Hidden Nutrient Transfers to Urban Aquatic Ecosystems
The Elliott lab focuses on pioneering research that reveals hidden nutrient transfers within urban water systems, uncovering the critical role of aging sewer infrastructure and buried streams in shaping nutrient dynamics. By coupling triple nitrate isotopes (δ15N, δ18O, Δ17O) and with Monte Carlo modeling, the lab disentangles complex pathways of nutrient delivery in urban watersheds and quantifies significant nitrogen fluxes from leaking sewers, as demonstrated in Pittsburgh’s Nine Mile Run watershed. Innovative high-resolution sampling and tracer techniques enable the differentiation of atmospheric and sewer-derived nitrate sources, while event-based hydrologic studies highlight how buried stream networks and urban infrastructure alter storm responses and exacerbate flood risks. Key findings show that sewer-derived nitrogen persists across varying storm sizes and dominates urban stream loads, surpassing contributions from other sources like agriculture. This transformative research informs biogeochemical modeling, stormwater management, and nitrogen pollution mitigation, advocating for infrastructure-sensitive frameworks that address aging systems and buried channels to promote resilient urban watersheds in the face of climate change. Graduate students and funders can engage with this impactful work, which redefines urban nutrient budgets and drives actionable solutions to environmental challenges.
Representative Publications
Divers, M.T., Elliott, E.M., Bain, D.J. (2013). Quantification of nitrate sources to an urban stream using stable isotopes. Environmental Science & Technology. https://doi.org/10.1021/es3024716
Divers, M.T., Elliott, E.M., Bain, D.J. (2014). Sewer-derived nitrogen dominates baseflow in an urban watershed. Environmental Science & Technology. https://doi.org/10.1021/es403405r
Forgrave, R.K., Elliott, E.M., Bain, D.J. (2023). Sewer subsidies from overflows and pipe leaks dominate urban stream solute loads in all storm events. Frontiers in Environmental Science. https://doi.org/10.3389/fenvs.2023.1117809
Forgrave, R.K., Elliott, E.M., Bain, D.J. (2022). Event scale hydrograph responses highlight impacts of widespread stream burial and urban infrastructure failures. Hydrological Processes. https://doi.org/10.1002/hyp.14500
Chung, A.H., Elliott, E.M., Bain, D.J., Thomas, B.F., River, M., Nim, C.J., & Darden, J.A. (2023). Riverine nitrogen source and yield in urban systems. Frontiers in Ecology and Environment. https://doi.org/10.1002/fee.2679