Groundwater-level change contours for the Lahontan Valley shallow aquifer near Fallon, Nevada, 1992-2012

These contours represent water level change in the shallow aquifer in Lahontan Valley from 1992 - 2012 based on depth-to-groundwater measurements made in 73 wells in 1992 and 2012, with limited measurements made in 2013. Measurements collected in 2013 were used to develop the contours only in limited cases where the measurement well was being pumped or was inaccessible in 2012. Water-level change in the shallow aquifer was determined by differencing measurements made in 1992 with current measurements. The difference values were used to interpolate a change surface and contours were developed from that surface.