Status of climate and water resources at Casa Grande Ruins National Monument: Water year 2016
Filippone C and Raymond K. 2018. Status of climate and water resources at Casa Grande Ruins National Monument: Water year 2016. Natural Resource Report. NPS/SODN/NRR—2018/1629. National Park Service. Fort Collins, Colorado
Climate and hydrology are major drivers of ecosystems. They dramatically shape ecosys-tem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate and groundwater is central to assessing the condition of park biota and key cultural resources. This report combines data collected on climate with an overview of groundwater resources at Casa Grande Ruins National Monument (NM) for water year 2016 (October 2015–September 2016). Air temperatures were generally below normal (-1 to -4°F) from November through Janu-ary, whereas minimum and especially maximum air temperatures soared in February and March relative to 1981–2010 normals. Minimum air temperatures were generally above normal throughout the warm season. Annual precipitation at Casa Grande Ruins NM was only 72% of normal (6.57" vs. 9.18") in WY2016 when compared to normalized climate data for 1981–2010. Very little precipitation fell during December, February, and March, which are typically among the monument’s wettest months—yet in June, precipitation was about five times normal (0.25" vs 0.05"). There were no extreme precipitation events (>1") in WY2016, reflecting the overall drier-than-normal conditions. Groundwater conditions have significant impacts on Casa Grande Ruins National Monument and the surrounding area. The monument is located in the north-central section of the Eloy groundwater subbasin. Since about 1900, groundwater conditions in the Eloy subbasin have been increasingly dominated by agricultural use. Since the early 20th century, the Eloy subbasin has been in groundwater deficit, with more water pumped from the aquifer than was naturally replenished. This has resulted in substantial changes to the natural flow regime, declining wa-ter levels, and land subsidence. Groundwater loss has the potential to affect the water supply as well as the stability of structures through land subsidence.
- Type
- Published Report
- Authors
- Filippone, Colleen; Raymond, Kara
- Date of Issue
- 2018-05
- Publisher
- National Park Service
- Units
- CAGR , NRSS , SODN
- Keywords
- climate, groundwater, monitoring
- Subjects
- Ecological Framework: Air and Climate | Weather and Climate | Weather and Climate , Ecological Framework: Water | Hydrology | Groundwater Dynamics