REGULATING LOADS TO RECEIVING WATERS: CONTROL PRACTICES FOR COMBINED SEWER OVERFLOWS IN JAPAN

Author(s):  
Eiichi Nakamura
2013 ◽  
Vol 8 (3-4) ◽  
pp. 409-416
Author(s):  
J. Pollert

In 2005 one of major Czech manufacturers of glass reinforced plastic pipes asked the Department of Sanitary and Ecological Engineering to develop a new type of combined sewer overflows (CSO) chamber that could become a part of their manufacturing programme. The main requirements were economy of production, easy and fast installation on the field and increased protection of receiving waters. A simple object consisting of a pipe placed above another one was designed. The object begins with a stilling chamber formed by a conical expansion of the inlet pipe. It is separated from the overflow object itself by a downflow baffle designed to trap floating objects. The CSO chamber is equipped by a flow regulation device (e.g. vortex valve or throttle pipe) at the end. Excess water flows through a slit in the top of the bottom pipe into the upper pipe and from there to the receiving water. More than 15 prototypes were already installed in the Czech and Slovak Republics and more than 20 are planned to be built in Europe. We hope this type of CSO CHAMBER will help to decrease the cost of construction of new sewers and reconstruction of old ones. Its higher efficiency of separation of suspended particles might also contribute to the improvement of the quality of receiving water bodies according to Water Framework Directive 2000/60/EC.


1996 ◽  
Vol 33 (2) ◽  
pp. 65-78 ◽  
Author(s):  
Eran Friedler ◽  
David Butler

Results from two surveys in S.E. England are used to illustrate and quantify the inherent uncertainty in the quantity and quality of domestic wastewater at the fundamental level of discharges from domestic appliances. The uncertainties in three principal areas are elucidated. Volumetric discharges are shown to vary significantly for several appliances particularly when used in “running to waste” mode. Pollutant load also varies and information is presented for a number of different appliance-pollutant combinations. The frequency of use is known to vary throughout the day, but figures are presented to quantify the extent of the spread of the data during each hour of the day. A means of integrating the various elements of uncertainty is proposed. Quantification should enable better control of treatment plants and improve forecasting of the influence of combined sewer overflows on receiving waters, hence enhancing the management of the associated risk.


1997 ◽  
Vol 36 (8-9) ◽  
pp. 355-359
Author(s):  
L. Fuchs ◽  
D. Gerighausen ◽  
S. Schneider

For the city of Dresden a general master plan was set up based on investigations of the hydraulic capacity of the sewer system, the loads from combined sewer overflow and the treatment plant. The total emission from combined sewer overflows and treatment plant was the main criteria for the analysis of the efficiency of different renovation alternatives. The effect of the different alternatives on the quality of the receiving waters was investigated with a water quality model and evaluated with different approaches.


1990 ◽  
Vol 22 (10-11) ◽  
pp. 163-171 ◽  
Author(s):  
J. Seager ◽  
R. G. Abrahams

Intermittent discharges of storm sewage from combined sewer overflows continue to be one of the principal causes of poor water quality in many urban rivers in the UK. Despite the persistent nature of this problem, very little attention has been given to the study of how discharges of varying magnitude, duration and frequency affect the ecological quality of receiving waters. This information is of critical importance for deriving meaningful water quality criteria for the control of intermittent pollution. This paper describes the results of a study which has been carried out on Pendle Water, a river which flows through the urban catchment of Burnley, Lancashire, UK. Both the chemical and biological quality of Pendle Water are adversely affected by storm sewage discharges during heavy rainfall events. The ecological investigation has been primarily concerned with impact of these episodic discharges on benthic invertebrate communities and physiological responses in fish. Quantitative sampling of macroinvertebrates has indicated that storm sewage discharges may have a significant impact on the structure and diversity of benthic communities in receiving waters. Physico-chemical properties of habitats appear to be altered in a way which tends to favour the proliferation of certain pollution-tolerant species and decrease the abundance of taxa intolerant of organic pollution. Insitu bioassays, including the WRc Mark III Fish Monitor, have been deployed to investigate physiological responses to storm events of different magnitude, duration and frequency. Results are discussed in relation to their application in the field validation of proposed water quality criteria for the control of intermittent pollution from combined sewer overflows.


2017 ◽  
Vol 220 ◽  
pp. 1447-1455 ◽  
Author(s):  
Paul Kay ◽  
Stephen R. Hughes ◽  
James R. Ault ◽  
Alison E. Ashcroft ◽  
Lee E. Brown

1990 ◽  
Vol 22 (10-11) ◽  
pp. 147-154 ◽  
Author(s):  
G. D. Willemsen ◽  
H. F. Gast ◽  
R. O. G. Franken ◽  
J. G. M. Cuppen

From 1985 to 1987, long-term and more or less permanent effects of discharges from combined or separate sewer systems on communities of sessile diatoms and macro-invertebrates in receiving waters have been studied. Sessile diatoms and/or macro-invertebrates have been investigated on 46 locations, spread all over The Netherlands. The results were related to the type of sewer system, the discharges, and the characteristics of the receiving water, and compared with results from sample(s) taken from a corresponding water not influenced by sewer overflows, the reference water. In general, communities of sessile diatoms and macro-invertebrates indicate a more severe organic pollution and disturbance of receiving waters compared with reference waters. In the immediate vicinity of the overflows these communities were more disturbed than at some distance. In small ditches, effects were more pronounced compared with large waterbodies and waters with a constant flow regime. Finally, effects of combined sewer overflows were more pronounced than effects of discharges from separate sewer systems, except for locations in industrial areas.


1996 ◽  
Vol 31 (3) ◽  
pp. 453-472 ◽  
Author(s):  
M. Stirrup

Abstract The Regional Municipality of Hamilton-Wentworth operates a large combined sewer system which diverts excess combined sewage to local receiving waters at over 20 locations. On average, there are approximately 23 combined sewer overflows per year, per outfall. The region’s Pollution Control Plan, adopted by Regional Council in 1992, concluded that the only reasonable means of dealing with large volumes of combined sewer overflow in Hamilton was to intercept it at the outlets, detain it and convey it to the wastewater treatment plant after the storm events. The recommended control strategy relies heavily on off-line storage, with an associated expansion of the Woodward Avenue wastewater treatment plant to achieve target reductions of combined sewer overflows to 1–4 per year on average. The region has begun to implement this Pollution Control Plan in earnest. Three off-line detention storage tanks are already in operation, construction of a fourth facility is well underway, and conceptual design of a number of other proposed facilities has commenced. To make the best possible use of these facilities and existing in-line storage, the region is implementing a microcomputer-based real-time control system. A number of proposed Woodward Avenue wastewater treatment plant process upgrades and expansions have also been undertaken. This paper reviews the region's progress in implementing these control measures.


1994 ◽  
Vol 30 (1) ◽  
pp. 167-175
Author(s):  
Alan H. Vicory ◽  
Peter A. Tennant

With the attainment of secondary treatment by virtually all municipal discharges in the United States, control of water pollution from combined sewer overflows (CSOs) has assumed a high priority. Accordingly, a national strategy was issued in 1989 which, in 1993, was expanded into a national policy on CSO control. The national policy establishes as an objective the attainment of receiving water quality standards, rather than a design storm/treatment technology based approach. A significant percentage of the CSOs in the U.S. are located along the Ohio River. The states along the Ohio have decided to coordinate their CSO control efforts through the Ohio River Valley Water Sanitation Commission (ORSANCO). With the Commission assigned the responsibility of developing a monitoring approach which would allow the definition of CSO impacts on the Ohio, research by the Commission found that very little information existed on the monitoring and assessment of large rivers for the determination of CSO impacts. It was therefore necessary to develop a strategy for coordinated efforts by the states, the CSO dischargers, and ORSANCO to identify and apply appropriate monitoring approaches. A workshop was held in June 1993 to receive input from a variety of experts. Taking into account this input, a strategy has been developed which sets forth certain approaches and concepts to be considered in assessing CSO impacts. In addition, the strategy calls for frequent sharing of findings in order that the data collection efforts by the several agencies can be mutually supportive and lead to technically sound answers regarding CSO impacts and control needs.


1992 ◽  
Vol 26 (5-6) ◽  
pp. 1295-1304 ◽  
Author(s):  
C. Jefferies

Visible pollution discharged from two combined sewer overflows were studied using passive Trash Trap devices and the UK Water Research Centre Gross Solids Sampler. Relationships are presented for the number of visible solids and the mass of gross solids discharged during an event. The differences in the behaviour of the overflow types are reported on and they are categorised using the Trash Traps.


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