Chesapeake Bay’s “forgotten” Anacostia River: eutrophication and nutrient reduction measures

Abstract A feasibility analysis of tertiary treatment for Organic Liquid Agricultural Waste is presented using filamentous algae belonging to the genus Cladophora sp. as an alternative to chemical tertiary treatment. The main advantages of tertiary treatments that use biological systems are the low cost investment and the minimal dependence on environmental variables. In this work we demonstrate that filamentous algae reduces the nutrient load of nitrate (circa 75%) and phosphate (circa 86%) from the organic waste effluents coming from dairy farms after nine days of culture, with the added advantage being that after the treatment period, algae removal can be achieved by simple procedures. Currently, the organic wastewater is discarded into fields and local streams. However, the algae can acquire value as a by-product since it has various uses as compost, cellulose, and biogas. A disadvantage of this system is that clean water must be used to achieve enough water transparency to allow algae growth. Even so, the nutrient reduction system of the organic effluents proposed is friendly to the ecosystem, compared to tertiary treatments that use chemicals to precipitate and collect nutrients such as nitrates and phosphates.

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Summary of water- and sediment-quality data for Anacostia River well sites sampled in July-August 2002

Open-File Report ◽

10.3133/ofr200373 ◽

2003 ◽

Author(s):

Cherie V. Miller ◽

Cheryl A. Klohe

Keyword(s):

Sediment Quality ◽

Quality Data ◽

Anacostia River ◽

Water And Sediment ◽

Water And Sediment Quality

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Fate and Transportation of PAH and Metal Comtaminants in the Anacostia River Tidal Region

10.21236/ada360167 ◽

1999 ◽

Author(s):

R. B. Coffin ◽

J. W. Pohlman ◽

C. S. Mitchell

Keyword(s):

Anacostia River

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A Collaborative Approach to Upgrading to Limits of Technology at the York River Treatment Plant

Water Practice & Technology ◽

10.2166/wpt.2009.057 ◽

2009 ◽

Vol 4 (3) ◽

Author(s):

I. Venner ◽

J. Husband ◽

J. Noonan ◽

A. Nelson ◽

D. Waltrip

Keyword(s):

Chesapeake Bay ◽

Phase 1 ◽

Treatment Plant ◽

Cost Effective ◽

Design Flow ◽

Nutrient Reduction ◽

York River ◽

Hampton Roads ◽

Key Issues ◽

Virginia Department

In response to rapid population growth as well as to address the nutrient reduction goals for the Chesapeake Bay established by the Virginia Department of Environmental Quality (VDEQ), the Hampton Roads Sanitation District (HRSD) initiated the York River Treatment Plant (YRTP) Expansion Phase 1 project. The existing YRTP is a conventional step-feed activated sludge plant and is rated for an average daily design flow of 57 million liters per day (MLD). This project proposes to expand the existing treatment capacity to 114 MLD and to reduce the nutrients discharged to the York River, a tributary for the Chesapeake Bay. In order to meet the effluent limits set by the VDEQ, a treatment upgrade to limit of technology (LOT) or enhanced nutrient removal (ENR) was required. Malcolm Pirnie worked with HRSD and the VDEQ to develop and evaluate ENR process alternatives to achieve the required effluent limits with the goal of determining the most reliable and cost effective alternative to achieve the aggressive nutrient reduction goals. This paper will highlight the key issues in determining the most desirable treatment process considering both economic and non-economic factors.

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Bacterioplankton, Phytoplankton, and Zooplankton Communities in a British Columbia Coastal Lake Before and After Nutrient Reduction

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f86-188 ◽

1986 ◽

Vol 43 (8) ◽

pp. 1504-1514 ◽

Cited By ~ 20

Author(s):

F. Joan Hardy ◽

Ken S. Shortreed ◽

John G. Stockner

Keyword(s):

British Columbia ◽

Sockeye Salmon ◽

Inorganic Nitrogen ◽

Size Fraction ◽

Growing Season ◽

Nutrient Reduction ◽

Nitrogen And Phosphorus ◽

Coastal Lake ◽

Before And After ◽

High Concentrations

Inorganic nitrogen and phosphorus were applied weekly during the growing season from 1980 to 1982 and twice weekly in 1983 to Hobiton Lake, a warm monomictic coastal lake in British Columbia. The lake was not fertilized in 1984. Average numbers of bacteria during the growing season decreased from a high of 1.53 × 106∙mL−1 in the fertilized condition to 0.84 × 106∙mL−1 in the unfertilized condition. Chlorophyll a concentrations decreased from a maximum seasonal average of 2.69 μg∙L−1 (1981) to 1.30 μg∙L−1 (1984), and algal numbers decreased from 5.83 × 104∙mL−1 (1983) to 2.29 × 104∙mL−1 (1984). Although the numbers of phytoplankton in each size fraction (picoplankton, nanoplankton, or microplankton) decreased in the unfertilized condition, the greatest change was an almost fourfold decrease in picoplankton, which consisted of 90% cyanobacteria (primarily Synechococcus spp.). Abundance of the large diatoms Rhizosolenia spp. and Melosira spp. increased in 1984, resulting in an increase in average seasonal algal volume. Average densities of medium (0.15–0.84 mm) and large (0.85–1.5 mm) zooplankton were greatest in 1982, while rotifers and small zooplankton (0.10–0.14 mm) were most dense in 1984 following nutrient reduction. The lake had relatively high concentrations of planktivorous juvenile sockeye salmon (Oncorhynchus nerka) that appeared to minimize any direct effect of nutrient additions on zooplankton densities.

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