scholarly journals Localized Water Quality Improvement in the Choptank Estuary, a Tributary of Chesapeake Bay

2021 ◽  
Author(s):  
Thomas R. Fisher ◽  
Rebecca J. Fox ◽  
Anne B. Gustafson ◽  
Erika Koontz ◽  
Michelle Lepori-Bui ◽  
...  
Keyword(s):  
Water Quality ◽  
Wastewater Treatment ◽  
Atmospheric Deposition ◽  
Chesapeake Bay ◽  
Agricultural Sector ◽  
Wastewater Treatment Plants ◽  
Nutrient Budget ◽  
Point Sources ◽  
Diffuse Sources ◽  
The Usa

AbstractChesapeake Bay has a long history of nutrient pollution resulting in degraded water quality. However, we report improvements in chlorophyll a in surface waters and dissolved oxygen in bottom waters at one of three estuarine stations in the Choptank tributary of Chesapeake Bay. We updated a previous nutrient budget for the estuary constructed for reference year 1998 using rates of atmospheric deposition, inputs of watershed diffuse sources (primarily agriculture), and discharges of point sources (primarily human waste) for reference year 2017. Parallel trends suggest that improvements in water quality at the one station were likely due to 20% reductions in direct atmospheric deposition on the estuary’s surface and 78–95% reductions in wastewater N and P due to installation of tertiary treatment. The agricultural sector, the dominant source of N and P, appeared to provide little contribution to improved water quality during this period. Although efforts to reduce nutrient losses from agriculture are common throughout the Choptank basin, widespread reductions from agricultural diffuse sources could make large contributions to improved water quality at all stations in the estuary. The response in the Choptank is similar to those observed elsewhere in the USA, Europe, Australia, and New Zealand due to improved wastewater treatment. Similar to our findings, the upper Potomac River of Chesapeake Bay saw improvements driven by reductions in atmospheric deposition. Unfortunately, few studies elsewhere have shown improvements in water quality due to agricultural management. The data presented here indicate that public and industrial investments in reductions of atmospheric emissions and upgrades to wastewater treatment plants have improved estuarine water quality in the Choptank.

Cross Media Inputs to Eastern US Watersheds and Their Significance to Estuarine Water Quality

1992 ◽  
Vol 26 (12) ◽  
pp. 2675-2683 ◽  
Author(s):  
D. L. Correll ◽  
T. E. Jordan ◽  
D. E. Weller
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Atmospheric Deposition ◽  
Ground Water ◽  
Chesapeake Bay ◽  
Drainage Basin ◽  
Point Sources ◽  
Estuarine Water ◽  
Buffer Zones ◽  
Estuarine Water Quality

Extensive research on Chesapeake Bay estuary, its drainage basin, and its airshed have now demonstrated that atmospheric deposition and diffuse land discharges are the largest sources for many parameters affecting estuarine water quality. For example, phosphorus and sediments are transported to the Bay largely in overland storm flows, nitrate largely in atmospheric deposition and in ground water, many pesticides and other toxic materials in surface waters and atmospheric deposition, and silicate primarily in ground water. Concerns over point sources such as sewage treatment outfalls and industrial outfalls have led to greatly improved treatment methods, alleviating the relative magnitude of these sources. The realization of the magnitude and importance of diffuse sources has led to research on improved land use practices, including better patterns of land use in the Chesapeake Bay landscape. One example is the use of and improved management of forested riparian buffer zones in the coastal plain part of the drainage basin.

A study about the use of chemicals in conventional tertiary treatment. Performances comparison of three municipal wastewater treatment plants and pilot plant experiences

2011 ◽  
Vol 6 (1) ◽  
Author(s):  
A. Iborra-Clar ◽  
J.A. Mendoza-Roca ◽  
A. Bes-Pií ◽  
J.J. Morenilla-Martínez ◽  
I. Bernácer-Bonora ◽  
...  
Keyword(s):  
Water Quality ◽  
Wastewater Treatment ◽  
Pilot Plant ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Secondary Effluent ◽  
Municipal Wastewater Treatment ◽  
Wastewater Reclamation ◽  
Valencian Region ◽  
Municipal Wastewater Treatment Plants

Rainfall diminution in the last years has entailed water scarcity in plenty of European regions, especially in Mediterranean areas. As a consequence, regional water authorities have enhanced wastewater reclamation and reuse. Thus, the implementation of tertiary treatments has become of paramount importance in the municipal wastewater treatment plants (WWTP) of Valencian Region (Spain). Conventional tertiary treatments consist of a physico-chemical treatment of the secondary effluent followed by sand filtration and UV radiation. However, the addition of coagulants and flocculants sometimes does not contribute significantly in the final water quality. In this work, results of 20-months operation of three WWTP in Valencian Region with different tertiary treatments (two without chemicals addition and another with chemicals addition) are discussed. Besides, experiments with a 2 m3/h pilot plant located in the WWTP Quart-Benager in Valencia were performed in order to evaluate with the same secondary effluent the effect of the chemicals addition on the final water quality. Results showed that the addition of chemicals did not improve the final water quality significantly. These results were observed both comparing the three full scale plants and in the pilot plant operation.

Usacerl's Experiences with Small Wastewater Treatment Plants in the USA

1990 ◽  
Vol 22 (3-4) ◽  
pp. 49-56
Author(s):  
E. D. Smith ◽  
R. J. Scholze
Keyword(s):  
Wastewater Treatment ◽  
Waste Treatment ◽  
Wastewater Treatment Plants ◽  
Remote Site ◽  
Corps Of Engineers ◽  
Military Installations ◽  
Recreation Areas ◽  
The Usa ◽  
Rotating Biological Contactors ◽  
The U.S

This paper presents a review of collected experience of one of the U.S. Corps of Engineers research laboratories in the area of small systems for wastewater treatment. Findings and experiences are presented for the use of package plants such as rotating biological contactors (RBCs), and remote site waste treatment at military installations and recreation areas.

Sources and transport of phosphorus in the Vltava river basin (Czech Republic)

1996 ◽  
Vol 33 (4-5) ◽  
pp. 137-144 ◽  
Author(s):  
Josef Hejzlar ◽  
Vojtech Vyhnálek ◽  
Jirí Kopácek ◽  
Jirí Duras
Keyword(s):  
Czech Republic ◽  
Population Density ◽  
Atmospheric Deposition ◽  
River Basin ◽  
Point Sources ◽  
Diffuse Sources ◽  
River Elbe ◽  
Municipal Wastewaters ◽  
Total P

Export and sources of P in the Vltava basin (subbasin of upper Elbe: total area – 28,093 km2; population density – 115 km−2; forests – 35%, farmland – 51%) were evaluated during 1972–1993. Annual export rates of total P from the basin to the river Elbe ranged between 38 and 68 kg km−2 a−1. Reservoirs with hydraulic retention times longer than 15 days were efficient traps for phosphorus retaining 20 to 30% of total P loading into the watercourses. Point sources (municipal wastewaters) were most important throughout the period and their share varied from approximately 60% in wet years to more than 90% in dry years. Export from diffuse sources (dominated by output from farmland) was highly dependent on discharge and fluctuaded between 5 and 40 kg km−2 a−1 in dry and wet years, respectively. Only about 2% of the P input into the basin from the fertilisation of farmland and from the atmospheric deposition was exported to the watercourses.

scholarly journals The role of wastewater treatment plants in surface water contamination by plastic pollutants

2018 ◽  
Vol 45 ◽  
pp. 00054 ◽  
Author(s):  
Bozena Mrowiec
Keyword(s):  
Wastewater Treatment ◽  
Surface Water ◽  
Water Contamination ◽  
Membrane Filtration ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Point Sources ◽  
Municipal Sewage ◽  
Municipal Wastewater Treatment ◽  
Surface Water Contamination

The aim of this paper was to review the literature data regarding the physico-chemical characteristic of plastic pollutants discharged with municipal sewage, the practical possibility of removing microplastic particles from wastewater during different treatment steps in WWTPs and the problem of surface water contamination within them. Microplastics (the size range of 1 nm to < 5 mm), have been recognized as an emerging threat, as well as an ecotoxicological and ecological risk for water ecosystems. Municipal wastewater treatment plants (WWTPs) are mentioned as the main point sources of microplastics in an aquatic environment. Microplastic particles can be effectively removed in the primary treatment zones via solids skimming and sludge settling processes. Different tertiary treatment processes such as: gravity sand filtration, discfilter, air flotation and membrane filtration provide substantial additional removal of microplastics, and the efficiency of wastewater treatment process can be at a removal level of 99.9%. Nevertheless, given the large volumes of effluent constantly discharged to receivers, even tertiary level WWTPs may constitute a considerable source of microplastics in the surface water.

Microplastics from the Sources to Sinks: Assessment of Microplastics in the River Freshwater Environments and Wastewater Treatment Plants

2021 ◽  
Author(s):  
A H M Enamul Kabir ◽  
Masahiko Sekine ◽  
Tsuyoshi Imai ◽  
Koichi Yamamoto ◽  
Ariyo Kanno ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Point Source ◽  
Pollution Control ◽  
Wastewater Treatment Plants ◽  
Management Strategies ◽  
Freshwater Ecosystems ◽  
Point Sources ◽  
Source To Sink ◽  
Comprehensive Knowledge ◽  
Marine Realm

&lt;p&gt;Freshwater microplastics pollution has been a recent focus. River freshwater microplastics pollution are vital towards freshwater ecosystems as well as have been the prominent source-to-sink conduits to export MPs into the marine realm. Wastewater treatment plants (WWTPs) have been identified as one of the major point-sources. To date, sources-to-sinks comprehensive knowledge are highly limited. This study explored sources-to-sinks microplastics pollution i.e., WWTPs-to-river-to-marine comprehensively. The two rivers i.e., Koya River (KR) and Nishiki River (NR) which are flowing to the Seto Inland Sea (SIS) and the WWTPs effluent samples were collected from selected (n=37) stations in the Yamaguchi prefecture, Japan. Filtration, wet peroxidation, and density separation methods were employed to extract microplastics particles. Polymers were identified via attenuated total reflectance-Fourier transform infrared spectroscopy. The average microplastics abundances were found KR&amp;#8212;82.25&amp;#177;67.84 n/L and NR&amp;#8212;38.73&amp;#177;24.13 n/L for the river water, and KRWWTPs&amp;#8212;79.5&amp;#177;3.5 n/L and NRWWTPs&amp;#8212;72.25&amp;#177;23.64 n/L for WWTPs effluents, respectively. The KR were found to be more polluted than the NR. WWTPs effluents were found posing higher abundances than rivers. Significantly higher microplastics concentration were found in the WWTPs downstream stations than other river stations. Characterization revealed that small MPs (&lt;1000 &amp;#181;m) in size, fibers in shape, polymers&amp;#8212; polyethylene, polypropylene, polyethylene terephthalate, vinylon were major in both of the WWTPs effluents and rivers. WWTPs influenced river environments by means both of the abundances and microplastics characteristics (shapes-size-polymers). The estimated source-to-sink emission demonstrated a substantial number of MPs discharge into the rivers by the WWTPs (0.007&amp;#8212;0.086 billion/day) and rivers-to-SIS marine environments (1.15&amp;#8212;7.951 billion/day). The emission represented that the WWTPs were the prominent point-source to cause river microplastics pollution. Rivers were the initial sinks of the Japan land-sourced microplastics and prominent pathways to emit microplastics to the ultimate marine sink i.e., SIS. Large amounts of MPs are being generated on land sources before the plastics wastes degrade into MPs secondarily. The pollution characteristics (shapes-sizes-polymers) indicated ecotoxicological threats to these rivers and the downstream environments. Overall, this study provided an insight of sources-to-sinks pollution, fulfilled the preliminary knowledge gaps of pollution occurring land-sources, fate and loadings. We recommended microplastics pollution control at source. This study will aid in developing microplastics pollution control and management strategies for environmental protection and sustainability in the regional Japan as well as global context upon &amp;#8220;thinking globally and acting locally&amp;#8221;.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords: &lt;/strong&gt;Abundance, Point-source, Source-to-sink, Riverine microplastics pollution, Wastewater treatment plants&lt;/p&gt;

Water quality assessment in streams and wastewater treatment plants of Blantyre, Malawi

2007 ◽  
Vol 32 (15-18) ◽  
pp. 1391-1398 ◽  
Author(s):  
S.M.I. Sajidu ◽  
W.R.L. Masamba ◽  
E.M.T. Henry ◽  
S.M. Kuyeli
Keyword(s):  
Water Quality ◽  
Wastewater Treatment ◽  
Quality Assessment ◽  
Wastewater Treatment Plants ◽  
Water Quality Assessment

scholarly journals Problems and Prospects in the Political Economy of Trans-Boundary Water Issues

2000 ◽  
Author(s):  
Richard E. Just ◽  
Eithan Hochman ◽  
Sinaia Netanyahu
Keyword(s):  
Water Quality ◽  
Game Theory ◽  
Middle East ◽  
Chesapeake Bay ◽  
Case Studies ◽  
Economic Efficiency ◽  
Resource Sharing ◽  
Agricultural Sector ◽  
In Trans ◽  
Water Issues

The objective of this research was to develop and apply a conceptual framework for evaluating the potential of trans-boundary bargaining with respect to water resource sharing. The research accomplished this objective by developing a framework for trans-boundary bargaining, identifying opportunities for application, and illustrating the potential benefits that can be gained thereby. Specifically, we have accomplished the following: - Developed a framework to measure the potential for improving economic efficiency considering issues of political feasibility and sustainability that are crucial in trans-boundary cooperation. - Used both cooperative and non-cooperative game theory to assess feasible coalitions among the parties involved and to model potential bargaining procedures. - Identified empirically alternative schemes of cooperation that both improve upon the economic efficiency of present water usage and appease all of the cooperating parties. - Estimated the potential short-run and long-run affects of water reallocation on the agricultural sector and used this information to understand potential strategies taken by the countries in bargaining processes. - Performed case studies in Israeli-Jordanian relations, the relationship of Israel to the Palestinian Authority, and cooperation on the Chesapeake Bay. - Published or have in process publication of a series of refereed journal articles. - Published a book which first develops the theoretical framework, then presents research results relating to the case studies, and finally draws implications for water cooperation issues generally. Background to the Topic The increase in water scarcity and decline in water quality that has resulted from increased agricultural, industrial, and urban demands raises questions regarding profitability of the agricultural sector under its present structure. The lack of efficient management has been underscored recently by consecutive years of drought in Israel and increased needs to clean up the Chesapeake Bay. Since agriculture in the Middle East (Chesapeake Bay) is both the main water user (polluter) and the low-value user (polluter), a reallocation of water use (pollution rights) away from agriculture is likely with further industrial and urban growth. Furthermore, the trans-boundary nature of water resources in the case of the Middle East and the Chesapeake Bay contributes to increased conflicts over the use of the resources and therefore requires a political economic approach. Major Conclusions, Solutions, Achievements and Implications Using game theory tools, we critically identify obstacles to cooperation. We identify potential gains from coordination on trans-boundary water policies and projects. We identify the conditions under which partial (versus grand) coalitions dominate in solving water quality disputes among riparian countries. We identify conditions under which linking water issues to unrelated disputes achieves gains in trans-boundary negotiations. We show that gains are likely only when unrelated issues satisfy certain characteristics. We find conditions for efficient water markets under price-determined and quantity-determined markets. We find water recycling and adoption of new technologies such as desalination can be part of the solution for alleviating water shortages locally and regionally but that timing is likely to be different than anticipated. These results have been disseminated through a wide variety of publications and oral presentations as well as through interaction with policymakers in both countries.

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