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Source Water Protection (SWP)

Research and Reports on Source Water Protection

On this page:

EPA Resources

  • The Influence of Green Infrastructure Practices on Groundwater Quality: The State of the Science (2018) - The goal of this literature review is to provide the current understanding of potential impacts or impacts to groundwater quality that could result from the use of green infrastructure to manage stormwater runoff.
  • Economic Support for Source Water Protection Decisions - With growing interest in source water protection (SWP) as a means to avoiding expenditures at drinking water treatment plants, it is increasingly important to understand the costs and potential benefits of better watershed management. This paper, which is an invited feature article for the Journal American Water Works Association, describes the role economics has in estimating avoided treatment costs and determining whether SWP is a cost-effective.
  • The Effects of Source Water Quality on Drinking Water Treatment Costs: A Review and Synthesis of Empirical Literature - With concerns about drinking water quality and safety expanding, in part, due to excess watershed nutrient loadings, it is becoming increasingly important to understand the associated costs and potential benefits of better watershed management for drinking water treatment plants (DWTPs). This paper reviews existing literature estimating the relationship between source water quality and drinking water treatment costs. By completing this research activity, we hope to improve our understanding of the relationship between measures of water quality and drinking water treatment costs.
  • Comparing Drinking Water Treatment Costs to Source Water Protection Costs Using Time Series Analysis - The motivation for the study is to determine whether a drinking water treatment plant (DWTP) would have incentive to participate in a water quality trading program as a demander for pollution reduction credits from agricultural producers. In addition, the analysis provides decision support for the DWTP to invest in source water protection and conservation in the form of comparing drinking water treatment costs to source water protection costs. 
  • Modeled De Facto Reuse and Contaminants of Emerging Concern in Drinking Water Source Waters - The purpose of this paper is to look at a source water data set through the lens of de facto reuse to see if there is a relation between chemical detections and percent wastewater in source water.
  • Per-and Polyfluoroalkyl Substances in Source and Treated Drinking Waters of the United States - This is the last paper in the series describing the results of a USEPA/ USGS collaboration examining 247 contaminants of emerging concern (CECs) in source and treated drinking water from 25 drinking water treatment plants (DWTPs). Samples were collected from 2010-2012. The frequencies of detections and the maximum detections were previously published in Glassmeyer et al 2017. This paper goes into a detailed discussion on the per- and polyfluoroalkyl Substances (PFAS) detections at each DWTP. This dataset in particular provides PFAS data at concentrations below that available in the third round of the Unregulated Contaminant Monitoring Rule (UCMR 3) sampling, as well as for more PFAS compounds (17 versus 6), which will be useful in future health advisory determinations.

Other Federal Resources 

United States Geological Survey

  • Factors Affecting Vulnerability of Public-Supply Wells to Contamination - Public-supply wells can be vulnerable to contamination from naturally occurring constituents, such as radon, uranium and arsenic, and from commonly used manmade chemicals, such as fertilizers, pesticides, solvents, and gasoline hydrocarbons. Learn about the Transport of Anthropogenic and Naturally Occurring Contaminants (TANC) study.
    • Factors Affecting Public-Supply-Well Vulnerability to Contamination: Understanding Observed Water Quality and Anticipating Future Water Quality (USGS Circular 1385) - As part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program, a study was conducted from 2001 to 2011 to shed light on factors that affect the vulnerability of water from public-supply wells to contamination
    • Geochemical conditions - Information on the geochemical conditions encountered by groundwater traveling to a well provides insight into contaminants that might persist in the water all the way to the well. Use the Redox Framework Tool to determine the redox conditions associated with water from a public-supply well.
    • Groundwater-age mixtures - Information on the ages of the different waters that mix in a well provides insight into the time lag between contaminant input at the water table and contaminant arrival at the well. It also provides insight into the potential for in-well dilution of contaminated water by unaffected groundwater of a different age that simultaneously enters the well. Use the web-based Groundwater Age Mixtures and Contaminant Trends Tool to explore the effects of basic aquifer properties and well configurations on groundwater age mixtures in groundwater discharge and on contaminant trends from different nonpoint-source contaminant input scenarios.
  • Cyanobacterial Harmful Algal Blooms and U.S. Geological Survey Science Capabilities - U.S. Geological Survey (USGS) scientists are leading a diverse range of studies to address CyanoHAB issues in water bodies throughout the United States, using a combination of traditional methods and emerging technologies, and in collaboration with numerous partners. By providing practical applications of cutting edge CyanoHAB research, USGS studies have advanced scientific understanding, enabling the development of approaches to help protect ecological and human health.

United States Forest Service

  • Forests to Faucets - The U.S. Department of Agriculture (USDA) Forest Service Forests to Faucets project uses GIS to model and map the continental United States land areas most important to surface drinking water, the role forests play in protecting these areas, and the extent to which these forests are threatened by development, insects and disease, and wildland fire.
    • Forests, Water and People: Drinking water supply and forest lands in the Northeast and Midwest United States (2009) - Protecting and managing forests in source watersheds is an essential part of future strategies for providing clean, safe drinking water that citizens can afford. This analysis uses a GIS-based process and a series of maps to create a watershed condition index based on physical and biological attributes. Using a multi-step process, this index is then used to compare 540 watersheds across 20 States and the District of Columbia, in terms of their ability to produce clean water. The study also quantifies the magnitude and scope of forest-dependent drinking water supplies, and their dependence on private forests; and it identifies watersheds that are threatened by land use change or are in need of management to sustain and improve forests that protect water supplies. The final maps and data display development pressure on private forests in watersheds important for drinking water.