HYDROGEOCHEMICAL AND GEOSPATIAL ANALYSIS OF ARID LAND SPRING WATERS TO DETERMINE CHANGES TO WATER AVAILABILITY DUE TO DROUGHT AND CLIMATE CHANGE CONDITIONS; ZUNI MOUNTAINS, NEW MEXICO

Severe drought coupled with land use practices has caused some springs of the Zuni Mountains, New Mexico to dry. Remaining regional springs are biological hotspots, including providing refugium for the endangered Zuni bluehead sucker (ZBS). The IPCC (2014) predicts that the regional snowline will rise 300 meters by 2050. To determine present snowmelt contributions we examined water from seven regional springs for major ions, stable isotopes (δD, δ18O) and tritium (TU) to estimate recharge timing. In addition, continuous temperature monitoring was performed at two of the springs which are home to ZBS. Geochemical results for three of the springs (δD=-86.6 to -95.22, δ18O=-11.5 to -13.11, TU=1.5 to 2.5) indicate recharge through predominately pre-1950’s snowmelt (two are home to ZBS). Continuous monitoring data also provides evidence of the flow path with spring water temperature both dampened (5-13 °C) and peaking two months after air temperature (2-18 °C). Isotopic data of the remaining four springs (δD=-74.94 to -89.5, δ18O=-10.89 to -11.94) indicates mixed recharge (rain/snowmelt) within the last 5-10 years (TU=4.1 to 5.7). ARCGIS is used to determine how much recharge area is lost for each of the springs. Preliminary results of GIS modeling indicate that a higher snowpack will result in more than a 60% loss of recharge area for all three of the springs that are snowmelt dominated and less than 20% loss of recharge area for the mixed springs. Implications of these results indicate that the springs which provide habitat for the ZBS are likely to dry with a rising snowline. Conversely, if precipitation amounts stay the same, four of the springs may not see a change to their water quantity. As the drought continues and the snowline rises, land managers will need to closely monitor remaining springs to better understand how the resources will be affected.