Friendship Cruise Communications

River Flow Rates


River flow rates can have a dramatic effect on the difficulty of the Cruise, and, hence, upon the amount of communications traffic generated by boaters in trouble. Low water causes sand bar difficulties on the Green and a more difficult passage through “The Slide,” the one section of whitewater on the course, on the Colorado. High water at that time of year can mean difficulty with driftwood, particularly if a new peak has just been attained.

In the most successful cruises of recent years, flow rates on both rivers were between 20,000 and 25,000 cubic feet per second at the time of the Cruise.

The Green River flow rates are the ones measured at the town of Green River. The Colorado rates are measured at Cisco.


River Flowrate Graph


Flow Rates for 2011
(in cubic feet per second)
Date   Green at
Green River,   
UT
Colorado at   
Cisco
Cataract Canyon
(below confluence)
5-7 13,850  9,700 19,550 e
5-8 15,350 12,250 23,500 e
5-9 16,250 16,100 27,750 e
5-10 17,400 19,750 32,800 e
5-11 21,000 18,900 37,850 e
5-12 23,050 18,750 39,950 e
5-13 23,850 18,350 42,250 e
5-14 23,100 18,800 42,050 e
5-15 21,700 17,600 39,050 e
5-16 20,050 18,900 39,400 e
5-17 19,500 21,800 38,900 e
5-18 22,050 23,150 42,150 e
5-19 24,800 23,150 47,200 e
5-20 26,850 21,650 48,650 e
5-21 28,050 20,700 49,200 e
5-22 28,750 19,400 49,000 e
5-23 28,450 18,750 48,550 e
5-24 27,350 19,400 47,800 e
5-25 26,600 20,850 47,100 e
5-26 25,950 21,150 46,500 e
5-27 27.050 21,700 47,350 e
5-28 28,000 23,950 49,400 e
5-29 29,250 27,000 52,750 e
5-30 29,850 30,550 57,150 e
5-31 30,200 35,800 61,550 e
“e” = estimated

Additional Flow-Rate Sources

The data above are from the daily Recreational River Report issued by the Colorado Basin River Forecast Center. These figures include estimated flow for Cataract Canyon and estimates for periods when a gauging station is out of service.

Additional information about the flow rates is available from CBRFC and from the US Geological Survey (USGS). The links below show nearly real-time data from the gauging stations at Green River and Cisco. In addition, the CBRFC chart shows a prediction of flow rates several days ahead and the USGS chart shows points for a 100-year median flow.

River CBRFC USGS
Green (at Green River, UT) GRVU1 Hydrograph Green River Data
Colorado (at Cisco, UT) CLRU1 Hydrograph Cisco Data