In Nevada irrigation is an essential component of agriculture. In addition due to limited water supplies irrigation water is often returned to surface waters that are used for fisheries, recreation, and human and wildlife consumption. In many western watersheds due to the geologic setting and legacy mining mercury occurs in soils. In addition there are fish consumption advisories in western watersheds for mercury where there are no clear terrestrial sources of mercury and mercury inputs are thought to be derived from the atmosphere.
With population increasing in the west, agriculture and recreation could greatly impact the economies of rural areas in Nevada. By understanding the impact drainage from irrigation has on the water system, mitigation can be more effective resulting in fisheries, hunting grounds, and recreational areas that support healthy wildlife populations that are safe for human consumption. Water will continue to be a critical need and the more we understand water contamination problems the more tools we’ll have to manage and promote healthy resources for people and wildlife.
This study will evaluate the potential for delivery of mercury and methyl mercury from irrigation drainage ditches into receiving water bodies. The results will help managers determine the role, if any, irrigation drainage ditches play in conveying mercury into surface waters and the potential for these areas to be sites of conversion of inorganic mercury into the biologically harmful methyl mercury and what physical features, soil conditions, water chemistry, or biological communities encourage this transformation.