Current Members

Donald and Martha Harleman Professor

Margaret MacVicar Fellow

Fellow, American Geophysical Union

ASCE, Hunter Rouse Hydraulic Engineering Award

Chi Epsilon Honor Member

Distinguished Engineering Alumni Award – Bucknell University

18th Harold Jan Schoemaker Award

NSF Career Award

School of Engineering Bose Award for Excellence in Teaching

Samual M. Seegal Prize, MIT – for inspiring student in pursuing excellence

Earll Murman Award for Excellence in Undergraduate Advising

IAHR M. Salim Yalin Lifetime Achievement Award

hmnepf (at) mit.edu

Administrative Assistant

snethert@mit.edu

I’m here to help with purchasing, shipping, website updates, and more for the Nepf Lab. Please reach out with any inquiries!

Postdoctoral Fellow

hpark418@mit.edu

In natural streams, vegetation may grow in spatially heterogeneous patterns of individual patches. Different flow regimes develop near the vegetation, depending on the evolution of wake structure between the patches. The flow regime affects the ecological, biological, morphological processes in aquatic system. My current research focuses on the growth of turbulent flow structures in the gap between patches and on how the wakes interact to develop flow structure over a wide range of scales. Specifically, I am conducting a series of laboratory experiments with submerged flexible vegetation (Rotala indica), in which I will vary the gap between patches. The experiments will identify the patch spatial density (gap spacing) for which there is a transition from heterogeneous near-bed flow, moving around individual patches, to flow structure defined by a vertical shear layer, with uniformly low velocity near the bed.  The result of this study will provide a model to predict real-world fluvial processes such as morphodynamic evolution, flow resistance, and habitat in channels with submerged flexible vegetation patches.

Graduate Student

tianzhao@mit.edu

I am examining sediment transport. In my undergraduate studies, I had field experiences observing suspended cohesive sediment transport on tidal flats. In particular, my trips to coastal saltmarshes in Jiangsu, China, have set me thinking about how marsh plant species like Spartina alterniflora and Spartina anglica will interact with local sediment transport and morphodynamics, and how researchers can integrate vegetation-induced turbulence and drag into sediment transport models. To study these problems, I have started my graduate career in the Nepf Lab in Fall 2018.

Research Affiliate, Nepf Environmental Fluid Mechanics Laboratory, MIT

Research Scientist, Laboratory of Hydraulics, Hydrology and Glaciology (VAW), ETH Zurich

ischalko@mit.edu

Personal Website

Numerous rivers have been confined and are eco-morphologically impaired, resulting in an increased demand for river restoration projects. Wood placements are a common and inexpensive measure for river restoration. To plan and evaluate river restoration projects including wood accumulations, it is important to understand the interactions between flow, wood, and sediment. Using physical modeling, my project aims to quantify flow and morphological structures associated with different wood accumulation setups. The results will be used to develop design recommendations for wood accumulations.

Graduate Student

rbs@mit.edu

I grew up on the East Coast and have spent many summers in the Great Lakes region. It’s easy to take for granted the roles that vegetation play in nature, and view plants as ugly weeds to clear instead of species to protect. Seagrasses provide important habitat, carbon sinks, and other ecological functions, but are threatened by overdevelopment, pollution, and climate change. Long meadows of seagrass have been shown to attenuate currents and attenuate wave energy, but the dynamics of wave damping in the presence of currents are not as well understood. In addition, the morphological characteristics of plants vary widely in scope and in their relative contributions to vegetation-induced drag in oscillatory flow. I plan to investigate these areas to improve our understanding of the complex but ubiquitous interactions between flow and vegetation. Improved models of flow interactions with vegetation can help predict how storms and currents will affect vulnerable meadows, and help design infrastructure and living shorelines to protect coastal areas.

Graduate Student

inhim838@mit.edu

Nature has evolved to know best how to stay resilient against natural forces. My research examines the science of how marshes can be placed in front of seawalls to attenuate wave amplitude and wave energy to reduce over topping and erosion. This is studied using wave dissipation models based on the physics of wave-vegetation hydrodynamic interactions. Hybrid coastal defense strategies not only offers important ecosystem services to combat climate change challenges, but also potentially deliver the same level of coastal protection more economically. Therefore, I will also conduct cost-benefit analysis on combined marshes and seawall infrastructures to examine whether societies would benefit economically from implementing nature based coastal protection and live more harmoniously with the natural environment.

Visiting Graduate Student from Zhejiang University

bingr99@mit.edu

Coastal wetlands are vital ecological resources and significant carbon sinks. However, the global area of coastal wetlands is decreasing at the alarming rate of 0.7% to 7% annually. Current- and wave-driven erosion is a major driver of retreat along wetland leading edges. It is critical to understanding the mechanisms of erosion, so that we can improve restoration and protection strategies to maintain coastal ecosystem. My research investigates the hydrodynamic characteristics and bedload sediment transport in vegetated regions under the combined influence of waves and currents. I use flume experiments and theoretical analyses. I will use the results from the flume experiments to construct sub-grid-scale models to represent turbulence and sediment transport in large-scale, two-dimensional numerical simulations, which can be used to study the evolution of coastal wetlands.

Graduate Student

jvbrice@mit.edu

My research is concerned with the design and implementation of nature-based coastal adaptation in urban settings. Despite increased interest in the incorporation of natural ecosystems in coastal engineering projects, there are still many gaps in our understanding of how these ecosystems perform hydrodynamically under extreme weather conditions and future climate scenarios. Using a combination of physical and numerical experiments, I will investigate wave attenuation and resilience of hybrid coastal defense strategies under various flow conditions, particularly the ability of oyster beds to reduce wave-driven flooding and overtopping during storms. I will then use a coastal-scale hydrodynamic model to explore implementation in an urban study area, with the goal of providing coastal communities with the tools to design physically and ecologically resilient waterfronts. Watch me on the “Ask MIT” Podcast.

Visiting Graduate Student from The Hong Kong Polytechnic University

akiyh@mit.edu

My research focuses on the initiation and evolution of large-scale coherent structures in finite vegetation canopy. Previous studies have shown that large-scale coherent structures can be observed along the patch lateral interface and the patch wake. Different kinds of large-scale coherent structures can be triggered at the same time and perform interaction with each other, further complicate the flow and turbulence structures. I will further investigate the impact of the large-scale coherent structures on the sediment transport.