Wednesday, March 9, 2011

Recommend Flows - Ifs, Ands and Buts

The Escalante River may be one of the hardest Western rivers - perhaps just plain impossible - to accurately predict the expected flow while planning a trip.

Before my first trip, I poured over every bit of information in print and online that could be found with a special interest in understanding what people were saying about 'recommended cfs flows' before I started.  Truth is, my mind had already been made at that point and whatever information was to be found and considered was for informative purposes only.  Every thing I could find pointed that a minumum 50 cfs would be required.

This presents a HUGE problem.  Looking at USGS water site one can almost immediately see that an expected flow in spring time at this rate is all but unheard of.  One place I found said a combined flow with Boulder Creek of 50 cfs would be sufficient. Problem there is that no information is available for flow rates on Boulder Creek.  Finally in publication I found a recommendation as low as 30 cfs on upper Escalante to make the trip possible.  As an example, the highest annual average mean value I could find on the site was in 2005 and was 37.4.


Hopefully this will not be the first time I have said this here, I am not an expert of anything.  I can tell only the stories of my own experience.  I have successfully traveled consecutively twice from Highway 12 to Lake Powell.  Neither of my trips included a reading near the recommended levels, in fact my first trip was at a very low reading.  This trip required pushing, kicking and determination to complete at this low of a level.  Here are the flows on the dates of my travels.

2009

2010

Before we take this further it's important to know a little information about the gauging station that provides the only real-time information available.  The actual gauge is located just outside of the town of Escalante and almost 17 miles from the put-in on Highway 12.  The river at this earlier point most times of the year is  little more than what I might call an irrigation canal.  Last year the USGS posted a new picture on the website that I would consider a very generous flow, you can notice the heavy silted brown color that usually runs at bit clearer during this time of year when I have visited the station.

Photo from USGS Real-Time Water Date website - used as reference only
If the date on the picture is correct the flow at the time this was taken would have been exactly 16cfs.  The day that this article was written is 3/8/2011 and the reading currently available from this location is 5.8 cfs almost 3 times lower than what we see in the picture.  A reading of 16 by this early date might have implied rain in the area , this would further explain the heavy silting.   I am hoping for a serious spring storm this year while Im in town so I can inspect this station at a higher flow.  I honestly can't imagine what a reading at 400 or above would look like here, let alone fit in this stream bed.  I'm off track....

Highway 12 is also the confluence of the Escalante with Calf Creek.  Although not measured, this stream provides some additional relief and is located just after bridges west side.  I found this great example on the Utah State University web site.  
Photo from Utah State University website - used as reference only.

6 miles downstream is the confluence of the Escalante with Boulder Creek.  Boulder doesn't seem to be perennial.  Although it can provide some significant volumes when running.  In 2009, the first year I floated this was dry and did not contribute.  I have to admit I was somewhat dismayed as this seemed likely to have still been flowing on 6/13/09.


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