. of Public Health & Environment-WQCD
Piedra 14080102 Piedra River Basin, Navajo Reservoir 160 93 67 6 Southern Ute Tribe
Conejos 13010005 Conejos Creek 153 70 83 14 Colorado Dept. of Public Health & Environment-WQCD
Kiowa 10190010 South Platte: Greeley to Balzac 150 143 7 2 Colorado Dept. of Public Health & Environment-WQCD
Middle San Juan 14080105 La Plata River Basin 150 88 62 9 Colorado River Watch
Horse 11020008 Arkansas: Fowler to Las Animas 149 104 45 0
Little Snake 14050003 Slater/Timberlake Creeks, Little Snake River 149 67 82 6 Mountain Studies Institute (MSI)
Apishapa 11020007 Apishapa River, Arkansas: Fowler to Las Animas 111 80 31 2 Colorado Dept. of Public Health & Environment-WQCD
Two Butte 11020013 Arkansas: Las Animas to Stateline 110 98 12 2 Colorado Dept. of Public Health & Environment-WQCD
Upper Green-Flaming Gorge Reservoir 14040106 Green River Basin 109 10 99 1 USGS Colorado Water Science Center
Lower Dolores 14030004 Dolores River Basin 103 66 37 8 Colorado Dept. of Public Health & Environment-WQCD
Little Beaver 10250013 Republican River 99 99 0 0
Pawnee 10190014 South Platte: Balzac to Stateline 95 92 3 1 USGS Colorado Water Science Center
Ladder 10260004 Republican River 73 71 2 0
Upper Cimarron 11040002 Cimarron River Basin 73 71 2 0
Lower South Platte 10190018 South Platte: Balzac to Stateline 71 53 18 3 Colorado Dept. of Public Health & Environment-WQCD
Stinking Water 10250006 Arikaree River 71 69 2 0
Lower San Juan-Four Corners 14080201 McElmo Creek Basin 66 15 51 4 USGS New Mexico Water Science Center
Smoky Hill Headwaters 10260001 Republican River 54 53 1 1 Colorado Dept. of Public Health & Environment-WQCD
Upper North Platte 10180002 North Platte River Basin 49 24 25 3 USGS Colorado Water Science Center
Westwater Canyon 14030001 Little Dolores River 49 12 37 0
Whitewoman 11030002 Arkansas: Las Animas to Stateline 47 39 8 0
Vermilion 14040109 Green River Basin 43 12 31 0
Upper Laramie 10180010 Sand Creek, Laramie River 40 5 35 3 Colorado Dept. of Public Health & Environment-WQCD
Cimarron Headwaters 11040001 Cimarron River Basin 39 27 12 3 Colorado Dept. of Public Health & Environment-WQCD
Montezuma 14080203 McElmo Creek Basin 37 31 6 0
Upper Rio Grande 13020101 Culebra Creek 27 27 0 0
Lower Lodgepole 10190016 South Platte: Balzac to Stateline 19 15 4 1 Colorado Dept. of Public Health & Environment-WQCD
Sidney Draw 10190017 South Platte: Balzac to Stateline 10 10 0 0
Rio Chama 13020102 Conejos Creek 3 0 3 0
Lower Green-Diamond 14060010 Green River Basin 0 0 0 0

Source: Water Quality Portal (USGS, EPA and the National Water Quality Monitoring Council), station search and the five-year summary profile, fetched 2026-10-08; public domain, citation requested by the portal. The five-year figure is the STORET/WQX side only, and legacy portal profiles stop carrying USGS samples added after March 2024. Watersheds join districts by area (data/district_huc8.json); a watershed that crosses the state line is counted for its Colorado stations only. Report a problem →