Colorado River — water-availability stoplight map

Main stem flows top to bottom (headwaters → Gulf of California). Tributaries branch left and right at their confluences.

Indicative first-pass · current as of 2026-10-09

Read before using
  • Colors use percent-of-capacity as a stand-in for the planned percentile-vs-history spine — treat as indicative.
  • Gray = not scored this pass: missing data, diversion structure, or flood-control dam. Gray is never "healthy."
  • Salt & Verde dams scored at the SRP system level, not per individual reservoir, when that source is available.
  • Critical elevations confirmed for Powell only. Mead's min-power pool needs verification.
Red — much below normal / critical
Yellow — below normal / watch
Green — normal or better
Gray — no usable data / n/a
Confluence
Headwaters
La Poudre Pass, Rocky Mountains, CO
Shadow Mountain Dam
Shadow Mountain Lake
data not yet gathered
Granby Dam
Lake Granby
data not yet gathered
Windy Gap Dam
Windy Gap Reservoir
small diversion reservoir
Upper Colorado tribs
Front Range water supply
Dillon Dam
Blue River
Green Mountain Dam
Blue River
Williams Fork Dam
Williams Fork River
Wolford Mountain Dam
Muddy Creek
Ruedi Dam
Fryingpan River
Grand Valley Diversion Dam
diversion structure, no reservoir
Price-Stubb Dam
diversion structure, no reservoir
Gunnison River
joins at Grand Junction, CO
Blue Mesa Dam
CRSP — Aspinall Unit
15.1% cap, 7412.8 ft
Morrow Point Dam
CRSP — Aspinall Unit
Crystal Dam
CRSP — Aspinall Unit
Ridgway Dam
Uncompahgre River
Taylor Park Dam
Taylor River
Dolores River
joins in eastern Utah
McPhee Dam
Dolores River
Green River
largest tributary · Canyonlands, UT
Fontenelle Dam
CRSP
78.9% cap, 6497.8 ft
Flaming Gorge Dam
CRSP Upper Basin
65.3% cap, 6006.4 ft
Soldier Creek Dam
Strawberry/Duchesne River
Starvation Dam
Duchesne River
Scofield Dam
Price River
Joes Valley Dam
San Rafael basin
Yampa & White rivers — free-flowing
San Juan River
joins into Lake Powell
Navajo Dam
CRSP Upper Basin
49.5% cap, 6017.0 ft
Ridges Basin Dam
Animas River
Vallecito Dam
Los Pinos River
Glen Canyon Dam
Lake Powell · min power 3490 ft · dead pool 3370 ft · start of Lower Basin at Lees Ferry
19.9% cap, 3519.0 ft
Little Colorado River
joins in the Grand Canyon
No major dams — free-flowing
Virgin River
joins into Lake Mead
No major main-stem dam — Sand Hollow is off-stream
Las Vegas Wash
joins into Lake Mead · Nevada (west bank)
no storage dam — erosion-control weirs only; carries ~200 MGD treated wastewater returns from Las Vegas Valley
Hoover Dam
Lake Mead
18.6% cap, 1037.7 ft
Davis Dam
Lake Mohave
88.3% cap, 637.5 ft
Bill Williams River
joins into Lake Havasu
Alamo Dam
Bill Williams River
Parker Dam
Lake Havasu
data not yet gathered
Headgate Rock Dam
diversion structure, no reservoir
Palo Verde Diversion Dam
diversion structure, no reservoir
Imperial Dam
diversion structure, no reservoir
Laguna Diversion Dam
diversion structure, no reservoir
Gila River
joins near Yuma, AZ
Coolidge Dam
Gila River
Painted Rock Dam
Gila River
Theodore Roosevelt Dam
Salt River Project
Horse Mesa Dam
Salt River Project
Mormon Flat Dam
Salt River Project
Stewart Mountain Dam
Salt River Project
Horseshoe Dam
Salt River Project
Bartlett Dam
Salt River Project
New Waddell Dam
Central Arizona Project
Morelos Dam
US–Mexico border · last dam on the river
diversion structure, no reservoir
Gulf of California
Sea of Cortez · river rarely reaches the sea
Sources (as of 2026-10-09): USBR Upper & Lower Colorado water operations and weekly hydrologic update; USBR Glen Canyon / Flaming Gorge operations pages; SRP Watershed Connection; public reservoir trackers. Tributary placement is schematic, not geographic: left — Upper Colorado tributaries, Green River, Virgin River, Las Vegas Wash; right — Gunnison, Dolores, San Juan, Little Colorado, Bill Williams, Gila.