• Mark L. Johnson

Water Woes X No Status Quo


Drought Status

Tortolita Alliance (TA) attended the Local Drought Impact Group (LDIG) Meeting via Microsoft Team on 11/10/21.


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.


Despite the second wettest monsoon season in the Tucson region, the Quarterly Long-Term Drought Status shows Severe, Extreme and Exceptional Drought conditions throughout the majority of Arizona. See graphics below.




Other information gleaned from the meeting:

  • Only 0.1" of rain was reported at the Tucson Airport in October----0.67" is normal.

  • November to-date temperature has been 4.4 degrees above normal and there has been no rain.

  • La Niña Conditions (higher temperatures and lower precipitation) are predicted for this winter.

  • The Colorado System is at 38% Capacity.

  • Colorado River Basin States are negotiating next cut-backs beyond the Drought Contingency Plan (DCP)


This situation remains dire and cannot be treated as status quo!


 



Marana Water Sustainability Meetings

TA attended the third Water Sustainability Meeting at the Marana Police Headquarters Meeting Room on 11/9. Marana Staff did a nice job presenting their water and wastewater programs. Glad to see Marana starting to be transparent about water issues. Unfortunately, it was lightly attended. There is one more scheduled for 11/30/21 at Sunflower Community Center at 3:00.


The information presented was essentially the same as that presented at the Town Council Study Session (8/24/21). See Water Woes XIII-Water Study Session Report A and Water Woes IX-Water Study Session Report B for the Study Session information.


Marana Water staff did confirm that Marana Water has about 2,804 acre-feet/year of water remaining in its Designated Assured Water Supply (DAWS) account. This is equivalent to about 9,347 lots (2,804/0.3 acre-feet per year per lot).


Yet Marana has approved 25,767 lots. This means that 16,420 lots have been approved with no DAWS available. Marana Water staff confirmed that until additional renewable water supplies are found, these 16,420 lots and any others that are approved, cannot be platted and no homes can be built. Go figure?



Marana Water needs to include a Reliability Factor of 75% as part of its water supply planning efforts. This means they should discount DAWS by 25% to take into account the increased aridification of the West and provide a cushion for Colorado River Water and other renewable water reductions.


 


Weather-Based Irrigation Controllers


In desert regions, upwards of 80% of residential water use occurs outside the home. Efficient landscape irrigation is the way to save a lot of water.


I'm amazed that neither Tucson Water or Marana Water recommend or offer incentives for weather-based irrigation controllers. Weather-based irrigation controllers automatically control the amount of irrigation water based on evaporation-transpiration (ET) in your area. Some weather-based controllers also add an additional adjustment for precipitation.


Your landscape contractor probably installed the standard Rain-Bird or similar irrigation controller for your irrigation system (see photo). It may allow seasonal adjustments but you have make the adjustment manually. Weather-based irrigation controllers make the seasonal adjustment automatically in real-time or based on a pre-programmed curve.


I am hoping that Tucson Water and Marana Water offer an incentive to replace these standard irrigation controllers with weather-based irrigation controllers like the Hunter Pro C with Solar Sync. Click on the button below to see video.