- Virginia Water Resources Research Center Strategic Plan 2022-2026(Virginia Tech, 2021-07-28)The VWRRC 2022-2026 Strategic Plan outlines our approach to: • Strengthen and expand programs in discovery/research, learning, and outreach/engagement; • Be widely recognized for services in water-resources discovery, learning, and engagement; • Increase representational diversity and inclusiveness; and • Develop a reliable, stable, long-term funding source and administrative support that allows the VWRRC to achieve its program goals.
- Using Single Sample Information to Evaluate Criteria for Waterbody Health RiskSmith, Eric P. (Virginia Water Resources Research Center, 2015-07)Recommendations from the U.S. Environmental Protection Agency (EPA) published in 2012 for bacteria water-quality evaluation are based on criteria using a geometric mean (GM) and a statistical threshold value (STV). If the GM calculated from water samples taken at a monitoring site exceeds the recommended GM criterion or if 10% of the samples exceed the recommended STV, then the waterbody is in violation. The recommendations indicate a minimum of four samples be used for calculations. In this report, evaluation of water quality using a single sample is statistically compared to the EPA approach for waterbodies that are in compliance and for those that are not in compliance. When the waterbody is truly in compliance with the recommended GM, the probability of a false declaration (declaring the waterbody to be in violation) for the single sample approach is below 0.5 (50%) and decreases as the true GM of the waterbody decreases. When the waterbody is truly in violation, the false declaration (saying the waterbody is in compliance), as based on a single sample, decreases from 0.5 at the GM criterion to close to zero for waterbodies with GMs that are just below the STV. When multiple samples are available, the probability of declaring a waterbody to be in violation increases as a function of sample size regardless of whether or not the waterbody is truly in violation or not. Hence there is an increase in the true declaration of a violation (when the waterbody is truly in violation) as well as in the false declaration of a violation (when the waterbody is truly in compliance). Relative to the GM approach, the single sample approach will almost always have higher error rates. The EPA approach does not involve a statistical test and error rates for GMs on or near the boundary of the decision rule. For waterbodies near the criterion, false declarations do not decline sharply as a function of sample size. When the GM is equal to the numerical criterion, the probability of declaring the waterbody as a health risk when it is not is 0.5 regardless of the sample size.
- Lessons from Florida’s Experience Developing Numeric Nutrient Standards for Flowing WatersShabman, Leonard A.; Stephenson, Stephen Kurt; Nearhoof, Frank (Virginia Water Resources Research Center, 2014-09)The December 2012 report entitled Technical and Policy Considerations and Options in Assessing Nutrient Stresses on Freshwater Streams in Virginia argued that the proposed screening process by the Academic Advisory Committee (AAC) to the Virginia Department of Environmental Quality (DEQ) was analogous to the Florida process that was then awaiting approval by the U.S. Environmental Protection Agency (EPA). In turn the report argued, “If EPA accepts the new Florida rule, the Florida approach can be referenced as a justification for the Virginia-specific screening approach.” That same 2012 AAC report reviewed a March 16, 2011 memorandum from EPA headquarters (Nancy Stoner) on nutrient criteria development by the states and argued that the memorandum was further justification for proposing the screening approach to EPA. EPA has since approved the Florida rule for numeric criteria and has proposed rulemaking that follows the Stoner memorandum (see Appendix A). Both of these actions further justify Virginia moving forward with development of the AAC proposed screening approach. This paper updates the 2012 report by expanding upon the explanation of the EPA-approved Florida process. Based on this update, the AAC again makes the argument that DEQ rely on the precedent of the Florida approval, as well as the EPA proposed rulemaking, to promote a Virginia screening approach to EPA. However, because of differences in data availability and other state-specific circumstances, there must be differences in application between Florida and Virginia, and these differences may need to be acknowledged if DEQ approaches EPA for approval of a Virginia process. DEQ might consider continuing to engage the AAC during the next year to make modifications to the draft screening approach that will align it with the Florida model as much as possible given the reality of data limitations. The process of evaluating the applicability of the EPA-approved Florida process to Virginia’s screening approach involved engaging with Frank Nearhoof, a recently retired Florida Department of Environment Protection (FDEP) staff person who was directly involved in the design of the Florida rule. Nearhoof provided two background papers (see appendices A and B) and participated in three phone calls with the authors to review the materials included in this report. For that reason, the authors believe that the description of the Florida process is accurate. One particular feature of the Florida process needs to be emphasized: If the waterbody is covered by a nutrient TMDL then that TMDL (and any implied nutrient criteria) governs the listing and the load reduction strategy for that water. The Florida process described in the next section is for those places where there is no existing TMDL limit for nutrients.
- Emerging Contaminants in the Waters of VirginiaXia, Kang (Virginia Water Resources Research Center, 2019-10)This report details the activities and findings of the Academic Advisory Committee (ACC) to the Virginia Department of Environmental Quality (DEQ) for Section 3 of the fiscal year (FY) 2019 approved scope of work. The scope of work calls for “a literature review to inform a future monitoring strategy to assess emerging contaminants in Virginia waters.” The DEQ is considering the need to expand its monitoring strategy to evaluate the presence, magnitude, risks of, and potential abatement strategies for emerging contaminants in the waters of Virginia. To initiate work towards this endeavor, the AAC conducted a literature review to address the interest expressed by DEQ in emerging contaminants in the waters of Virginia.
- A “Screening Approach” for Nutrient Criteria in VirginiaZipper, Carl E. (Virginia Water Resources Research Center, 2016-06)This report provides information on development of nutrient criteria for wadeable freshwater rivers and streams.
- Report of the Academic Advisory Committee: Developing Freshwater Nutrient Criteria for Virginia’s Streams and Rivers(Virginia Water Resources Research Center, 2010-05-25)This report is a compilation of study results and three separate AAC progress reports that address three specific objectives: wadeable streams, non-wadeable streams, and downstream loading impacts of nutrients.
- Technical And Policy Considerations And Options In Assessing Nutrient Stresses On Freshwater Streams In VirginiaZipper, Carl E.; Stephenson, Stephen Kurt; Shabman, Leonard A.; Yagow, Eugene R.; Walker, Jane L. (Virginia Water Resources Research Center, 2012-12-24)This report is prepared for the Virginia Department of Environmental Quality (DEQ) by the Academic Advisory Committee (AAC) to communicate perspectives of the Committee concerning nutrient criteria for freshwaters in the Commonwealth. The AAC has been advising DEQ on nutrient criteria development since 2003. Activities have included providing general advice and perspectives to initiate the process in 2003-2004; advising development of criteria for lakes and reservoirs, now completed; and advising on development of criteria for freshwater rivers and streams, ongoing. The AAC has proposed that nutrient criteria for freshwater wadeable rivers and streams be executed through what it calls the “Screening Approach.” In its June 2012 report, the AAC investigated the feasibility for application of the Screening Approach by deriving potential screening parameters from Virginia DEQ water monitoring data and by conducting a preliminary investigation of the resource requirements for implementation of the approach. Here, we provide Virginia DEQ with the Committee’s perspectives concerning scientific and policy issues and options related to application of the Screening Approach. This document is intended to serve as a supplement to the AAC’s 2012 report and is being provided at the request of Virginia DEQ. The focus of this document is nutrient criteria for freshwater wadeable rivers and streams (referred to as “streams” throughout the document) in Virginia’s Mountain and Piedmont regions.
- A Screening-Value Approach to Nutrient Criteria Development for Freshwater Wadeable Streams in the Mountain and Piedmont Regions of Virginia: July 2008 – June 2009 ActivitiesZipper, Carl E.; Holtzman, Golde I.; Smock, Leonard A.; Yagow, Eugene R.; Benfield, Ernest F.; Bukaveckas, Paul A.; Lung, Wu-Seng; Shabman, Leonard A.; Stephenson, Stephen Kurt; Walker, Jane L.; Younos, Tamim M. (Virginia Water Resources Research Center, 2009)This report documents activities being conducted by the Water Quality Academic Advisory Committee (AAC) to Virginia Department of Environmental Quality (DEQ) in collaboration with Virginia DEQ for the purpose of developing nutrient criteria for wadeable, freshwater rivers and streams in the Mountain and Piedmont regions of Virginia. The Mountain region of Virginia is within the following Level III Ecoregions: Central Appalachians, Ridge and Valley, and Blue Ridge. The Piedmont region of Virginia is within the following Level III Ecoregions: Northern Piedmont and Piedmont.
- December 2006 Report Of The Academic Advisory Committee To Virginia Department Of Environmental Quality: Freshwater Nutrient Criteria For Rivers And StreamsZipper, Carl E.; Yagow, Eugene R.; Walker, Jane L.; Smith, Eric P.; Shabman, Leonard A.; Smock, Leonard A.; Hershner, Carl H.; Younos, Tamim M.; Benfield, Ernest F.; Bukaveckas, Paul A.; Garman, Greg C.; Kator, Howard I.; Lung, Wu-Seng; Stephenson, Stephen Kurt (Virginia Water Resources Research Center, 2007-01-10)This report reviews activities conducted by the Academic Advisory Committee to the Virginia Department of Environmental Quality (DEQ) between July and December 2006. Activities were conducted for the purpose of developing recommendations for DEQ regarding nutrient criteria for freshwater rivers and streams.
- Virginia Water Resources Research Center Strategic Plan 2017-2021(Virginia Tech, 2017-02-15)
The VWRRC 2017-2021 Strategic Plan outlines our approach to:
- Be widely recognized as a resource for credible water resources information and a widely recognized center in areas of discovery, learning, and engagement in the U.S.;
- Facilitate innovative approaches to solving water resources challenges; and
- Develop a reliable, stable, long-term funding source that allows the VWRRC to achieve its goals.
- A Guide to National Drinking Water Standards and Private Water Systems(Virginia Water Resources Research Center, 1996)
- A Guide to Protecting Virginia's Valuable Resource: Ground WaterPoff, Judy A. (Virginia Water Resources Research Center, 1997)
- Groundwater Research : The Front Line of Defense For a Resource Under Siege : Water Institutes research programKroehler, Carolyn J.; Crumbley, Elizabeth B. (Virginia Water Resources Research Center, 1990)
- A Homeowner's Guide to the Development, Maintenance, and Protection of Springs as a Drinking Water Source(Virginia Water Resources Research Center, 1999)
- Virginia's water resources : policy and management issuesCox, William E.; Shabman, Leonard A.; Batie, Sandra S.; Looney, J. W. (Departments of Agricultural Economics and Civil Engineering, Virginia Tech, 1981-07-15)