Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock (LockA locked padlock) or https:// means you have safely connected to the .gov website. Share sensitive information only on official, secure websites.

  • Environmental Topics
  • Laws & Regulations
  • Report a Violation
  • About EPA
Contact Us

Grantee Research Project Results

Final Report: Prediction and quantification of Combined Sewer Outflows under extreme storm events: Flow dynamics and Reduction of Combined Sewer Outflows

EPA 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: Packard, Benjamin H
Project Period: June 1, 2012 through May 31, 2017
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: Earth Sciences - Environmental Science , Aquatic Ecosystems , Air Quality and Air Toxics , Water Quality , Water , Air , Climate Change

Objective:

The overall goal of the proposed research is to get insights on the mechanisms leading to geysering in vertical shafts and provide insights into retrofitting strategies to minimize geysers in stormwater and combined sewer systems. The specific objectives of the project have been refined during the course of the project. The original objectives proposed for this project are: (1) To develop a mathematical formulation for common cases of overflow discharges (e.g., CSOs) at vertical shafts and near-horizontal outlets under extreme flow events; (2) To 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; (3) To validate the overflow discharge framework under highly dynamic flow conditions.

The refined objectives are to: (1) produce violent geysers in an experimental setting; (2) numerically reproduce violent geysers; (3) provide insights into retrofitting strategies to minimize geysers in stormwater and combined sewer systems.

Summary/Accomplishments (Outputs/Outcomes):

We have performed over 500 geyser laboratory experiments and over over fifty 3D CFD numerical simulations of air-water geyser flows.  The key findings are: (1) geysers resembling the characteristics (e.g., few consecutive eruptions within a total time frame of a couple of seconds) of those occurred in actual stormwater and combined sewer systems are produced in a laboratory setting for the first time; (2) the experimental study resulted in a dimensionless relationship to predict eruption height and velocity in vertical shafts as a function of dimensionless air mass flow rate; (3) The geyser intensity (e.g., height) was found to increase with the dropshaft height and the air mass flow rate; (4) the laboratory geysers were reproduced using a three-dimensional numerical model; (5) suggestions on potential retrofitting strategies for minimizing geysers are provided.


Journal Articles on this Report : 4 Displayed | Download in RIS Format

Publications Views
Other project views: All 17 publications 4 publications in selected types All 4 journal articles
Publications
Type Citation Project Document Sources
Journal Article Leon AS. Mathematical models for quantifying eruption velocity in degassing pipes based on exsolution of a single gas and simultaneous exsolution of multiple gases. Journal of Volcanology and Geothermal Research 2016;323:72-79. R835187 (2015)
R835187 (Final)
  • Abstract: ScienceDirect-Abstract
    Exit
  • Other: Harvard-Abstract
    Exit
  • Journal Article Leon, A. S. (2017). Mechanisms that lead to violent geysers in vertical shafts. Journal of Hydraulic Research. Under review. Accepted with minor revisions. R835187 (Final)
    not available
    Journal Article Leon, A. S. (2017), Elayeb I. S., Tang, Y. (2017). An experimental study on violent geysers in vertical shafts. Journal of Hydraulic Research. Under review. R835187 (Final)
    not available
    Journal Article Chegini, T., Phan, M. K. and Leon, A. S. (2017). Three-dimensional numerical modeling of violent geysers in vertical shafts. Journal of Hydraulic Research. Under review. R835187 (Final)
    not available

    Relevant Websites:

    Our violent geyser project

    VIOLENT GEYSERS IN STORMWATER AND COMBINED SEWER SYSTEMS Exit

     

    Illinois Transient Model (ITM)

    Illinois Transient Model (ITM) Exit

    Progress and Final Reports:

    Original Abstract
  • 2012 Progress Report
  • 2013 Progress Report
  • 2014 Progress Report
  • 2015 Progress Report
  • Top of Page

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.

    Project Research Results

    • 2015 Progress Report
    • 2014 Progress Report
    • 2013 Progress Report
    • 2012 Progress Report
    • Original Abstract
    17 publications for this project
    4 journal articles for this project

    Site Navigation

    • Grantee Research Project Results Home
    • Grantee Research Project Results Basic Search
    • Grantee Research Project Results Advanced Search
    • Grantee Research Project Results Fielded Search
    • Publication search
    • EPA Regional Search

    Related Information

    • Search Help
    • About our data collection
    • Research Grants
    • P3: Student Design Competition
    • Research Fellowships
    • Small Business Innovation Research (SBIR)
    Contact Us to ask a question, provide feedback, or report a problem.
    Last updated April 28, 2023
    United States Environmental Protection Agency

    Discover.

    • Accessibility
    • Budget & Performance
    • Contracting
    • EPA www Web Snapshot
    • Grants
    • No FEAR Act Data
    • Plain Writing
    • Privacy
    • Privacy and Security Notice

    Connect.

    • Data.gov
    • Inspector General
    • Jobs
    • Newsroom
    • Open Government
    • Regulations.gov
    • Subscribe
    • USA.gov
    • White House

    Ask.

    • Contact EPA
    • EPA Disclaimers
    • Hotlines
    • FOIA Requests
    • Frequent Questions

    Follow.