The chesapeake bay story: the science behind the program

1995 ◽  
Vol 31 (8) ◽  
pp. 133-139 ◽  
Author(s):  
L. R. Shuyler ◽  
L. C. Linker ◽  
C. P. Walters
Keyword(s):  
Atmospheric Deposition ◽  
Chesapeake Bay ◽  
Point Sources ◽  
Quality Data ◽  
Control Procedure ◽  
Nutrient Loads ◽  
Nutrient Reduction ◽  
High Quality ◽  
Water Quality Data ◽  
Economic Implications

The Chesapeake Bay Program (CBP) is based on good science and high quality data. This has allowed the program to set and implement meaningful goals. The research phase resulted in the “1983 Chesapeake Bay Agreement”, which called for the jurisdictions to focus existing pollution control programs on reducing the nutrient loads to the Bay. A second “Bay Agreement” was developed and signed by the jurisdictions in 1987. This agreement contained 27 specific goals including a Basinwide Nutrient Reduction Strategy to reduce “1985 controllable” nutrient loads to the Bay by 40 percent in the year 2000. To assure high quality monitoring data, CBP established a strong quality assurance and quality control procedure which is used for all monitoring. To assist with the monitoring a computer program, “Chesapeake Bay Automated Monitoring System” was developed to evaluate the quality of field and laboratory data and to allow the data to be directly loaded into the CBP computers. The Chesapeake Bay Program Office developed models for the drainage basin and the water of the Bay. The watershed model simulates the pollutant loads from eight land uses, the majority of the point sources and atmospheric deposition. It processes these loads through the river systems and delivers the load to the Bay for use in the Bay model. The Bay model uses these loads and adds atmospheric deposition, loads from the ocean interface and loads from bottom sediments to simulate water quality data at all points in the Bay. The models were used to confirm that the 40% nutrient reduction goal was correct, resulting in an amendment to the 1987 Agreement, calling for a commitment by the jurisdictions to develop tributary specific strategies to reach the goal. The tributary strategies lay out the future goals and direction that must be taken to reach the nutrient reduction goals. These tributary strategies are being evaluated by the program office, using the models. The results of the evaluation and model simulation of the implementation progress in the basin are discussed along with the economic implications of reaching these goals.

Trends in nutrients and metals in Norwegian rivers and point sources 1990–2009

2013 ◽  
Vol 45 (3) ◽  
pp. 441-454 ◽  
Author(s):  
Eva Skarbøvik ◽  
Per Stålnacke ◽  
Øyvind Kaste ◽  
Kari Austnes
Keyword(s):  
Water Quality ◽  
Kendall Test ◽  
Point Sources ◽  
Mitigation Measures ◽  
Quality Data ◽  
Nutrient Loads ◽  
Water Quality Data ◽  
North East ◽  
The North ◽  
Zinc Cadmium

This assessment of nine river catchments in Norway covers 20 years (1990–2009) of water quality data on total phosphorus (TP), orthophosphate, total nitrogen (TN), ammonium, nitrate, copper, zinc, cadmium, lead and nickel. The nine catchments are located from the south to the north of the country and are included in the Riverine Inputs and Direct Discharges (RID) programme of the OSPAR Commission for Protection of the Marine Environment of the North-East Atlantic. The partial Mann–Kendall test was used to evaluate long-term monotonic trends. For both TP and TN, decreasing trends (p < 5%) were found in three out of nine rivers under study. Downward trends in riverine metal loads were found in 23 of 45 tests. Only one significant increasing trend in nutrient loads was found, and there were no upwards trends in metal loads. To some extent, the trends in riverine loads could be explained by trends in discharges from point sources. Even after taking potential sources of error into consideration, these results indicate that mitigation measures implemented since 1990 to reduce pressures from point sources have had an impact on water quality in Norwegian rivers.

scholarly journals Flood Flow Frequency Analysis to Estimate Potential Floodplain Nitrogen Treatment during Overbank Flow Events in Urban Stream Restoration Projects

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1568
Author(s):  
Barbara A. Doll ◽  
J. Jack Kurki-Fox ◽  
Jonathan L. Page ◽  
Natalie G. Nelson ◽  
Jeffrey P. Johnson
Keyword(s):  
North Carolina ◽  
Chesapeake Bay ◽  
Stream Restoration ◽  
Nitrogen Retention ◽  
Quality Data ◽  
Urban Stream ◽  
Water Quality Data ◽  
Total N ◽  
North Carolina Department ◽  
Overbank Flow

Stream restoration for mitigation purposes has grown rapidly since the 1980s. As the science advances, some organizations (Chesapeake Bay Program, North Carolina Department of Environmental Quality) have approved or are considering providing nutrient credits for stream restoration projects. Nutrient treatment on floodplains during overbank events is one of the least understood processes that have been considered as part of the Chesapeake Bay Program’s Stream Restoration Nutrient Crediting program. This study analyzed ten years of streamflow and water quality data from five stations in the Piedmont of North Carolina to evaluate proposed procedures for estimating nitrogen removal on the floodplain during overbank flow events. The volume of floodplain flow, the volume of floodplain flow potentially treated, and the nitrogen load retained on the floodplain were calculated for each overbank event, and a sensitivity analysis was completed. On average, 9% to 15% of the total annual streamflow volume accessed the floodplain. The percentage of the average annual volume of streamflow potentially treated ranged from 1.0% to 5.1%. Annually, this equates to 0.2% to 1.0% of the total N load retained/removed on the floodplain following restoration. The relatively low nitrogen retention/removal rates were due to a majority of floodplain flow occurring during a few large events each year that exceeded the treatment capacity of the floodplain. On an annual basis, 90% of total floodplain flow occurred during half of all overbank events and 50% of total floodplain flow occurred during two to three events each year. Findings suggest that evaluating only overbank events may lead to undervaluing stream restoration because treatment is limited by hydrologic controls that restrict floodplain retention time. Treatment is further governed by floodplain and channel size.

Simulation of organic carbon loading using MIKE 11 model: a case of River Nzoia, Kenya

2015 ◽  
Vol 10 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Edwin K. Kanda ◽  
Job R. Kosgei ◽  
Emmanuel C. Kipkorir
Keyword(s):  
Lake Victoria ◽  
Agricultural Runoff ◽  
Point Sources ◽  
Low Flow ◽  
Quality Data ◽  
Coefficient Of Determination ◽  
Lake Victoria Basin ◽  
Water Quality Data ◽  
Mike 11 ◽  
Mike 11 Model

River Nzoia is the largest river draining into the Kenyan portion of Lake Victoria. This river receives both point sources of pollution from industrial and municipal wastes, and non-point sources from agricultural runoff in the catchment. The objective of this study was to simulate dissolved oxygen (DO) and biochemical oxygen demand (BOD) of the middle section of River Nzoia using MIKE 11 model. The model was calibrated using discharge and water quality data for 2009 and validated with March–April 2013 data. The model performance was good with coefficient of determination (R2) values of between 0.845 and 0.995, Nash–Sutcliffe efficiency values of between 0.748 and 0.993 and percent bias of less than 10 for both calibration and validation of electrical conductivity (EC), DO and BOD. EC and BOD values were lower for April compared to March which could be attributed to dilution during high flows. DO values were above the recommended minimum level of 4 mg/l in all the sections of the river in the wet period but some sections had lower than 4 mg/l during low flow period. The government agencies such as Water Resources Management Authority and National Environment Management Authority should enforce the effluent standards to ensure that industries and wastewater treatment plants adhere to the maximum allowable limit for BOD and also improve their treatment efficiencies of wastewater plants so as to improve the quality of River Nzoia which is important in the overall management of the Lake Victoria basin.

Assessment of the Klang River Quality Using the Water Quality Indices

2012 ◽  
Vol 599 ◽  
pp. 237-240 ◽  
Author(s):  
Faridah Othman ◽  
Mohamed Elamin Alaa Eldin
Keyword(s):  
Water Quality ◽  
River Basin ◽  
Water Quality Index ◽  
Quality Index ◽  
River Mouth ◽  
Peninsular Malaysia ◽  
Point Sources ◽  
Quality Data ◽  
Commercial Activity ◽  
Water Quality Data

The Klang river basin is located within the state of Selangor and Kuala Lumpur, Malaysia. The Klang River drains an area of 1,288 km2 from the steep mountain rain forests of the main Central Range along Peninsular Malaysia to the river mouth in Port Klang, covering a distance of 120 km. It originates from the northern part of Selangor, drains the Klang Valley, and finally discharges itself into the Straits of Malacca. The pollution discharges for various locations along the river basin was obtained from the Water Quality and GIS group. The pollutants can come from point sources (PS) such as industrial wastewater, municipal sewers, wet market, sand mining and landfill. Pollutants can also come from non-point sources (NPS) such as agricultural or urban runoff, and commercial activity such as forestry, and construction due to rainfall event. Mathematical–computational modeling of river water quality is possible but requires an extensive validation. Besides it requires previous knowledge of hydraulics and hydrodynamics. To overcome these difficulties, a water quality index (WQI) was developed. The water quality index (WQI) is a mathematical instrument used to transform large quantities of water quality data into a single number. The purpose of this research is to classify the upstream and downstream of the Klang main river based on WQI value.

scholarly journals Challenges in Quantifying Air‐Water Carbon Dioxide Flux Using Estuarine Water Quality Data: Case Study for Chesapeake Bay

2020 ◽  
Vol 125 (7) ◽  
Author(s):  
Maria Herrmann ◽  
Raymond G. Najjar ◽  
Fei Da ◽  
Jaclyn R. Friedman ◽  
Marjorie A. M. Friedrichs ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Water Quality ◽  
Chesapeake Bay ◽  
Carbon Dioxide Flux ◽  
Quality Data ◽  
Estuarine Water ◽  
Water Quality Data ◽  
Estuarine Water Quality

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.

The Role and Control of Nutrients in Chesapeake Bay

1992 ◽  
Vol 26 (12) ◽  
pp. 2635-2644 ◽  
Author(s):  
C. F. D'Elia ◽  
L. W. Harding ◽  
M. Leffler ◽  
G. B. Mackiernan
Keyword(s):  
Chesapeake Bay ◽  
Agricultural Land ◽  
Quality Parameters ◽  
Point Sources ◽  
Nutrient Inputs ◽  
Nutrient Reduction ◽  
Multidisciplinary Study ◽  
Forest Coverage ◽  
And Control ◽  
Exact Quantification

The results of a workshop conducted by scientists who participated in a 6-year, multidisciplinary study of hypoxia on the Chesapeake Bay suggest that although an exact quantification of the management target for nutrient reduction is difficult to make, at least a 40% reduction in total inputs is needed to reduce hypoxia and restore a trophic structure that maximizes mctazoan food chains and minimizes microbial processes. Nutrient enrichment contributes to the formation of hypoxia in the Bay's main stem and lower tributaries by over-stimulating the growth of phytoplankton that ultimately decompose and consume oxygen in deep water. Enrichment effects can be traced in the sedimentary record to colonial times, but are not as easily discerned in water quality parameters from monitoring in the last 50 years. Initially, agricultural land-use practices that decreased forest coverage and increased erosion accounted for most nutrient inputs, but in this century, point and non-point sources, that result from demographic change and impact in the watershed, predominate.

scholarly journals Multiple stressors threaten the imperiled coastal foundation species eelgrass (Zostera marina) in Chesapeake Bay, USA

2017 ◽  
Author(s):  
Jonathan S Lefcheck ◽  
David J Wilcox ◽  
Rebecca R Murphy ◽  
Scott R Marion ◽  
Robert J Orth
Keyword(s):  
Water Quality ◽  
Chesapeake Bay ◽  
Zostera Marina ◽  
Multiple Stressors ◽  
Physiological Stress ◽  
Carbon Sink ◽  
Water Quality Management ◽  
Water Clarity ◽  
Quality Data ◽  
Water Quality Data

Interactions among global change stressors and their effects at large scales are often proposed, but seldom evaluated. This situation is primarily due to lack of comprehensive, sufficiently long-term, and spatially-extensive datasets. Seagrasses, which provide nursery habitat, improve water quality, and constitute a globally-important carbon sink, are among the most vulnerable habitats on the planet. Here, we unite 31-years of high-resolution aerial monitoring and water quality data to elucidate the patterns and drivers of eelgrass (Zostera marina) abundance in Chesapeake Bay, USA, one of the largest and most valuable estuaries in the world with an unparalleled history of regulatory efforts. We show that eelgrass area has declined 29% in total since 1991, with wide-ranging and severe ecological and economic consequences. We go on to identify an interaction between decreasing water clarity and warming temperatures as the primary driver of this trend. Declining clarity has gradually reduced eelgrass over the past two decades, primarily in deeper beds where light is already limiting. In shallow beds, however, reduced visibility exacerbates the physiological stress of acute warming, leading to recent instances of decline approaching 80%. While degraded water quality has long been known to influence underwater grasses worldwide, we demonstrate a clear and rapidly emerging interaction with climate change. We highlight the urgent need to integrate a broader perspective into local water quality management, in the Chesapeake Bay and in the many other coastal systems facing similar stressors.

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