Combined sewer overflow over an oblique weir at Rat Creek in Edmonton, Alberta

2010 ◽  
Vol 37 (3) ◽  
pp. 477-488
Author(s):  
Elizabeth Valentine ◽  
Kurt Kronebusch ◽  
David Z. Zhu ◽  
N. Rajaratnam ◽  
Sid Lodewyk ◽  
...  
Keyword(s):  
Urban Drainage ◽  
Combined Sewer Overflow ◽  
Rating Curve ◽  
Flow Conditions ◽  
Sewer System ◽  
Sewer Systems ◽  
Model Study ◽  
Combined Sewer ◽  
Sewer Overflow

Oblique weirs are commonly used in urban drainage systems to remove excess flow from a sewer, in particular, a combined sewer system that has limited conveyance capacity. It is important to understand the hydraulics of these weirs to properly monitor the amount of the overflows as well as to design and improve sewer systems. The Rat Creek structure in Edmonton, Alberta, is a combined sewer overflow structure with a weir at an oblique alignment to the centerline of the sewer. A physical model study of the structure was conducted. The results show that both the approach flow conditions and the chamber geometry can significantly affect the hydraulic performance of the weir and invalidate the application of standard weir equations. A unique flow regime with a linear head–discharge rating curve was observed. The effects of modifying the weir and the hanging baffle wall downstream of the weir were also studied and reported. The results of this case study help to improve the understanding of the hydraulics of oblique weirs in sewer systems.

Sediment transport under dry weather conditions in a small sewer system

1998 ◽  
Vol 37 (1) ◽  
pp. 155-162
Author(s):  
Flemming Schlütter ◽  
Kjeld Schaarup-Jensen
Keyword(s):  
Sediment Transport ◽  
Field Data ◽  
Field Measurements ◽  
Weather Conditions ◽  
Sewer System ◽  
Transport Models ◽  
Sewer Systems ◽  
Combined Sewer ◽  
Initial Results

Increased knowledge of the processes which govern the transport of solids in sewers is necessary in order to develop more reliable and applicable sediment transport models for sewer systems. Proper validation of these are essential. For that purpose thorough field measurements are imperative. This paper renders initial results obtained in an ongoing case study of a Danish combined sewer system in Frejlev, a small town southwest of Aalborg, Denmark. Field data are presented concerning estimation of the sediment transport during dry weather. Finally, considerations on how to approach numerical modelling is made based on numerical simulations using MOUSE TRAP (DHI 1993).

Real Time Control in Part of Copenhagen

1993 ◽  
Vol 27 (12) ◽  
pp. 209-212 ◽  
Author(s):  
Jørgen Jens Linde-Jensen
Keyword(s):  
Real Time ◽  
Storage Capacity ◽  
Combined Sewer Overflow ◽  
Real Time Control ◽  
Sewer System ◽  
Time Control ◽  
Combined Sewer ◽  
Sewer Overflow

The application of real-time control to the sewer system in a district of Copenhagen is described. It enables the storage capacity of the sewer system to be better utilised, thus minimizing combined sewer overflow pollution.

Methods to accompany and evaluate planning of combined sewer overflow treatment concepts for complex sewer systems

2014 ◽  
Vol 9 (1) ◽  
pp. 1-8 ◽  
Author(s):  
K. Klepiszewski ◽  
S. Seiffert ◽  
M. Regneri ◽  
E. Henry
Keyword(s):  
Expert Knowledge ◽  
Management Strategies ◽  
Treatment Strategies ◽  
Combined Sewer Overflow ◽  
Simulation Tools ◽  
Sewer Systems ◽  
Combined Sewer ◽  
Treatment Concepts ◽  
Sewer Overflow ◽  
Local Emissions

Simulation tools are in common use to evaluate combined sewer overflow (CSO) treatment concepts in complex sewer systems. However, the planning of CSO structures in a sewer system is a matter of local constraints, expert knowledge and trial and error. Common standards only provide general recommendations to plan CSO structures and work out management strategies. Additionally, modelling the emissions of complex sewer systems tends to result in comprehensive findings. Although, it is essential to understand local behaviour and interaction of CSO structures in a system to improve local and overall performance there is a lack of tools to illustrate comprehensive simulation results in a simple way. In this context the methods presented here are developed. These include clear illustrations of the as-is state in the catchment using Sankey diagrams to show relevant volume and pollutant flows. Furthermore, loading and treatment indicators are suggested to illustrate local loading conditions and treatment capabilities of CSO structures in relation to the overall system. Additional emission indicators provide information on local emissions and show interactions of CSO structures. The results indicate that the suggested methods contribute to an efficient evaluation of interactions and performances to improve treatment strategies in the planning phase.

DESIGN OF STORMWATER INFILTRATION FOR REDUCTION OF COMBINED SEWER OVERFLOW (CSO)

1994 ◽  
Vol 30 (1) ◽  
pp. 53-61 ◽  
Author(s):  
C. O. Rosted Petersen ◽  
P. Jacobsen ◽  
P. S. Mikkelsen
Keyword(s):  
Optimal Solution ◽  
Combined Sewer Overflow ◽  
Return Periods ◽  
Sewer System ◽  
Impervious Area ◽  
Combined Sewer ◽  
Sewer Overflow ◽  
Applied Design ◽  
Design Return Periods ◽  
Stormwater Infiltration

Stormwater infiltration is a significant tool for combined sewer overflow abatement because it involves a decrease in the impervious area connected to the sewer system. When allowing the infiltration structures to overflow into the existing sewer it is shown that for a required reduction in CSO-volume there exists an unambiguous relation between the infiltration structure volume and the size of impervious area connected to infiltration. Further, the presence of an optimal solution minimizing the total trench volume is pointed out. For a Danish sewer system with a travel time of 30 min and an interceptor capacity of 0.2 μm/s the optimal solution for reducing the CSO-volumes by 40 percent involves connecting 65 percent of the impervious area to infiltration trenches with a total storage volume of 3.6 mm. This corresponds to designing the trenches according to an exceedence return period of 0.04 yrs compared to the commonly applied design return periods of 2 to 10 yrs.

Urban Drainage Systems: Design and Operation

1993 ◽  
Vol 27 (12) ◽  
pp. 31-70 ◽  
Author(s):  
J. Marsalek ◽  
T. O. Barnwell ◽  
W. Geiger ◽  
M. Grottker ◽  
W. C. Huber ◽  
...  
Keyword(s):  
Sewage Treatment ◽  
Systems Design ◽  
Urban Drainage ◽  
Sewer System ◽  
Drainage Systems ◽  
Planning And Design ◽  
Sewer Systems ◽  
Combined Sewer ◽  
Urban Drainage Systems ◽  
Receiving Waters

Design and operation of urban drainage systems are addressed in the context of the urban water system comprising drainage, sewage treatment plants and receiving waters. The planning and design of storm sewers are reviewed with reference to planning objectives, design objectives, flows and pollutant loads, sewer system structures and urban runoff control and treatment. The discussion of combined sewers focuses on hydraulic design of combined sewer systems, including combined sewer overflow (CSO) structures, and the use of CSO structures and storage in control of CSOs. The section on operation of sewer systems focuses on real time control, its feasibility, planning, design, operation and applications. Sewer system planning and design are generally conducted using computer modelling tools and procedures which are reviewed in the last section. A brief listing of selected models focuses on internationally used models. Finally, it was concluded that further improvements in environmental and ecological protection of urban waters is feasible only by consideration of urban drainage systems in conjunctions with sewage treatment and water quality in the receiving waters.

Sign in / Sign up

Export Citation Format

Share Document