Nebraska Vadose Zone program aims to protect water quality in the long-term
The vadose zone is the interval between the crop root zone and the water table, and is a critically important region for storage, transport and transformation of chemicals that can impact groundwater quality. The new Nebraska Water Center video above provides an overview of the Nebraska Vadose Zone program, which standardizes collection, processing, analysis, and sharing of vadose zone monitoring data, with the goal of protecting water quality in the long-term.
In Nebraska, most of the population relies on ground water for drinking. Unfortunately, nitrate concentrations in ground water in many parts of the state are rising. In addition, some pesticides, as well as uranium and other metals may be increasing across the state. While state and local agencies have conducted regular ground water monitoring, more work is needed to characterize the vadose (unsaturated) zone. Contaminants present in the vadose zone can eventually appear in the underlying aquifers.
To protect public health, the Environmental Protection Agency (EPA) regulates certain contaminants, including nitrate, through the National Primary Drinking Water Regulations (NPDWR). If contaminants are found in public water systems in excess of legally enforceable Maximum Contaminant Levels (MCLs), a utility must either treat the water or find an alternate supply. Thus, natural resources managers, city planners, treatment plant operators, regulators, researchers, and others have an interest in monitoring the vadose zone to anticipate if and when contaminants will reach the groundwater supply, and in what amount.
Coordination is still needed to monitor and model contaminants occurrence and movement across the vadose zone, which can be hundreds of feet thick. State and local entities may use the Nebraska Vadose Zone program's public database to make decisions and prepare for future changes in water quality.