Semester

Summer

Date of Graduation

2026

Document Type

Thesis

Degree Type

MS

College

Statler College of Engineering and Mineral Resources

Department

Civil and Environmental Engineering

Committee Chair

Emily Garner

Committee Member

Lian-Shin Lin

Committee Member

Brian Lemme

Abstract

Fecal coliform contamination is a major contributor to surface water pollution in the United States’ (U.S.) waterways, whether from combined sewer overflows (CSOs) (point source pollution), runoff from precipitation and snowmelt (nonpoint source pollution), or exfiltration from aging and failing infrastructure. In addition to fecal bacteria, chloride contamination is also a major, prevalent surface water contaminant impacting U.S. waterways. Chloride contamination is predominantly released into U.S. waterways as nonpoint source pollution, endemic to northern areas that use industrial brine and salt as a form of mitigation for ice accumulation on roadways. The purpose of this research was to investigate impairment of a local urban stream on the section 303(d) list of the federal Clean Water Act and U.S. Environmental Protection Agency’s (U.S. EPA) registry of impaired waterbodies. In addition, a core goal of this study was to evaluate current engineering controls and mitigation techniques in urban stream restoration. The focal point watershed in this study is registered on the section 303(d) list as UNT/Monongahela River RM 99.49. NHD Code: WVM-6.2, locally known as “Popenoe Run.” Popenoe Run traverses through an urban watershed and is surrounded by antiquated and failing sanitary infrastructure, which is suspected of exfiltrating sanitary sewage into Popenoe Run. To assess fecal contamination sources and monitor changes in the contribution of sources to fecal contamination throughout the project, microbial source tracking was implemented via quantitative polymerase chain reaction (qPCR) using previously validated qPCR assays specific to human, canine and avian targets. The investigation established seven sample locations along Popenoe Run within the bounds of construction work zone and downstream of the restoration project. The seven sample sites were sampled collectively on randomly selected days prior, during and post stream rehabilitation. Statistical results delineated that total coliform concentrations did significantly decrease by the post-restoration phase. By comparison, E. coli concentrations did not show the same decrease. E. coli’s concentration remained consistently above the federal and state recreational water criterion throughout the entire study. Contrary to expectations, chloride concentrations significantly increased as the restoration progressed. Additionally, MST techniques confirm human fecal contribution. The proportion of samples with quantifiable concentrations of the human fecal marker were ~11.5% during the pre-restoration phase, ~67.6% during the work-in-progress phase and ~41.7% during the post restoration phase, thus, supporting blackwater exfiltrating from failing infrastructure. No significant difference in E. coli concentration was found between the work area and downstream sites, indicating that fecal contamination sources are spatially distributed along Popenoe Run rather than localized to the restoration area, which limits the ability of localized engineering controls to produce a measurable water quality benefit. Furthermore, the canine target assay showed a strong correlation with E. coli concentrations, while the avian target assay showed no statistical significance. Turbidity was found to influence whether the human fecal marker became quantifiable rather than the magnitude of its concentration, suggesting construction-related turbidity may affect the sensitivity of MST-based exfiltration detection independent of actual contamination levels. These findings suggest that fecal and chloride contamination did not show clear improvement within the study's sampling window, though it remains unclear whether this reflects a limitation of the engineering controls themselves or simply insufficient time for the stream to stabilize following restoration. Continued monitoring paired with predictive transport modeling is recommended to clarify this distinction and inform future Total Maximum Daily Loading standards, mitigation technology, and preemptive infrastructure planning.

Download

Share

COinS