San Carlos Lake Status

A generous monsoon season and wet winter storms have boosted San Carlos Lake (SCL) to nearly 30 percent of capacity.  As of January 8, 2023, San Carlos held over a quarter-million acre feet of water.  On May 20, 2022, SCL was just about as dry as dry can get.  Back then it held a mere 1.34 acre feet of water.

An acre-foot is one of the most widely used measurements of water. It's the amount of water you would have if you covered an acre with one foot of water. The current SCL level is the highest January level in over five years.  Naturally, all of this water has excited downstream water users.  "San Carlos Irrigation and Drainage District staff and farmers are rejoicing," according to a January 3, 2023 article in the "Casa Grande Dispatch" newspaper. 

In this blog post we use charts to discuss the SCL status.

Here's the cause for the "rejoicing". There is a LOT more water in SCL this time of year than there has been in years!  This graph is used courtesy of the Office of The Gila Water Commissioner. You can find it and much other interesting information here: https://www.gilawater.org/

One of the factors that augmented inflow to SCL was the gi-normous Black Fire that ignited in late Spring 2023.  When the heavy monsoon rains hit the burn scar, runoff accelerated.
Source for above graph:  https://waterdata.usgs.gov/monitoring-location/09430500/

The Black Fire burned over 325,000 acres abd became the 2nd largest fire in New Mexico's modern history.  By comparison, the Whitewater-Baldy Fire burned 297,645 acres.    We added the lime green line to denote the Continental Divide.  You can see how much of the Gila River Watershed lies to the left of that lime green line.  Source of map:
https://inciweb.nwcg.gov/incident-maps-gallery/nmgnf-black-fire

Huge flows in the tippy-top of the Gila River Watershed always "attenuate" before they reach San Carlos Lake.  However, the USGS gage at Calva still shows well above average flows over a long period of time last year and so far this year.
Source: https://waterdata.usgs.gov/monitoring-location/09466500/

San Carlos Lake was still essentially dry as late as August 1st.  That's when the monsoon-induced flows really began to arrive to the parched reservoir.
Source: https://waterdata.usgs.gov/monitoring-location/09469000/

We copies this graph a few days ago.  The San Carlos Lake level has continued to rise and it's now over 251,000 acre-feet of water and 29.2% full.
Source: https://waterdata.usgs.gov/monitoring-location/09469000/

The quickest and easiest way to keep an eye on Gila River flows in Arizona is to use this link: 
https://waterdata.usgs.gov/az/nwis/current/?type=flow
Simply scroll down until you find the Upper Gila River section.

The San Carlos River rose to almost 8,400 cubic feet per second on January 2, 2023, as a result of the robust rain-on-snow event on New Year's Day.  USGS data shows the incorrect Max peak for today.
Source of San Carlos River hydrograph:
https://waterdata.usgs.gov/monitoring-location/09468500/

The actual peak flow for this calendar date was 54,800 cfs,  It was recorded 30 years ago today in 1993.
Source: https://waterdata.usgs.gov/monitoring-location/09468500/

The Upper Gila River Watershed snowpack is in "OK" condition for this time of year.  It's a whisker below normal but that's usually par for the course.  Note that the peak snowpack conditions occur much earlier in the Upper Gila than they do in other Southwestern watershed.  There is still plenty of time for additional snow to fall.  
Source:
https://wcc.sc.egov.usda.gov/reports/UpdateReport.html;jsessionid=K7yu-F9eph3SI5WaCH9GkGJ2nAbv__3sfnvUKl3E.nrcsprd0383

NOTE:  Although we listed the source for each of our graphics, it's actually difficult to find them on the newly-revised U.S. Geological Survey website. We'd be happy to help you find them if you are interested.  You can email me at: happytrailsforever@gmail.com  Thanks for reading.