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  • Writer's pictureMark L. Johnson

Water Woes XIII-Short-Term Drought Improvement

The Flats-Wild Mustang Trail


Helpful Facts/Hints

Blog Images-Just want to remind readers that you can click on any image (photo, graphic, etc.) to view in a larger window and actually scroll through all the images in that blog. You can also copy the images and save them if your computer software allows.

Water Year-The Water Woes series occasionally refers to the Water Year. The US Bureau of Reclamation (USBR) considers the Water Year to be October 1 through September 30 of the following year. This was done to include in a 12-month period, the snow that falls in late autumn which does not become runoff until it melts the following spring. One must be careful when looking at water data as some data is for the Water Year and other data is for the Calendar Year.

Short-Term Drought Status-average drought condition during last 4 weeks.

Long-Term Drought Status-statistical analysis of drought conditions during previous 2-5 year period compared to a 40-year historical record.

Colorado Basin River Forecast Center (CBRFC)-prepares daily reports and forecasts of precipitation and streamflow. CBRFC is division of the National Weather Service (NWS) which is a division of the National Oceanic and Atmospheric Administration (NOAA) which is part of the Department of Commerce.

24-Month Study-monthly studies that present hydrological descriptions and projected operations for the Colorado River system reservoirs for the next two years. The August 24-Month Study is the study used to determine shortage conditions for the upcoming calendar year. The 24-Month Study is prepared by USBR-Water Resource Group and they use the CBRFC streamflow forecasts in the 24-Month Study models. USBR is part of the Department of the Interior.


Drought Status

Tortolita Alliance (TA) attended the Local Drought Impact Group (LDIG) Meeting via Microsoft Team on 1/12/22.

LDIG is a bi-monthly gathering of local and state water agencies to discuss latest drought conditions across the state of AZ. Attendees include: TA, Marana Water, Tucson Water, Metro Water, National Weather Service-Tucson, Central Arizona Project (CAP), Arizona Department of Water Resources (ADWR), Pima County Office of Sustainability & Conservation (OSC) and more.

2021 Monsoon-Third Wettest On Record

The third wettest monsoon season in the Tucson region (see graphic above), along with some recent rains in late December have improved the Short-Term drought situation. The graphic below shows that 74% of Arizona is now considered abnormally dry and the red areas (extreme drought) are now minimal.

The same holds true for the Short-Term drought status in the Colorado River Basin. The graphic below shows mixed precipitation in October, very dry November and above normal precipitation in December.

However, the Quarterly Long-Term Drought Status for October-December still shows Severe, Extreme and Exceptional Drought conditions throughout the majority of Arizona. See graphics below.

The following additional information was gleaned from the meeting:

  • La Niña Conditions (Warm & Dry) are still predicted for the western US this winter

  • Lake Powell Inflow is predicted to be normal in the 2021/22 Water Year

  • However, the Colorado River System will remain in Tier 1 Shortage throughout 2022 and perhaps into the 2023

  • Pima County Office of Sustainability and Conservation monitors Pima County HCP Lands for biological and physical environmental change and data shows that mean temperatures are rising, mean winter precipitation is dropping and this is impacting species viability in the very dry years


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