TDS Trends in the Monongahela River Basin: 2009-2022
A story of water quality improvements in the Monongahela River and key tributaries shown through 3RQ monitoring data.
Background
The Monongahela River Basin
The Monongahela River, or “the Mon,” begins in mountainous West Virginia at the convergence of the West Fork and Tygart Valley Rivers. It then journeys northward through Morgantown, WV, and the historic steel-making corridor of Pennsylvania to downtown Pittsburgh, where it joins the Allegheny River to form the Ohio River. Downstream, the Ohio River empties into the Mississippi River and, ultimately, the Gulf of Mexico.
Nine locks and dams make the 130-mile-long Mon River navigable year-round. The river drains a total of 7,340 square miles within Pennsylvania, West Virginia, and Maryland and serves as the source of drinking water for approximately one million people. Visit this EPA site to learn more about your drinking water.
The map to the right shows the geographic extent of the Monongahela River Basin, its tributaries, and demographic information [1].
Industrialization and the Monongahela River
In the 1890s, the river was a gateway to industrialization, providing the water necessary for industrial use and barge transportation. This drove the growth of the cities and towns along the river, but also caused widespread pollution. As a result of over 200 years of coal mining in the region, the Mon and many of its tributaries were considered biologically dead due to degradation by acidity and metals primarily from abandoned mines [2]. In the mid-1960s, fish surveys on the Monongahela River found zero to four fish species per sampling site [3].
Active and abandoned coal mines in the region are shown on the map to the right [4] [5] [6] [7].
The river has significantly transformed since then thanks to legislation such as the Clean Water Act of 1972. By 2010, it had improved to supporting over 70 fish species, including much improved sauger and smallmouth bass fisheries [8]. However, the Mon was still experiencing impacts of ongoing coal mining, natural gas extraction, and legacy pollution.
The map to the right shows the location of historic and active oil and gas wells [9] [10] [11]. Press play to see the development of the industry over time (it may take a moment to load).
Total Dissolved Solids Issues Arise
In the summer of 2008, sulfate and total dissolved solids (TDS) levels in the Monongahela River were nearly twice as high as those documented prior to the Clean Water Act [12]. These high levels affected public drinking water supplies and industrial users along the river due to pipe corrosion, scaling, taste, and odor problems [13].
Further attention to the elevated TDS values came in 2009 when a major fish kill occurred in Dunkard Creek, a tributary to the Mon, largely due to elevated salinity. Over 40,000 fish of 40 species died during the kill, as well as mudpuppies and freshwater mussels [14]. The extent to which that could be attributed to the mining or oil and gas industries was unknown. In response, the West Virginia Water Research Institute (WVWRI) initiated a monitoring program within the Monongahela River Basin in 2009 to investigate the source of the TDS issue.
Developing Solutions
Voluntary, Coordinated Management of Active Mine Discharges
Resultant data showed that treated mine drainage, rich in calcium, sodium, and sulfate, was the controlling factor in the Monongahela River’s TDS load [15]. Conditions worsened during periods of low flow during summer and early fall. WVWRI began working with major coal companies along the Upper Mon River Basin to develop a model to manage active deep coal mine discharges.
The resultant model coordinates the outflows of fourteen major mine pumping and treatment plants with the flow of the Monongahela River on any given day. The model also utilizes typical TDS concentrations in the Monongahela and is set to not exceed the Safe Drinking Water Act (SDWA) standard of 500 mg/L of TDS, with a safety factor of 2. In 2010, the coal industry voluntarily implemented the model to determine appropriate plant pumping rates. The voluntary discharge management plan (VDMP) was developed and implemented more quickly than regulatory measures could be, thus providing an immediate and cost-effective solution to the Monongahela River’s TDS issue.
Birth of the Three Rivers QUEST Program
Monongahela River monitoring has continued to track TDS trends and inform the VDMP since 2009. Today, the monitoring program is known as Three Rivers QUEST (3RQ), with the addition of university partners in the Allegheny and Ohio Rivers (Duquesne and West Liberty Universities, respectively) and the integration of outside watershed-based group data. All data is available to view through the 3RQ Mapping Hub .
Monitoring Methods
3RQ monitors 18 sites in the Monongahela River Basin, including six sites on the mainstem of the Mon River and 12 near the mouths of major tributaries. Water samples and field readings are collected monthly by WVWRI staff. Field readings include water temperature, pH, TDS, and conductivity. River discharge is either directly taken from a USGS gage or calculated depending on the site location. Samples are analyzed by a commercial analytical laboratory for concentrations of the following parameters:
- Dissolved alkalinity
- Aluminum
- Barium
- Calcium
- Iron
- Manganese
- Magnesium
- Strontium
- Sodium
- Bromide
- Chloride
- Sulfate
- TDS
Results
Water Quality Improvements in the Monongahela
The 3RQ monitoring program provides a valuable understanding of how the Mon River has changed over time and in relation to management decisions. The relationship between TDS and river discharge at mainstem sites is shown in the figure to the right. As expected, higher TDS concentrations are seen during late summer and fall when rivers experience low flows. TDS displays a long-term decrease, regardless of discharge, following the implementation of the voluntary discharge management plan [16]. Since applying the plan, TDS and sulfate values have not exceeded the SDWA standards of 500 and 250 mg/L, respectively, at mainstem sampling locations.
Tributary Trends
TDS remains highly variable within Monongahela River tributaries. To view TDS trends for each site, click on a point in the map then click to enlarge the figure in the popup.
Analysis shows significant decreases in TDS and sulfate concentrations in Dunkard Creek and Flaggy Meadows Run. Improvements seen are a cumulative effort of several management improvements, including implementing the VDMP. Several tributaries, including Flaggy Meadows Run, Robinson Run, Whiteley Creek, and Indian Creek, still consistently display TDS and sulfate concentrations above the SDWA standards. Other major tributaries, such as the Tygart Valley and Cheat Rivers, have consistently low TDS levels, thus reducing vulnerability in the receiving Monongahela River.
Discussion
The overall water quality of the Monongahela River has continuously improved since the 1960s. Just within the past decade, 3RQ data shows declines in TDS and sulfate. Several key management changes, including the VDMP for active mine discharges, have led to these changes.
An early testament to the improvements and gaining interest in the quality of the Mon River came with its award as the “ River of the Year ” in 2013, demonstrating progress in transforming the watershed into a cultural asset. Then, in 2014, the Environmental Protection Agency removed the Mon from the list of impaired rivers, concluding that the river’s in-stream TDS and sulfate concentrations now met the state water quality standards. Data collected through 3RQ was provided to the PADEP to evaluate sulfate contamination levels to aid in this determination [17].
Today, multiple task forces and programs, such as Mon River Towns and the Morgantown Riverfront Revitalization Task Force , focus on utilizing the river's cultural and recreational economic benefits while raising awareness to continue to protect and restore the river. The river's health depends on the local economy's health, and vice versa. Examples of recreational opportunities in the watershed are shown in the map to the right [18].
Long-term water quality monitoring programs like 3RQ enable resource managers to characterize trends in water quality over time, identify pollution sources, and provide timely alerts to emerging water quality problems. The VDMP for active coal mine discharges is just one example of the application of 3RQ data for identifying, managing, and evaluating a pollution issue. Baseline water quality data can also provide information on the effects of new or increased industry or disasters such as chemical spills.
To ensure continued improvements in the Monongahela River Basin, it is imperative that the VDMP continue to be implemented, especially during drought periods, which are expected to increase due to climate change [19]. Drought conditions reduce the river’s assimilative capacity, causing pollutants to become more concentrated.
Climate change has already begun increasing the number of extreme weather events like droughts and storms, which impacts streamflow and affects water quality [20]. Other influences, such as industry, development, and land use changes could also impact stream conditions. With changing climate and land use, 3RQ must continue monitoring water quality and communicating with river stakeholders to ensure continued improvements in the Monongahela River Basin.
Conclusion
3RQ data shows that the Monongahela River has improved in both TDS and sulfate concentrations since the initiation of the VDMP in 2010. Monongahela River tributaries remain highly variable in their TDS values, with Dunkard Creek and Flaggy Meadows Run displaying the most noteworthy improvements during the study period.
3RQ has amassed a dataset that proves valuable for evaluating long-term trends, establishing baseline conditions, and providing early alerts to arising issues. Additionally, 3RQ maintains a network of local stewards, university researchers, regulatory professionals, and industry partners devoted to collaboratively solving problems as they arise. Long-term water quality monitoring programs like 3RQ must continue to receive support so that water managers can make informed decisions on water quality issues.
Dive Deeper into 3RQ Data
- Utilize our 3RQ Mapping Tool to view 3RQ and watershed group data, as well as additional informative layers from state and federal agencies, and more.
- Explore our Map Hub page which includes even more maps, including story maps of Targeted Studies in the Upper Ohio River Basin.
- Read the open-source article, Effective Management Changes to Reduce Halogens, Sulfate, and TDS in the Monongahela River Basin, 2009–2019 .
References
[1] U.S. Bureau of the Census. TIGER/Line: USA 2020 Census Population Characteristics. Washington D.C.: Bureau of the Census, 2020.
[2] Sams, J. I. & Beer, K. M. Effects of coal-mine drainage on stream water quality in the Allegheny and Monongahela River Basins-Sulfate transport and trends. (2000). U.S. Geological Survey. Lemoyne, Pennsylvania. https://doi.org/10.3133/wri994208
[3] U.S. Army Corps of Engineers, 1976, Monongahela River navigation projects, annual water quality report, 1976: Pittsburgh, Pa., 106 p.
[4] U.S. Energy Information Administration. Coal Mines. Washington D.C.: U.S. Energy Information Administration, 2023.
[5] Pennsylvania Department of Environmental Protection. AML Polygons Feature. RCSOB: Pennsylvania Department of Environmental Protection, 2023.
[6] The Maryland Department of the Environment, Land Management Administration, Mining Program (MDE), and the Maryland Environmental Service. Maryland Historical Mining. Frostburg, MD: MDE, 2018.
[7] WV Department of Environmental Protection. Mining – Abandoned Mine Lands. Charleston, WV: WVDEP, 1996.
[8] Kinsey, M. and Ventorini, B. 2010. Monitoring Fishes of the Monongahela River. Commonwealth of Pennsylvania, Fish and Boat Commission. https://pfbc.pa.gov/images/reports/2010bio/8x07_13mon.htm. Accessed 16 August 2023 .
[9]Maryland Department of Environment. MD-06292017. Frostburg, MD: Maryland Department of Environment, 2017.
[10] The West Virginia Department of Environmental Protection. WVDEP Oil & Gas Data. Charleston, WV: WVDEP, 2023.
[11] Pennsylvania Department of Environmental Protection. Oil & Gas Locations – Conventional Unconventional. Harrisburg, PA: PADEP, 2023.
[12] PADEP. (2008). DEP Investigates Source of Elevated Total Dissolved Solids in Monongahela River. Harrisburg: Commonwealth of Pennsylvania. Retrieved July 25, 2023, from https://s3.amazonaws.com/propublica/assets/monongahela/10.22.08PADEPPressReleaseonTDSInvestigation.pdf
[13] Wilson, J. M., & Van Briesen, J. M. (2013). Source Water Changes and Energy Extraction Activities in the Monongahela River, 2009–2012. Environmental Science & Technology, 47(21), 12575–12582. https://doi.org/10.1021/es402437n
[14] Urban, C. Dunkard Creek Aquatic Life Kill Re-Assessment; Pennsylvania Fish & Boat Commission, Division of Environmental Services, Natural Diversity Section: Corry, PA, USA, 2016; p. 41.
[15] Merriam, E. R., Petty, J. T., O'Neal, M., & Ziemkiewicz, P. F. (2020). Flow-Mediated Vulnerability of Source Waters to Elecated TDS in an Appalachian River Basin. Water, 12(2). doi:https://doi.org/10.3390/w12020384
[16] Kingsbury, J. W., Spirnak, R., O’Neal, M., & Ziemkiewicz, P. (2023). Effective Management Changes to Reduce Halogens, Sulfate, and TDS in the Monongahela River Basin, 2009–2019. Water, 15(4), 631. https://doi.org/10.3390/w15040631OR
[17] PADEP. (2014). 2014 Pennsylvania Integrated Water Quality Monitoring and Assessment Report. https://www.pennfuture.org/Files/Publications/2014_Pennsylvania_Integrated_Water_Quality_Monitoring_and_Assessment_Report.pdf
[18] Strager, J. Master Trails dataset for WV (NRAC version). Morgantown, WV: J. Strager, 2020.
[19] Hoegh-Guldberg, O., Jacob, D., Taylor, M., Bindi, M., Brown, S., Camilloni, I., . . . Zhou, G. (2018). Chapter 3: Impacts of 1.5 degree C global warming on natural and human systems. Cambringe: Cambridge University Press. doi:doi:10.1017/9781009157940.005. [MS1]
[20] US EPA. (2016, July 1). Climate Change Indicators: Streamflow. https://www.epa.gov/climate-indicators/climate-change-indicators-streamflow
Acknowledgements
This project was supported by the United States Geological Survey. Funding for the 3RQ program is provided by The Colcom Foundation and the Foundation for Pennsylvania Watersheds.
