Toxic Metal Removal By Horizontal Levees That Protect Coastal Infrastructure From the Effects of Sea Level Rise

Project Number
Project Date Range
Funding Agency
National Oceanic and Atmospheric Administration (NOAA)
Focus Area(s)
Resilient Coastal Communities and Economies




This research project will investigate the natural processes that control the removal of toxic metals in horizontal levees, and determine if design can target specific contaminants and prevent them from being a potential source of contamination.



Coastal communities require adaptation measures to minimize their risk from sea level rise and a changing climate. Protection is considered the most feasible approach in urbanized areas with limited space. A horizontal levee is a nature-based wastewater treatment system designed to protect coastal infrastructure from the effects of sea level rise with the added benefits of improving water quality and providing habitat. A horizontal levee relies on microbes in the subsurface to create a distinct redox gradient capable of removing nutrients and pharmaceuticals from treated municipal wastewater and reverse osmosis concentrate (ROC).

This research aims to investigate the biogeochemical processes that govern the immobilization of toxic metals in horizontal levees, and how these systems can be designed to target specific contaminants and prevent them from being a potential source of contamination. The researchers will characterize the levee’s porewater and sediments using conventional quantitative methods and state-of-the-art spectroscopic methods. They will also utilize microcosm experiments and geochemical modeling to inform the material selection, design criteria, and performance lifetime for future applications of horizontal levees targeting specific contaminants.

Involving stakeholders who are familiar with water quality criteria, environmental compliance and urban development ensures that the strategies created by the research team increases the feasibility and accessibility of this technology and supports the development of resilient coastal communities.

Community Mentor: Jeremy Lowe (San Francisco Estuary Institute)


Principal Investigators
David Sedlak
University of California, Berkeley
Co-principal Investigators
Jonathan Uhler
University of California, Berkeley