Grantee Research Project Results
2018 Progress Report: Improving Water Reuse for a Much Healthier Potomac Watershed
EPA Grant Number: R835825Title: Improving Water Reuse for a Much Healthier Potomac Watershed
Investigators: Olabode, Lola , Kaushal, Sujay S , Aga, Diana S. , Godrej, Adil , Rosenfeldt, Erik , Mattingly, Justin , Iwanowicz, Luke
Current Investigators: Olabode, Lola , Olabode, Lola , Aga, Diana S. , Kaushal, Sujay S , Duan, Shuiwang , Godrej, Adil , Iwanowicz, Luke , Rosenfeldt, Erik , Murthy, Sudhir
Institution: Water Research Foundation , Virginia Tech , Hazen and Sawyer , United States Geological Survey , University of Maryland - College Park , University of Buffalo
Current Institution: Water Research Foundation , University of Maryland - College Park , Virginia Tech , University of Buffalo , United States Geological Survey , Hazen and Sawyer , District of Columbia Water and Sewer Authority (DC Water)
EPA Project Officer: Packard, Benjamin H
Project Period: November 1, 2015 through November 1, 2018 (Extended to November 1, 2020)
Project Period Covered by this Report: November 1, 2017 through October 31,2018
Project Amount: $750,000
RFA: Human and Ecological Health Impacts Associated with Water Reuse and Conservation Practices (2014) RFA Text | Recipients Lists
Research Category: Water , Human Health
Objective:
The purpose of this study is to elucidate the impact of advanced wastewater reclamation, large scale stormwater harvesting and reuse, and focused agricultural stormwater best management practices on their impact on ecological and human health in a large ecologically sensitive watershed that is critical for human health. The novel approach undertaken in this research combines a suite of state-of-the-art techniques to actively identify contaminant hot spots (EDCs and related biological activity, nutrients), assess the impact of those hot spots on human and ecological health endpoints (including drinking water sources and sensitive ecological areas), and quantify the impact of reuse and management solutions on these endpoints. Further, this project will compare the findings from both planned and unplanned reuse systems in order to quantify relative impacts between the two types of systems. This approach will ultimately provide a tool for decision makers to prioritize actions taken to manage contaminant sources and implement water reuse and management practices to better determine where funds and other resources can be best used, are most needed, and are most likely to achieve success. Specifically, this project will 1) use multiple analytical, biological activity, isotopic, and fluorescence tracers to identify and track spatial and temporal variability in "hot spots" of contaminant sources at a large watershed scale, 2) use case studies to examine impacts of advanced wastewater reclamation, stormwater reuse, and agricultural best management practices on source controls of contaminants, and 3) utilize a sustainable approach to quantitatively analyze the costs, impact, and benefits of the reuse and management strategies for achieving human and ecological health improvement.
Progress Summary:
The objectives of this project for the second year includes two parts:
1. Use paired watershed studies to evaluate impacts and outcomes of current reclamation, reuse, harvesting, and management strategies on source controls of pollutants.
2. Focused study on the comparative impact of planned potable reuse.
Chemical analysis: The research team has almost finished our sample chemical analysis including total dissolved nitrogen, dissolved inorganic carbon, dissolved organic carbon, fluorescence scan, and EDCs - estrogens and pesticides. The phosphorus analysis has not finished yet due to complications with the instruments, but will be completed in early 2019.
Flow data and mass balances: The Washington Suburban Sanitary Commission (WSSC) provided flow data for the Seneca wastewater treatment plant (WWTP), and the data were used to calculate daily fluxes of nutrients and endocrine disrupting compounds (EDCs). Stream flows of the Seneca Creek near the WWTP are not available, because United States Geological Survey (USGS) gauges of the Seneca Creek are too far away from the facility. Instead, the research team is looking to use conductivity to estimate the Seneca Creek stream flow to complete the mass balances of nutrients and EDCs. Mass balances of nutrients and EDCs for the Bull Run and the Upper Occoquan Service Authority (UOSA) were completed last quarter, and the results are included in this report for comparison to Seneca Creek.
Preliminary results have showed the following findings:
Agricultural streams with best management practices (BMPs) were generally lower in total dissolved nitrogen (TDN), estrogen and pesticides (e.g., atrazine, prometon, metolachlor, and simazine), suggesting agricultural BMPs can result in the retention of nutrients and EDCs. Such retention was not found with urban BMPs;
Discharge of UOSA effluent resulted in downstream increases in TDN in the Bull Run, however is a normal operational condition unique to UOSA and the Occoquan system. Higher discharges of nitrate are allowed to prevent the release of undesirable constituents such as phosphorus, iron, manganese and ammonia from Reservoir sediments. Effects of UOSA effluent discharge on downstream pesticide varied with flow conditions. During a storm event in May, discharge of UOSA effluent caused downstream decreases in these pesticides. During other flow periods, discharge of UOSA effluent caused downstream increases in these pesticides.
TDN inputs from the Seneca WWTP and Seneca Creek were comparable during low-flow period - October to February, but TDN inputs from Seneca Creek showed larger seasonality differences and tripled during high-flow period. TDN retention or release in this stream section was minor relative to inputs from the WWTP or stream sources. In contrast, TDN inputs from UOSA were higher than inputs from the Bull Run with one exception of the May storm event. Larger fraction of TDN from UOSA was retained within the Bull, due to longer length of the sampled stream section.
Soluble reactive phosphorus (SRP) inputs from the Seneca WWTP or UOSA were generally much higher than SRP inputs from Seneca Creek or Bull Run (one exception). More SRP inputs from UOSA were retained within the stream section (except May storm event) relative to that in Seneca Creek due to longer length of stream section in this stream.
Fluxes of some EDCs (Atrazine, Metolachlor and Simazine) in Seneca Creek and all EDCs in Bull Run were much higher in the May storm event than any other month. During this period, the inputs from the Seneca WWTP were comparable to (or even higher than) the inputs from Seneca Creek. In Bull Run, inputs of all EDCs from the stream were dominant during the storm event. In contrast, inputs of non-estrogen EDCs from the UOSA were higher during the low-flow period of October to April.
Future Activities:
In the subsequent reporting period, the project team will complete the phosphorous analysis, collect wastewater effluent flow data for the Blue Plains WWTP, and conduct mass balance for the Potomac River with the wastewater effluent flow data. During this time, the quantitative cost benefit and impact assessment will also be completed.
Journal Articles:
No journal articles submitted with this report: View all 18 publications for this projectProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.