Stormwater Management
DocumentsDate added
Authors
Faram, M.G. and Kane, A.S.
Abstract
In recent years, with the rising profile of 'sustainability' in the planning equation, various environmentally-conscious, and often, novel approaches to stormwater management have emerged. These approaches, which have included 'hard engineered' and 'soft engineered' techniques, have become increasingly applied, providing options to cover a range of types of situation.
As with any new set of methods or approaches, a major challenge has been to break down the barriers and address the concerns held, in particular, by those who might ultimately become responsible for their operation. This is an ongoing process. The paper discusses the application of innovative 'hard engineered' stormwater management techniques, and their suitability for use either in conjunction with, or in isolation from alternative 'soft engineered' structures.
It is found that these techniques, far from being 'new and unknown' have been extensively applied, and have also been the subject of numerous verification studies, demonstrating their effectiveness and fitness for application.
EVOLVING METHODS FOR THE CALIBRATION OF FLOW CONTROLS FOR STORMWATER AND WASTEWATER MANAGEMENThot!
09/26/2006
Authors
LeCornu, J.P. and Faram, M.G.
Abstract
The ability to accurately and reliably control flows in drainage and sewerage systems is critical for the effective operation of such systems. The use of inaccurate or unreliable flow controls can lead to adverse effects including flooding. Conventional methods for the calibration of flow controls are time consuming and can suffer from poor repeatability.
This paper describes work carried out with the aim of developing new, improved methods, to both enhance accuracy and improve repeatability, while also reducing test times. In order to achieve the objectives, a PROFIBUS based instrumentation and control system was fitted to existing hydraulic test facilities, operated by Hydro International. The new methods, applied to the calibration of vortex flow controls and orifice plates, show potential to reduce test times by a factor of more than ten, while also increasing the accuracy and repeatability of results.
Authors
David A. Phipps, PhD, Rafid M. Alkhaddar, PhD, James Dodd, Michael G. Faram, PhD, Pamela J. Deahl, P.E.
Abstract
With the objective of reducing the polluting impact of urban run-off on receiving watercourses, various proprietary treatment technologies have evolved, including ‘flow-through’ devices that are designed to intercept and store pollutants such as sediments and floatables for later removal and safe disposal. Frequently, the performance of chambers is stated in terms of ‘ability to remove pollutants from the inflow’, often at discrete flowrates. However, a parameter that is often overlooked is chamber ‘retention efficiency’, the ability of chambers to retain stored pollutants once collected. The paper presents the findings of both simulation and experimental studies of different designs of treatment chamber, focussing in particular on the ‘retention efficiency’ parameter. It is concluded that chambers in which the pollutants storage region is isolated from the main treatment area are likely to be most effective.
Authors
D.A. Phipps, R.M.Alkhaddar, E. Loffill, R.Y.G Andoh and M.G. Faram
Abstract
The factors affecting the overall efficiency for the removal of a solid from an influent stream of water by an HDVS (Hydrodynamic Vortex Separator) have been examined using a combination of solids capture/washout experiments and dye tracer studies. The overall solids removal efficiency of the device is a function of loading rate (overall flow). The efficiency can be considered in terms of the balance between initial capture of the sediment and any subsequent re-entrainment. Tracer studies have shown that a well-designed device offers almost complete separation into a mobile and quiescent zone, with slow exchange between the two. This enhances both sediment capture and its subsequent retention.
Authors
D.S. Jarman, M.G. Faram, D. Butler, G. Tabor, V.R. Stovin, D. Burt and E. Throp
Abstract
Computational Fluid Dynamics (CFD) can be applied to gain insights into most fluid processes and associated phenomena and so presents potential to add value in the analysis of urban drainage systems. This paper presents a review of CFD studies carried out in this field, with the objective of developing an appreciation of how and where it can be applied. Existing work has tended to focus around the analysis of four types of urban drainage structure, including Combined Sewer Overflows (CSOs), storage and attenuation systems, stormwater sediment interceptors and sewerage conveyance structures. Within the respective studies, the prediction of flowfields, particulate behaviour, water surface profiles and Residence Time Distributions (RTDs) are found to form the main focus, and as such, these are considered in most detail in the paper. It is concluded that CFD presents a number of opportunities in urban drainage system analysis, and that the scope of this opportunity will further develop as both computational hardware and software resources become more advanced.
