Diurnal fluctuation of indicator microorganisms and intestinal viruses in combined sewer system

2009 ◽  
Vol 60 (11) ◽  
pp. 2791-2801 ◽  
Author(s):  
W. J. Kim ◽  
S. Managaki ◽  
H. Furumai ◽  
F. Nakajima
Keyword(s):  
Indicator Bacteria ◽  
Fecal Coliforms ◽  
Effective Control ◽  
Diurnal Fluctuation ◽  
Sewer System ◽  
Indicator Microorganisms ◽  
E Coli ◽  
Variation Patterns ◽  
Combined Sewer ◽  
Combined Sewer System

Combined sewer overflow (CSO) has been considered to be a source of pathogenic microorganisms for aquatic environment. For the effective control and treatment of CSOs, the microbial behavior in combined sewer system (CSS) needs to be investigated. In this study, whole-day extensive monitoring of indicator microorganisms and intestinal viruses in dry weather flow (DWF) was conducted at a small residential urban drainage area with CSS. All indicator bacteria represented similar diurnal variations in the two different monitoring campaigns; their concentrations gradually decreased to the minimum at the dawn (around 5 a.m.), increased sharply to the maximum around 7 to 8 a.m., and remained rather constant from noon to midnight. On the other hand, neither coliphages nor intestinal viruses showed any concentration peaks in the morning. The maximum/minimum load ratios ranged from 18 to 42 for total coliforms, fecal coliforms and E. coli, whereas those ratios for coliphages, enteroviruses and noroviruses G2 showed greater values than those for indicator bacteria. These results indicate that the diurnal variation patterns of bacterial and viral concentrations in DWF should be considered, which affect the discharge characteristics of each microorganism and the loads of bacteria and viruses in CSOs significantly vary with the overflow time as well.

Water Quality of Swimming Pools in Jerusalem

1993 ◽  
Vol 27 (7-8) ◽  
pp. 287-294 ◽  
Author(s):  
S. Lerman ◽  
O. Lev ◽  
A. Adin ◽  
E. Katzenelson
Keyword(s):  
Water Quality ◽  
Fecal Coliforms ◽  
Pathogenic Microorganisms ◽  
Swimming Pools ◽  
Indicator Organisms ◽  
Indicator Microorganisms ◽  
E Coli ◽  
Safe Water ◽  
Indirect Information

The Israel Ministry of Health is now revising its regulations for the assurance of safe water quality in public swimming pools. Since it is not possible to monitor each of the pathogenic microorganisms, it is often recommended to monitor indicator bacteria which provide indirect information on the water quality in the swimming pool. Three indicator microorganisms are often recommended: coliform counts (total coliforms, fecal coliforms or E. Coli), staphylococcus aureus and pseudomonas aeruginosa. A four year survey of the water quality of swimming pools in the Jerusalem District was conducted in order to determine whether the monitoring of all three indicators is necessary to assure safe water quality or is it sufficient to monitor only a single microorganism. A statistical analysis, conducted by using several different statistical techniques, reveals that the populations of the three indicator organisms are significantly interdependent but the correlations between each pair of these indicators are not sufficient to base a prediction of any of the organisms based on the measurements of the others. Therefore, it is concluded that monitoring of all three indicators should be recommended in order to provide an adequate picture of the water quality in swimming pools.

Reducing Pollutant Loads from Philadelphia's Combined Sewer System with Green Stormwater Infrastructure

2012 ◽  
Vol 2012 (5) ◽  
pp. 952-965 ◽  
Author(s):  
Matthew J. Vanaskie ◽  
Jim Smullen ◽  
Rajesh Rajan ◽  
Mark Maimone ◽  
Marc Cammarata
Keyword(s):  
Sewer System ◽  
Pollutant Loads ◽  
Combined Sewer ◽  
Combined Sewer System ◽  
Green Stormwater Infrastructure

Cesium and strontium loads into a combined sewer system from rainwater runoff

2016 ◽  
Vol 183 ◽  
pp. 1041-1049 ◽  
Author(s):  
Nao Kamei-Ishikawa ◽  
Daiki Yoshida ◽  
Ayumi Ito ◽  
Teruyuki Umita
Keyword(s):  
Sewer System ◽  
Combined Sewer ◽  
Combined Sewer System ◽  
Rainwater Runoff

scholarly journals Analysis of the residual nutrient load from a combined sewer system in a watershed of a deep Italian lake

2019 ◽  
Vol 571 ◽  
pp. 202-213 ◽  
Author(s):  
Laura Barone ◽  
Marco Pilotti ◽  
Giulia Valerio ◽  
Matteo Balistrocchi ◽  
Luca Milanesi ◽  
...  
Keyword(s):  
Nutrient Load ◽  
Sewer System ◽  
Combined Sewer ◽  
Combined Sewer System

scholarly journals Air flow model development and application in a complex combined sewer system

2020 ◽  
Vol 82 (8) ◽  
pp. 1687-1700 ◽  
Author(s):  
Hasan Zobeyer ◽  
David Z. Zhu ◽  
Stephen Edwini-Bonsu
Keyword(s):  
Flow Rate ◽  
Flow Model ◽  
Air Flow ◽  
Model Development ◽  
Iterative Solution ◽  
Momentum Equation ◽  
Air Flow Rate ◽  
Sewer System ◽  
Combined Sewer ◽  
Combined Sewer System

Abstract A steady-state air flow model was developed and applied in a complex combined sewer system in the city of Edmonton, Alberta, Canada. The model solves the continuity at each junction and the momentum equation for the links coupled with dropshaft and other manholes. The dropshaft pressure gradient is computed using the dropshaft equation and air flow rate through manhole pickholes is computed considering the opening as an orifice. A leakage factor is used as a calibration parameter to represent the area through which air can leak from the manholes into the neighborhood. The model uses an iterative solution algorithm with a forward sweep for the continuity and backward sweep for the momentum equation. An underrelaxation is applied to update pressure in each iteration for model stability. The model was calibrated and validated by using the measured air flow rate and manhole pressure in the sewer network, with good results. An analysis of the air flow characteristics shows that a significant amount of air is brought into the system due to a large headspace in the upstream trunk but over 70% of this air is released into the neighborhood due to reduced headspace in the downstream trunk.

Settleable Solids in a Combined Sewer System, Settling Characteristics, Heavy Metals, Efficiency of Storm Water Tanks

1993 ◽  
Vol 27 (5-6) ◽  
pp. 153-164 ◽  
Author(s):  
S. Michelbach ◽  
C. Wöhrle
Keyword(s):  
Heavy Metals ◽  
Settling Velocity ◽  
Urban Runoff ◽  
Stormwater Treatment ◽  
Sewer System ◽  
Sewer Systems ◽  
Combined Sewer ◽  
Combined Sewer System ◽  
Water Tanks ◽  
The Relationship

Sedimentation and transportation of mineral and organic pollutions in combined sewer systems are not completely understood. For better understanding, samples of sediment, slime and urban runoff were taken from the combined sewer system of Bad Mergentheim. The settling velocity of settleable solids was measured with a settling apparatus. Typical settling curves for sediment, slime and wastewater were put together. Some of the samples were analysed for heavy metals and organic micro-pollution. By this the relationship between settling velocity and the load of heavy metals can be shown. The gained data are of interest for the design of clarifier tanks for stormwater treatment.

Evaluating spatial-temporal variations and correlation between fecal indicator bacteria (FIB) in marine bathing beaches

2015 ◽  
Vol 13 (4) ◽  
pp. 1029-1038 ◽  
Author(s):  
Jingfeng Fan ◽  
Hongxia Ming ◽  
Lili Li ◽  
Jie Su
Keyword(s):  
Temporal Variations ◽  
Horizontal Distribution ◽  
Indicator Bacteria ◽  
Fecal Coliforms ◽  
Fecal Indicator ◽  
Bacterial Indicators ◽  
E Coli ◽  
Before And After ◽  
Rain Events ◽  
Different Levels

The horizontal distribution and temporal variation of bacterial indicators (total coliforms (TC), fecal coliforms (FC), enterococcus (EC) and Escherichia coli (E. coli)) were investigated to identify the proper bacterial indicators for a marine bathing beach in China. Two different sampling efforts were conducted during dry weather and two large rain events at Xinghai Bathing Beach in Dalian, China. Samples were collected from three different water depths and analyzed for the four indicator bacteria. The results indicated that all four bacterial indicators exceeded the single sample standards at different levels. Specifically, the water quality exceeded the standard for TC, FC, EC and E. coli in 7%, 28%, 38% and 10% of the samples, respectively. Comparison of the rate of the indicators before and after rainfall revealed a significant increasing post-rainfall. The concentrations of bacteria differed significantly with distance from the shoreline, with knee-depth near the shore exceeding the standard most frequently. This was primarily due to contamination by excessive sewage discharge and rainfall. Based upon the concentration of indicators and exceedance rates, as well as the correlation between indicators, both EC and FC should be evaluated at the same time as fecal pollution bacterial indicators in marine bathing beaches in China.

Sign in / Sign up

Export Citation Format

Share Document