(Summary)

A Literature Review of Water Quality in the Clark Fork River, with an Emphasis on the Nutrient Levels in the Middle and Lower Portions of the River

This report provides a geographic and water-quality oriented overview of the system, a chronology of political events related to the system, a review of the literature on nitrogen and phosphorus limitations and an evaluation of the published material on nutrient contributions by Champion Mill and the city of Missoula. The information in this report is based entirely on published material. However, most of the Montana Department Health and Environmental Sciences data is not directly available to the public.

(Summary)

A Multiple Lake Method to Analyze Temporal Variations

The Soap and Detergent Association initiated a lake monitoring survey from 1978 through 1983 to ascertain the effectiveness of an interim detergent phosphorus ban in the state of Wisconsin. A paired-lake approach was employed in this study. Lakes expected to be impacted by wastewater effluent nutrient loadings were monitored along with lakes not impacted by effluent. Physical, chemical and biological parameters were recorded. The ensuing statistical analysis has based comparisons between geographically proximate lake pairs, one representing an effluent impacted lake and one not. Initial work has focused upon the use of a linear model to determine whether a time-dependent change in either total phosphorus or chrorophyll-a concentration or Secchi depth could be determined between the lake pairs.

Biological parameters included algal cell concentrations enumerated by algal division. This report applies linear modeling technique to these parameters and also investigates the data requirements which would be necessary in order to increase the occurrence of determining a change associated with imposition of the detergent phosphorus ban.

(Summary)

Algal Bloom Management and Control

This report synthesizes the multitude of studies addressing the complex ecological factors contributing to the development of algal brooms in freshwater systems. The goal is to formulate a concise review of what is known about the factors causing algal blooms and to present the state of the art of bloom control and management. Emphasis is placed on blue-green algal blooms, as they are the blooms which produce the most objectionable or nuisance conditions. Algal control methods are thoroughly covered in order to provide a reference source from which possible solutions to a particular water quality problem can be selected. The review includes literature published prior to mid-1984, therefore, more recent research efforts and publications are not discussed.

(Summary)

Assessing the Water Quality Benefit of Point Source Phosphorus Control in the James River Basin

Point source phosphorus control programs have been contemplated for the James River Basin in as part of the overall effort to control eutrophication in the Chesapeake Bay. The foremost question raised by any phosphorus control program is: what response, in terms of phytoplankton biomass levels, can be expected as a result of phosphorus control programs?

The present study attempts to put this question into perspective through an analysis of the most recent water quality data and through a series of mathematical modeling simulations designed to show trends in peak phytoplankton biomass levels in the upper James River Estuary as a function of alternative loading scenarios.

(Summary)

Changes in Effluent Phosphorus Concentration Following Implementation of the Maryland Phosphate Detergent Ban

A report prepared by the Maryland Water Management Administration described results of sewage effluent monitoring before and after implementation of the state`s phosphate detergent ban in December 1985. The differences in concentration were attributed to effects of the detergent ban. The report goes on to estimate impacts on phosphorus loadings to the Chesapeake Bay from plants without phosphorus removal facilities and on chemical and sludge disposal costs for plants with phosphorus removal facilities.

The following report evaluates the statistical reliability of the reported values. A variety of data reduction and screening techniques were applied to determine sensitivity of the results to analytical assumptions. Limitations in the data resulting from the grab
sampling strategy are discussed. Apparent reductions in effluent phosphorus concentrations attributed to the ban are compared with previous projections and with results of similar studies conducted in other states.

(Summary)

Chemical Treatment and Enhanced Biological Removal of Phosphates at Wastewater Treatment Plants

The report presents a literature review and cost analysis of chemical treatment processes and enhanced biological and biological-chemical removal of phosphorus.

(Summary)

Effect of Point Source Control on Phosphorus Loads to the Chesapeake Bay

Eutrophication is considered the major concern of the Chesapeake Bay due to nutrient enrichment from both point and nonpoint sources in the basin. Several point source control alternatives are being contemplated for the Bay. In order to evaluate the water quality impact (i.e., reduction of eutrophication) the reduction of phosphorus loads to the Bay associated with each control alternative needed to be determined. That is, the reduced phosphorus loads discharged from the publicly owned treatment works (POTWs) needed to be quantified, as well as the reduced loads to the Bay. Further this issue is put into a better perspective by comparing the reduced point source loads under various control alternatives with the nonpoint source loads from the Bay drainage area.

The results of such an analysis can then be used to assess the water quality improvement, if any, resulting from these control measures. Such water quality impact analysis will, in most cases, require a water quality model to predict the impact. A separate study was conducted to assess the water quality impact in the James River Estuary in Virginia under various control alternatives. Thus, the results from this study of reduced loads provided input to the ongoing James River Estuary modeling study.

(Summary)

Environmental factors and their consideration in the management of submersed aquatic vegetation: A review

A variety of environmental factors interact in affecting the productivity, distribution, and species composition of submersed macrophyte communities. Foremost among these are light, water temperature, sediment composition, and and inorganic carbon availability. Light and temperature are important in determining morphology and distribution (with latitude, season and depth), thereby influencing productivity and species composition as well. Sediments provide an important source of nutrients, principally N, P, and micronutrients, which are relatively less available in the surface waters on most aquatic systems. Sediment composition (i.e., texture and organic matter content) markedly affects macrophyte growth rates, due to its influence on nutrition, but possibly due also to the inhibitory effects of reduced chemical constituents formed under anaerobic conditions. Due to slow CO₂ diffusion rates in water and to boundary layer resistance to carbon uptake at leaf surfaces, the availability of inorganic carbon can be an exceptionally important factor limiting the productivity of submersed macrophytes in freshwater systems. Prior to the implementation of management procedures designed to modify aquatic macrophyte production or community composition, it is necessary to consider both aquatic system use and the localized role of these important growth regulating factors.

(Summary)

Environmental intervention analysis: Wisconsin`s ban on phosphate detergents

Intervention analysis was used to estimate the decrease in total phosphorus load on the two large wastewater treatment plants in Milwaukee, WI, caused by the ban on phosphate laundry detergents that went into force on July 1, 1979.

(Summary)

Eutrophication in Chesapeake Bay Before and After Implementation of Maryland`s Phosphate Detergent Ban

A statewide phosphate detergent ban went into effect ln Maryland on December 1, 1985. Similar legislation became effective in the District of Columbia in September of 1986. Projected benefits included improvements in the quality of Chesapeake Bay waters due to reductions in phosphorus loadings from municipal discharges without phosphorus removal facilities. Limited data indicate that phosphorus concentrations in sewage discharged from the Maryland treatment plants without phosphorus removal facilities decreased an average of 33%. However, direct relationships between phosphorus loading and biological responses in the Bay, as measured by peak algal densities or by the depletion of dissolved oxygen from bottom waters, cannot be presumed because these responses are controlled by many factors including phosphorus, nitrogen, light temperature, and hydrodynamic features. This report describes eutrophication related water quality conditions in the Bay, its estuaries, and its tributaries before and after implementation of the phosphate detergent bans, based upon analysis of monitoring data collected between mid 1984 and mid 1987.

Analyses of river monitoring data indicate that reductions in phosphorus loadings to the Bay resulting from the phosphate detergent ban are similar to projections made prior to the ban`s implementation. Other factors, including municipal phosphorus removal, reduced phosphorus loads further during the study period. However, corresponding decreases in algal productivity were not detected at Bay or estuary stations. While this result could reflect algal changes that were too small to detect, the lack of algal response is clearly consistent with observations made in this report and by others that factors other than phosphorus, particularly nitrogen, regulate algal growth and related water quality conditions.

The full range of costs and benefits must be considered in evaluating the phosphate detergent ban and in comparing it with alternative strategies for achieving the same management objectives. Considering the small changes in phosphorus loading resulting from the ban and the importance of limiting nutrients other than phosphorus, it is clear that the ban in itself contributes 1ittle to the cause of restoring the Bay.

(Summary)

Eutrophication Modeling of James Estuary, Virginia

A modeling study was conducted to trace the fate and transport of nutrients (nitrogen and phosphorus) in the lower James River Estuary. The study consisted of the following key technical tasks:

• Review of the results from an earlier modeling study of the upper estuary


• Expansion of the upper estuary model estuary to include the lower estuary


• Analysis of available data in the lower estuary


• Calibration of the expanded model


• Model projections to quantify the fate and transport of nutrients

(Abstract)

Inputs of Phosphorus to Aquatic Systems from Machine Dishwashing Detergents: An Analysis of Measured and Potential Loading

Four lines of investigation appear to converge on the same conclusion: Phosphorus inputs to lakes and streams in Massachusetts and Vermont from machine dishwashing detergent comprise a very small portion of the total load to those systems. Analysis of stream data from two intensive studies in Massachusetts, a phosphorus loading analysis for Lake Champlain in Vermont, assessment of the itemized loads to multiple New England lakes, and extrapolation of wastewater treatment facility responses to the reduction of phosphorus in laundry detergents all indicate that there are very limited contributions of phosphorus from dishwashing detergent sources and minimal potential to realize any significant reduction in loading from a ban on P in machine dishwashing detergent.

Overall, reductions in phosphorus achievable through restrictions in the amount of P in machine dishwashing detergents will not meaningfully reduce P concentrations and associated algal levels in Massachusetts or Vermont waters. The greatest reduction in P loading through restriction of P content of machine dishwashing detergent is associated with aquatic systems that are strongly influenced by WWTF discharges subjected to no active P removal. Such systems are rare in New England, and even with such restrictions these heavily impacted waters will fall far short of achieving water quality goals.

The range of P contribution from machine detergent for the cases analyzed in this report was 0.2 to 10% of total P load, with an estimated possible maximum of 17% for systems dominated by WWTFs practicing only primary treatment with no addition of chemicals for P removal. The potential for reducing the P load through restriction of P content of machine dishwashing detergent is limited to 0 to 7% in the cases studied, with estimates >2% associated with high loading from WWTFs applying no active P removal. Again, such systems are rare in New England and would not be detectably improved by reductions in machine dishwashing detergent P content. Load reductions of <2% that might be achieved by a machine dishwashing detergent P ban in areas served by septic systems or WWTFs with active P removal would also not result in any significant reduction in P load or concentration in the associated aquatic system.

(Summary)

Modeling blue-green algal blooms in the lower Neuse River

A mathematical model of the lower Neuse River was developed to help evaluate control alternatives for blue-green algal blooms.

(Summary)

Modeling Blue-Green Algal Blooms in the Lower Neuse River, NC

Segments of the lower Neuse River between Goldsboro and New Bern, North Carolina, during the 1980`s, revealed alarming symptoms of advanced eutrophication, culminating in the appearance and persistence of nuisance blue-green algal blooms. Specific symptoms of eutrophication in the lower Neuse are generally high rates of primary productivity and standing stocks of a1ga1 biomass; periodic spring and summer blooms of nuisance blue-green algae; and both nitrogen (ammonia and nitrate) and phosphorus (orthophosphate) concentrations exceeding levels which are considered to be growth-limiting to nuisance species.

To help address these questions, a mathematical model of the lower Neuse River was developed. The modeling effort focuses on the understanding of the mechanisms initiating and sustaining algal blooms in the lower Neuse River. Water quality data collected by the Institute of Marine Sciences, University of North Carolina in 1983 and 1984 were used for model development. This paper presents the model development and results of model calibration analyses.

(Summary)

Modeling the Blue-Green Algal Bloom in the Neuse River Estuary

An estuarine eutrophication model was developed to quantify the blue-green a1gal blooms in the lower Neuse River, North Carolina. The important features of the model include four functional groups of phytoplankton: diatoms, greens, non-nitrogen fixing blue-greens, and nitrogen fixing blue-greens; a two-layer mass transport pattern in a portion of the estuary; and the effect of salinity on algal growth. In addition, each of the two layers in the water column is divided into longitudinal segments to account for the concentration gradients of the water quality constituents.

(Summary)

Nutrient loads to Wisconsin lakes: Part I. Nitrogen and phosphorus export coefficients

Export coefficients for phosphorus and nitrogen were derived for 17 watersheds in Wisconsin.

(Summary)

Nutrient loads to Wisconsin lakes: Part II. Relative importance of nutrient sources

A comparison of municipal wastewater treatment plant and nonpoint source nutrient loads to Wisconsin`s 14,927 inland lakes was performed.

(Summary)

Phosphorus and Nitrogen Removal from Municipal Wastewater: Principles and Practice (Second Edition)

This document summarizes the available technologies for removing phosphorus and nitrogen from municipal sewage, with emphasis on those that are expected to see prominent use either because of their treatment capabilities or their ease and cost of operation, or both. The information is presented in two sequential blocks: one on the chemical, biological, and physical principles behind the available treatment technologies; a second on the design and operation of processes and systems based on these principles.

(Summary)

Phosphorus Loads Discharged from the POTWs in the Chesapeake Bay Drainage Basin

This study is designed to address the issue phosphorus loads into the Chesapeake Bay and to put the point source phosphorus loads into perspective by revising the 1980 loads as well as by updating the loads to the 1983 conditions. In order to estimate the phosphorus loads from many publicly owned treatment works (POTWs) where effluent phosphorus concentrations are not measured, default values are developed based on measured and reported phosphorus concentrations at a number of plants in the region.

(Summary)

Phosphorus Loads to the Chesapeake Bay System

The phosphorus loads from the publicly owned treatment works (POTWs) or municipal wastewater treatment plants in the Chesapeake Bay basin can be estimated based on existing data and information. However, not all these phosphorus loads will reach the tidal system of the Bay and the Bay proper after they are released from the POTWs. A portion of the municipal phosphorus loads in the upper sub-basins of major tributaries will be lost before it reaches the fall line. That is, one pound of phosphorus which enters the free-flowing river is subject to in-stream processes (e.g., settling, algal uptake, mineralization, dilution, etc.) which result in a reduced load arriving at the fall line than originally entered the river.

The purpose of this study is to quantify the POTW phosphorus loads entering the Bay. Three major river basins (Susquehanna, Potomac and James) were selected for the study.

(Summary)

Practical Tools for Estuarine Nutrient Control

In this paper, the estuarine modering studies are presented to demonstrate the use of models to guide nutrient controls. The first study uses a one-dimensional tidally averaged steady state model for the upper James River Estuary in Virginia. In that study, phytoplankton growth and nutrient dynamics are approximated as a seasonal event, an approximation particularly valid under summer low and steady flow conditions. The mode1 was used to evaluate point source phosphorus control alternatives in the James River Basin and assess the water quality impacts by comparing the reduction of summer peak chlorophyll a levels in the estuary.

The second modeling study is development of a model for blue-green algal blooms in the lower Neuse River in North Carollna. The study area is a tidal and estuarine portion of the river with repeated blue-green algal blooms during the past decade. Spring/summer/fall blooms at times coat the river with green paint-like blooms. The water quality model developed includes four different algal groups (diatoms, greens, non-nitrogen fixing and nitrogen fixing blue-greens). In addition to nutrients and dissolved oxygen, seasonal variations of phytoplankton nutrient dynamics are simulated on a tidally averaged time-variable basis. The model is able to mimic the observed phytoplankton growth in 1983, 1984, and l985 with different hydrologic conditions. Based on the modeling results, a hypothesis for the initiation and maintenance of blue-green blooms has been developed.

(Summary)

Statistical Assessment of a Limnological Data Set

In a study of Wisconsin Lakes, to examine the effects upon water quality of imposition of a ban on detergent phosphorus, the design protocol employed the concept of test lakes and reference lakes. A pairing was made of each test lake with a reference lake having as many similar characteristics as possible with the test lake except for a loading of phosphorus from municipal wastewater effluent or septic tank seepage. The responses measured for each lake were physical, chemical and biological in nature. Measurements were taken both before and after imposition of the ban. To estimate the potential effect of the ban, three forms of statistical models were used; (i) for each test lake a model using the reference lake variable as a covariate and the ban as a classification variable, (ii) a comprehensive model for all of the lakes combined using the reference lakes as covariates and the test lakes as dummy variables, and (iii) multivariate models providing multiple comparison estimates for pre- and post-ban differences. The advantage to the paired lake approach is the potential for variance reduction, and an examination of this was made for several data sets. In this paper are discussed the comparisons of the modeling procedures as well as estimates of the “ban effects.” Also presented are some of the observed distributional characteristics of the measured responses.

(Summary)

Status of Water Quality and Point and Non-point Source Pollution in the Southeastern United States

A review of the water quality in estuaries, public lakes, and streams in nine Southeastern states was undertaken, with somewhat more emphasis placed on lakes than estuaries and streams. The states studied were: Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee, and Virginia. In general, the presentations for estuaries and streams were restricted to a review of information presented in each state`s 1984 Section 305(b) report and and its submission to the Association of Interstate Water Pollution Control Administrators` “State`s Evaluation of Progress” (STEP) program. In addition to these data, municipal wastewater treatment plant (WWTP) total phosphorus load estimates were calculated for lakes. The results of this project are summarized.

(Summary)

The Impact of Banning Phosphate Containing Detergents on the Water Quality of Inland Wisconsin Lakes

The impact of a three-year Wisconsin detergent phosphate ban on Wisconsin lake water quality was evaluated through research on Wisconsin lakes likely to be affected by changes in phosphate discharges. The ban was imposed on July 1, 1979 and ended June 30, 1982.

(Summary)

The impact of detergent phosphorus bans on receiving water quality

This paper presents results of several field and laboratory investigations designed to position the impact of detergent phosphorus contributions to surface water quality.

(Abstract)

The relationship between wastewater treatment plants and nutrient impaired surface water bodies in seven northern states

Discharges from wastewater treatment plants (WWTPs) contribute significantly to nutrient loading of surface water bodies and to water body impairments in specific systems. As a result attention has been focused on the control of discharges from these point sources. However, the relationship between nutrient impairment and WWTP discharge on a broader scale is unclear. To investigate this relationship we examined the following factors in seven northern states: 1) the percentage of nutrient impaired water bodies that receive discharges from WWTPs directly or
via tributaries 2) the percentage of WWTPs with advanced treatment to remove phosphorus (P) 3) the proportion of Total Maximum Daily Loads (TMDLs) for nutrients identifying WWTPs as significant sources of phosphorus and the fraction of the phosphorus load attributable to WWTPs. The results of this study suggest that on a state and regional scale WWTPs represent a small fraction of the P loading to impaired water bodies. However, in specific systems they may be the most important P source.

(Summary)

The Role of Estuarine Modeling in Nutrient Control

Two case studies are presented to demonstrate how estuarine water quality models can be used in planning eutrophication control. In the first study, a steady-state model is used to assess the impact of point source phosphorus reduction on the phytoplankton biomass in the upper James Estuary in Virginia during the summer months. The modeling results indicate that phosphorus is in ample supply to support the phytoplankton growth in the system. However, substantial reduction of loads by phosphorus removal at the wastewater treatment plants would lead to a phosphorus limiting condition thereby lowering the phytoplankton biomass levels. In the second study, a time-variable model is developed to investigate the potential of blue-green algal (Microcystis) blooms in the Neuse Estuary in North Carolína. More specifically, the model is designed to address two management questions. First, recognizing that high non-point nitrogen loads in the spring months would lead to a proliferation of non-nitrogen fixing blue-green genera, should parallel control of nitrogen be considered? Second, in light of the potential for algae species dominance to shift, is control of nitrogen fixing blue-green algal blooms possible? Based on the modeling calibration results using data from 1983, 1984 and 1985 under different hydrologic conditions, freshwater flow to the estuary is found to be a key factor in controlling blue-green algal blooms in the Neuse Estuary.