Straight Pipe and Septic Impacts on Rural Streams

EPA Grant Number: SU836775
Title: Straight Pipe and Septic Impacts on Rural Streams
Investigators: Elliott, Mark
Institution: The University of Alabama
EPA Project Officer: Page, Angela
Phase: I
Project Period: September 1, 2016 through August 31, 2017
Project Amount: $14,994
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2016) RFA Text |  Recipients Lists
Research Category: Sustainable and Healthy Communities , P3 Awards , P3 Challenge Area - Safe and Sustainable Water Resources


Establish a field and lab protocol and a decision support tool for detecting and monitoring septic-system and straight-pipe effluents in rural streams in Alabama: Integrate biological and geochemical tracers, quantify septic wastewater contributions to streams and adapt existing methods for rural streams.


Failing septic systems and “straight pipe” (raw sewage discharges) are common in rural Alabama. One detailed study of unsewered homes in Bibb County found that 35% of septic systems were failing and 15% of homes had a straight pipe. These straight pipes alone would discharge >60,000 gallons of raw sewage containing billions of pathogens, including >300 million Cryptosporidium oocysts and >1 billion Giardia cysts, each day in Bibb County. More troubling is that local stakeholders believe the situation is even worse in poorer rural counties with clayey soil, like Hale County where we will conduct our study. We plan to quantify the contributions of onsite wastewater to both stream baseflow and stormflows and assess the associated influences of soil types (clay soil versus sandy loam soil) in selected areas of Hale County, Alabama. The objectives of this EPA P3 project are: (1) to establish and carry-out field and laboratory protocols and (2) draft and refine a decision support tool for detecting and monitoring septic system and straight pipe effluents in rural streams of Alabama.


We propose to identify and sample streams and use multiple methods to quantify the contribution of straight pipes and failing septic systems through: (1) novel GIS and flow-routing methods to identify field sites impacted by these wastewater discharges; (2) analyzing for multiple biological and geochemical tracers; (3) using statistical methods to discern samples’ similarities/dissimilarities and to classify samples (e.g., Jaccard similarity Coefficient, nonmetric multidimensional scaling, principal component analysis); and (4) adapting methods and findings of the EPA urban stormwater illicit discharge detection and elimination (IDDE) guidance developed by project co-PI Professor Emeritus Robert Pitt for use in rural streams. We propose that targeted surface water sampling and analysis of key chemical and biological constituents across hydrological regimes can be used to detect the influence of failing septic system and straight pipe discharges on streams.

Expected Results:

Phase I focuses primarily on sampling and data analysis. We will also give at least three presentations to local and state-level stakeholders and hope to complete a draft decision support tool. While our long-term goals for this research include substantial water quality and health outcomes, measuring such changes is infeasible given the research focus and length of Phase I. During a possible Phase II, we would work with local water managers to iterate and implement our decision support tool and to conduct workshops on its use.

Publications and Presentations:

Publications have been submitted on this project: View all 3 publications for this project

Supplemental Keywords:

Water Quality, Bacteria, Viruses, Public Health, OWTS, Runoff, Stormwater, Surface Water, Rivers

Progress and Final Reports:

  • Final Report