ORIGINAL RESEARCH
Full factorial study of pipe characteristics, stagnation times, and water quality
Dienye L. Tolofari,
Sheldon V. Masters,
Tim Bartrand,
Kerry A. Hamilton,
Charles N. Haas,
Mira Olson,
R. Scott Summers,
Md Rasheduzzaman,
Audrey Young,
Rajveer Singh,
Patrick L. Gurian,
Corresponding Author
Dienye L. Tolofari
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Correspondence
Dienye L. Tolofari, 3141 Chestnut Street, Curtis Hall 251, Philadelphia, PA 19104, USA.
Email: [email protected]
Search for more papers by this authorSheldon V. Masters
Environmental Science and Policy Research Institute, Philadelphia, Pennsylvania
Search for more papers by this authorTim Bartrand
Environmental Science and Policy Research Institute, Philadelphia, Pennsylvania
Search for more papers by this authorKerry A. Hamilton
School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona
The Biodesign Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona
Search for more papers by this authorCharles N. Haas
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorMira Olson
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorR. Scott Summers
Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Colorado
Search for more papers by this authorMd Rasheduzzaman
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorAudrey Young
Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Colorado
Search for more papers by this authorRajveer Singh
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorPatrick L. Gurian
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorDienye L. Tolofari,
Sheldon V. Masters,
Tim Bartrand,
Kerry A. Hamilton,
Charles N. Haas,
Mira Olson,
R. Scott Summers,
Md Rasheduzzaman,
Audrey Young,
Rajveer Singh,
Patrick L. Gurian,
Corresponding Author
Dienye L. Tolofari
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Correspondence
Dienye L. Tolofari, 3141 Chestnut Street, Curtis Hall 251, Philadelphia, PA 19104, USA.
Email: [email protected]
Search for more papers by this authorSheldon V. Masters
Environmental Science and Policy Research Institute, Philadelphia, Pennsylvania
Search for more papers by this authorTim Bartrand
Environmental Science and Policy Research Institute, Philadelphia, Pennsylvania
Search for more papers by this authorKerry A. Hamilton
School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona
The Biodesign Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona
Search for more papers by this authorCharles N. Haas
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorMira Olson
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorR. Scott Summers
Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Colorado
Search for more papers by this authorMd Rasheduzzaman
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorAudrey Young
Department of Civil, Environmental, and Architectural Engineering, University of Colorado, Boulder, Colorado
Search for more papers by this authorRajveer Singh
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorPatrick L. Gurian
Department of Civil, Architectural, and Environmental Engineering, Drexel University, Philadelphia, Pennsylvania
Search for more papers by this authorAssociate Editor: Andrew J. Whelton
Funding information U.S Environmental Protection Agency, Grant/Award Number: R836880
Abstract
This study examines the effect of pipe characteristics and stagnation time on nitrification, disinfectant loss, and organic carbon concentrations. Pipe racks consisting of different pipe materials (chlorinated polyvinyl chloride [CPVC], cross-linked polyethylene [PEX-B], and copper), diameters (0.75 and 0.5 in.), and water stagnation times (1 week and 12 hr) were set up in two cities with different disinfectants (chloramine and free chlorine) and different corrosion control (orthophosphate vs. pH/alkalinity adjustment). Copper pipe material had lower residual concentrations relative to plastic pipe in both water systems. In the chloramine system, residual concentrations were lower for smaller-diameter pipes, whereas diameter did not strongly influence residual concentration in the chlorine system. Total organic carbon (TOC) increased during stagnation in the chloramine system. Nitrification was observed in the chloramine system for stagnation times of 1 week and 12 hr, indicating that flushing as frequently as every 12 hr may not be an effective mechanism for nitrification control in building plumbing.
Supporting Information
| Filename | Description |
|---|---|
| aws21204-sup-0001-SupInfo.docxWord 2007 document , 1.1 MB | Data S1. Supporting Information. |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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