Water Resources Research Act Program

Details for Project ID 2016WI354G

Detection of sewage contamination in urban areas of the Great Lakes

Institute: Wisconsin
USGS Grant Number: G16AP00197
Year Established: 2016 Start Date: 2016-09-01 End Date: 2019-08-31
Total Federal Funds: $240,000 Total Non-Federal Funds: $250,510

Principal Investigators: Sandra McLellan, Steve Corsi

Abstract: Urbanization of coastal watersheds impacts our water resources, particularly around the Great Lakes, which serve as a drinking water source for 40M people. Strict regulations prohibit the release of untreated sewage into surface waters, but our laboratory and others have documented that unrecognized (and unregulated) sewage release is widespread and chronic in the urban environment and can be attributed to failing infrastructure and illicit connections. Few approaches and tools exist that can assess these problems and allow water resource managers to identify major infrastructure failures. The overall goal of this project is to improve assessment of failing infrastructure and to measure the impact it has on water quality. The EPA estimates that 271 billion dollars is needed over the next 10 years to maintain wastewater infrastructure to address public health problems. In recent years, Congress has appropriated only about 14% of what is needed. There is evidence that sewer infrastructure is already failing. Our laboratory has found that nearly 30% of local stormwater outfalls have evidence of sewage contamination from illicit connections or infiltration from leaking sanitary sewer lines. The physical location of breaches in the system are difficult to locate, as terminal stormwater outfalls connect to a web of pipes that cover tens of miles in a typical sewershed. We are tackling this problem from the science, technology, and policy angles, which is what will be required to produce outcomes that actually improve water quality. On the science side, we have been working with USGS on the long-term goal of identifying optical signals that correlate to human-specific bacterial indicators, thereby creating a field based, real-time assessment tool. Our laboratory specializes in identifying alternative indicators. Human and animal microbiomes have many organisms that are host specific, and tracking these organisms in the environment provides a signature of the fecal pollution source. Unlike E. coli or enterococci that are general indicators common to almost all warm-blooded animals, alternative indicators have distinctive host patterns. Alternative indicators are extremely sensitive, and can be detected at 4-5 orders of magnitude higher concentrations compared to other constituents in sewage such as pathogens, pharmaceuticals, or personal care products. Our partners at USGS are the heavy hitters on the technology side, and Co-PI Steven Corsi has worked for the past several years to develop an optical sensor that can detect untreated sewage. We have been partners in this work using one of our alternative indicators to identify optical signals that correlate with sewage. The work proposed here is the logical next step in this ongoing collaboration. Importantly, this work is supported by funded work with USGS serving as the lead organization to determine the baseline correlations between organic carbon signals in rivers and pathogens, pharmaceuticals, personal care products. Our proposed work enhances existing USGS studies by adding analysis of alternative indicators for use as an independent measure of sewage sources. The objectives of this proposal include refinement of the field-based technology for up-the-pipe investigations in stormwater systems and support of the development of an in-stream optical sensor (the majority of effort on this project). We are also deeply involved in the policy and management angle of this problem and have built relationships with the two largest municipalities in our basin; this project will build capacity for these entities through specific activities and transfer of knowledge. This work is applicable to urbanized areas nationwide, and could be extrapolated to other watersheds. Overall, this project offers an opportunity to integrate microbial ecology research with ongoing USGS studies to answer new questions about the amount of untreated human sewage entering Lake Michigan from watersheds and develop an assessment tool for water resources managers.