Assignment #6

Review Article
1) Article Reference
Behera, P, Papa, F., Adams, B (1999) “Optimization of Regional Storm-Water Management Systems” Journal of Water Resources Planning and Management, 125(2) pp. 107-114

2) Summary
The paper discusses the application of optimization methods for storm water management systems. As new lands are being occupied, land developers and municipalities have to deal with runoff quantity and quality control. One of the most common solutions adopted are the implementation of detention ponds followed by a number of Best Management Practices available nowadays. In this case, the detention ponds referred as storm water management (SWM) ponds are considered to control both quantity and quality for a given catchment.
To support finding the best alternative for this projects, optimization using dynamic programming is used to find the best design parameters such as storage volume, release rate and pond depth. The objective is to minimize the costs of implementing the SWM ponds in each of the catchments. The authors consider costs related to the value of land, construction, and operation, maintenance and repair. The decision variables are the active storage volume of the pond, controlled release rate of the pond, and pond depth.
The system constraints are based on two major categories: Runoff Control Performance and Pollution Control Performance. The runoff model inputs statistical meteorological data and transform to runoff considering catchment hydrology and control systems hydraulics. The pollution control is modeled considering the average annual fraction of suspended solids removed from the SWM pond.
The constrains and the conceptual models for the optimization of SWM pond design for single catchment are explained as well as the previous work done in the area and the assumptions made. For the multiple parallel catchments the authors also present an specific model, with a optimization function and constrains for pollution control and runoff. Some details about the computations are also provided.
The authors concludes that is possible to optimize SWM ponds using dynamic programming and to achieve optimal design criteria’s considering single catchment and multi-catchment systems with water quantity and quality aspects. They also suggest different uses such as planning activities, preliminary design and scenario analyses.

3) Discussion
I personally enjoyed more this paper than the other previous two. Maybe because I am more familiar with the conceptual models of storm water systems and I actually find this area more interesting. One thing that really surprised me was to realize that the first author of the paper is a graduate student of the civil engineering department like us. As this is the first of this kind we are dealing I still haven’t completely understood the paper. I´m hoping to clarify it better on the class discussion on Wednesday. See you guys there…