An Assessment of Water Quality Impacts of Maintenance Dredging on the Upper Mississippi River in 1979

An Assessment of Water Quality Impacts of Maintenance Dredging on the Upper Mississippi River in 1979 PDF

Author: Dennis D. Anderson

Publisher:

Published: 1981

Total Pages: 112

ISBN-13:

DOWNLOAD EBOOK →

In connection with the 1979 maintenance dredging season, the Corps of Engineers, St. Paul District, investigated the water quality impacts of hydraulic and clamshell dredging operations at five selected sites on the Upper Mississippi River. Turbidity values and suspended solids were monitored at all sites, and selected chemical parameters were monitored at two hydraulic dredging sites. At most sites, dredging and disposal operations produced minor and localized changes in water quality. No statistically significant increases in chemical parameters were noted due to hydraulic dredging operations. However, effluents from the disposal area did cause some elevations of heavy metals (cadmium, lead, nickel, zinc, copper, chromium) and total ammonia. None of the chemical parameters tested exceeded their maximum permissible level proposed by Federal Water Quality Criteria. The five monitoring studies generally indicated that rapid settling and dilution occurred near and downstream of dredging and disposal operations.

An Assessment of Water Quality Impacts of Maintenance Dredging on the Upper Mississippi River in 1978

An Assessment of Water Quality Impacts of Maintenance Dredging on the Upper Mississippi River in 1978 PDF

Author: Dennis D. Anderson

Publisher:

Published: 1981

Total Pages: 125

ISBN-13:

DOWNLOAD EBOOK →

In 1978, the St. Paul District, Corps of Engineers, monitored five dredging operations at various locations on the Upper Mississippi River, including three hydraulic dredging operations and two mechanical (clamshell) dredging operations. All five studies were conducted in areas with relatively coarse sediments. Overall, with the methods used for disposal of the dredged material at the five sites studied, no major degradation of water quality was evidenced for either the mechanical (clamshell) or hydraulic dredging and disposal operations. Bottom sediment samples from many historical dredging sites were analyzed for bulk chemistry, particle size distribution, and settleability. Frequency of dredging at a site did not appear to be a major factor in determining the degree of contamination. High levels of contaminants were closely associated with the finer sediments. Sites in and immediately downstream of the Twin Cities metropolitan area contained the most contaminated sediments.

Environmental Impact of Dredged Material Disposal on the Upper Mississippi River at Crosby Slough

Environmental Impact of Dredged Material Disposal on the Upper Mississippi River at Crosby Slough PDF

Author:

Publisher:

Published: 1978

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK →

This study was designed to investigate the environmental effects of disposal of material from maintenance dredging on the aquatic habitat around Island 117, Pool 8, Upper Mississippi River. Dredging impacts of disposal of dredged material in the past have included the conversion of productive aquatic and semiaquatic habitat to sandy shoals and islands, as well as the impairment of backwater circulation. Disposal activity at Island 117 during 1974 produced no measurable effect on those variables considered. The reasons for the negligible impact may have been as follows: (1) a relatively small amount of material was deposited at the site in 1974 (11,144 cu yds compared to a 19-year average job size of 65,500 cu yds); (2) dredged material was not allowed to pass over the crest of Island 117 into backwater areas as it had in past years because of court-ordered dredged material placement limitations imposed by the State of Wisconsin; and (3) the variance of the baseline data, caused by annual, seasonal, and diel fluctuations, was significant for most variables. If 1974 disposal activities affected water quality in the study area, these effects were masked by the natural background variation in the variables considered. Turbidity and nitrite-nitrogen, which were increased by disposal of dredged material in 1973, were not significantly altered during 1974.

Municipal Wastewater Treatment

Municipal Wastewater Treatment PDF

Author: Andrew Stoddard

Publisher: John Wiley & Sons

Published: 2003-03-20

Total Pages: 672

ISBN-13: 0471463523

DOWNLOAD EBOOK →

A thorough analysis of public policy and the Clean Water Act'seffect on water quality in the U.S. Using water quality data and historical records from the past 60years, this book presents the measured impact of the 1972 CleanWater Act on domestic waterways-ecologically, politically, andeconomically. Municipal Wastewater Treatment supports thehypothesis that the Act's regulation of wastewater treatmentprocesses at publicly owned treatment works (POTW) and industrialfacilities has achieved significant success. The authors' case ispresented in: * Background information on the history of water pollution controland water quality management * Chapters addressing long-term trends in biochemical oxygen demandloadings from municipal wastewater plants and the "worst-case"dissolved oxygen levels in waterways downstream of point sourcesbefore and after the Clean Water Act * Nine case study assessments of long-term trends of pollutantloading water quality and environmental resources associated withPOTW discharges Using long-term trends in dissolved oxygen as the key indicator ofwater quality improvements, this book provides a detailedretrospective analysis of the effectiveness of the water pollutioncontrol policies and regulations of the 1972 Clean Water Act. Thesuccesses of the Act that have been achieved over the past 30 yearsare placed in the historical context of the "Great SanitaryAwakening" of the 19th century and changes in public policies forwater supply and water pollution control that have evolved duringthe 20th century to protect public health and the intrinsic valueof aquatic resources. Case study sites include the ConnecticutRiver, Hudson-Raritan Estuary, Delaware Estuary, Potomac Estuary,Upper Chattahoochee River, Ohio River, Upper Mississippi River, andWillamette River. Complete with end-of-chapter summaries and conclusions, MunicipalWastewater Treatment: Evaluating Improvements in National WaterQuality is an essential book for engineers, scientists, regulators,and consultants involved in water quality management and wastewatertreatment, as well as students of environmental engineering,environmental science, and public policy.

Lanterna Rally - Theme by Grace Themes