2012 Progress Report: Prediction and quantification of Combined Sewer Outflows under extreme storm events: Flow dynamics and Reduction of Combined Sewer OutflowsEPA Grant Number: R835187
Title: Prediction and quantification of Combined Sewer Outflows under extreme storm events: Flow dynamics and Reduction of Combined Sewer Outflows
Investigators: Leon, Arturo
Institution: Oregon State University
EPA Project Officer: Hiscock, Michael
Project Period: June 1, 2012 through May 31, 2017
Project Period Covered by this Report: June 1, 2012 through May 31,2013
Project Amount: $265,528
RFA: Extreme Event Impacts on Air Quality and Water Quality with a Changing Global Climate (2011) RFA Text | Recipients Lists
Research Category: Global Climate Change , Earth Sciences - Environmental Science , Aquatic Ecology and Ecosystems , Aquatic Ecosystems , Air Quality and Air Toxics , Water Quality , Climate Change , Air , Water
Combined sewer overflows (CSOs) are a major water pollution source for more than 700 cities in the United States that have combined sewer systems (CSSs). CSOs occur in response to heavy rainfall and/or snowmelt events when the capacity of the storm-sewer system is exceeded or when the flow in the system is highly dynamic even when the system is not full. The overall goal of the proposed research is to develop a model for the accurate prediction and quantification of CSOs especially when the flow in a CSS is highly dynamic (e.g., under extreme flow events). The specific objectives are to: (1) develop a mathematical formulation for all possible cases of overflow discharges (e.g., CSOs) at vertical shafts and near-horizontal outlets under extreme flow events; (2) implement the mathematical formulation of overflows into a state-of-the-art open source (free and open access) transient flow model that can be used in complex CSSs; and (3) validate the overflow discharge framework under highly dynamic flow conditions.
Progress Summary:Up to date (August 01 of 2013), the following list of accomplishments have been achieved;
- The mathematical formulation of common cases of overflow discharges at vertical shafts is under development
- A 3D CFD two-phase flow model is in validation phase;
- The flow recirculation system that will host the hydraulic model of the Portland CSS is under construction and will be completed in 7 weeks.
- The mathematical formulation of common cases of overflow discharges at vertical shafts will be further developed, validated and implemented into state-of-the-art transient analysis program Illinois Transient Model (ITM)
- The 3D CFD two-phase flow model will simulate common cases of overflow discharges at vertical shafts
- Laboratory experiments of overflow discharges under extreme events (Portland CSS) will be conducted in the Multipurpose River Hydraulics Research Facility at O.H. Hinsdale Wave Research Laboratory at Oregon State University.