Urban infrastructure, extreme events, and waterborne disease: Improving predictability and equity for urban water futures
High quality water that is healthy for people is essential to sustaining human life and the functioning of any society. In this new project, an interdisciplinary group of UM researchers seeks to increase understanding of the predictive factors that contribute to or cause outbreaks of waterborne diseases across the range of cities globally, including engineering factors as well as human decision-making on various time scales. Waterborne diseases are spurred on by advancing impacts of climate change, including rising sea level and storm surges that can be expected to overwhelm urban infrastructure in coastal cities. Currie is collaborating in a group of 9 University of Michigan researchers across 8 different UM units: SEAS, the Department of Civil and Environmental Engineering, the Institute for Social Research, the School of Public Health, the Taubman College of Architecture and Urban Planning, The LSA Department of Psychology, the School of Nursing, and the School of Medicine.
Sustainability and climate resilience in the city of Detroit
SEAS hosts a Sustainability Clinic in Detroit, described in several news articles from 2021 including this press release on the SEAS website. From that press release: “Its goal: improve the ability of the City of Detroit and nonprofits serving the City to address the impacts of climate change on the natural and built environment, human health, and the city’s finances—while working to enhance sustainability policy and action. The SEAS Sustainability Clinic is made possible through support from The Kresge Foundation, which has committed $1 million in funding over the next three years.” Directed by Kerry Duggan, a SEAS alum, the Clinic serves as a foundation for SEAS faculty to build long-term relationships with nonprofits and communities in Detroit. Several SEAS faculty members are working through the Clinic; one of my roles as Associate Dean for Research and Engagement is to serve as PI on the Kresge funds and to help facilitate this work of SEAS faculty. I also serve on the Detroit Advisory Group for the University of Michigan, charged with supporting U-M’s mission of research, education, and service in partnership with Detroit communities.
Investigating the relationship between urban form and water quality
Prof. Runzi Wang in SEAS leads this collaborative research, in which we are developing new data-science and modeling methods to use existing stream water quality datasets (nutrients and sediments) for streams that pass through U.S. urban areas and link those to specific sub-watersheds. In the sub-watersheds, we investigate metrics of urban form such as spatial patterns and connectivity of impervious surfaces and how they relate to road networks and built structures. We use data-driven modeling to investigate relationships between urban form and its effects, through storm runoff, on stream water quality. We are also developing methods to include other social outcomes that derive from urban form, including housing density and access to green space. The results from this research will have relevance for urban planning, including identifying synergies or tradeoffs in joint outcomes.
This research was selected by the Michigan Institute for Data Science (MIDAS) to receive pilot-study funding through its PODS program (Propelling Original Data Science) in 2020 with a project titled “Data Science Approach towards a Socio-ecological Framework for the Investigation of Continental Urban Stream Water Quality Pattern” — Runzi Wang with co-PIs: Yang Chen and Bill Currie.
NASA OCEAN-funded project to train under-represented students in ocean science
Our research collaboration across 5 universities to study Great Lakes watersheds and wetlands, which we have named GLWEST (Great Lakes Watershed Ecohydrology Science Team), was recently funded by NASA’s Minority University Research and Education Project (MUREP) Ocean Biology and Biogeochemistry, or OCEAN program. Prof. Jason Martina at Texas State University is the lead PI. We will be working in Lake Huron, studying watershed-wetland-nearshore coastal interactions related to nutrient flows from the land to the lake. We developed the CETUP program (Coastal Ecohydrology Training Undergraduate Program), in which 6 undergraduate students per year from the minority-serving institution Texas State University will travel to the Great Lakes region. While in this region they will be trained in watershed and wetland modeling, fieldwork, and remote sensing at the University of Michigan (co-PI Currie), Michigan State University, and the Michigan Tech Research Center in Ann Arbor. Faculty from all 5 universities will also train and interact with the CETUP student cohorts remotely during their time at Texas State, where modules and assignments will cover the basics of research, scientific literature comprehension, aquatic science, remote sensing, data science, and simulation modeling. This project is titled “Integrating Systems Models and Remote Sensing to Explore Aquatic Ecosystem Vulnerability to Global Change in Lake Huron.” See also this link to a SEAS press release about this project.
Modeling wetland function and dynamics with the Mondrian model
Mondrian is a complex process model designed to explore interactions between plant community dynamics (shifts in species composition) and ecosystem processes (N and P cycling, carbon balance, and water levels and flows) in wetlands. It was developed at the University of Michigan, led by Bill Currie. Collaborators in stages of model development over time have included Deborah Goldberg, Jason Martina, Kenneth Elgersma, and Sean Sharp. We originally designed it to explore the ecology of invasive wetland plants — what plant traits, under what environmental conditions, make them invasive in native wetland communities. The model has proven to be useful for exploring a variety of questions in community and ecosystem ecology as well as applied questions related to wetland restoration.
The graph at right shows results from a Mondrian simulation in which NPP (net primary productivity, or annual growth) of a native plant population (open symbols) declines as an invasive plant species (filled symbols) comes to dominate over a period of 10 to 15 years.
We have used Mondrian to better understand the ecology of wetland plant invasions and have worked directly with wetland managers in the Saginaw Bay CISMA (Cooperative Invasive Species Management Area) to simulate management practices and outcomes to remove invasive plants and restore native marsh plants. Current research is proceeding on a number of fronts. With NASA funding, we are working to integrate Mondrian’s processes into a regional-scale hydrogeochemical model with collaborators from Michigan State, to simulate the futures of Great Lakes coastal wetlands under a range of climate, water level, and land-use scenarios. We are using the model to study the potential effects of reducing agricultural nutrient runoff on wetlands (see this news update). Sean Sharp, a postdoc working on the team at Michigan, is exploring the effects of water level, hydroperiod, and water residence time (or hydrologic flushing rate) on N cycling including wetland N retention, removal and denitrification (see our ESA presentations 2019). Graduate student Ye Yuan completed a Master’s thesis using Mondrian to simulate greenhouse gas emissions (CO2, N2O and CH4) in Great Lakes wetlands (with a peer-review paper in review). Undergraduate Abby Meyer recently worked on studying spatial patterns of plant branching and how that effects plant competition in the model. Jason Martina (Texas State University) and his student Ramiro Ramirez are using Mondrian to explore the role of propagule pressure in Phragmites invasions.
From its inception, Mondrian was designed to have a large number of parameters and drivers that can be modified by the user, allowing the model to be applied to a wide range of research questions. We encourage other research groups to download the model and apply it to different wetland sites, different ecological research questions, or to simulate wetland management and restoration actions. See Downloads page for the model, input files, and user guide.
Case studies: Sustainability issues in the Great Lakes region
In my undergraduate teaching I use a case study approach and I’m currently working on developing some research projects that do so. In a case study approach, we begin not by focusing on what is known in a single discipline, but with a complex, often wicked problem defined with broader conceptual boundaries. Large-scale, interconnected problems and issues related to the environment and sustainability typically cross disciplines. A case study approach draws on all of the disciplines needed to understand the complexity of the problem including its past, consideration of its future, and consideration of possible solutions. It seeks to develop a level of integrated understanding specific to the case study.
Listed here are some of the case studies I am currently working on and that I use as teaching cases:
The diversion of Lake Michigan water for the municipal water supply of Waukesha, Wisconsin. Over a century, the city of Waukesha drilled deeper to obtain an increasing water supply as the city grew. Deep water was found to contain radium, a toxic heavy metal, so Waukesha no longer had a safe supply of drinking water. The city falls just outside the Great Lakes basin boundary. The Great Lakes Compact, an agreement between 8 states, disallows diversion of water outside of the basin, but allows for review of special cases. The Compact Council (representing the 8 Great Lakes states) approved a plan in 2016 to divert water from Lake Michigan and return treated wastewater through the Root River.
Lake Erie harmful algal blooms (HABs). Nutrient runoff from row-crop agriculture and CAFOs in the Maumee watershed and others in the Western Lake Erie Basin trigger harmful algal blooms that degrade the lake ecosystem, create a dead zone, and threaten city water supplies. Northwestern Ohio is a highly productive agricultural region, and demand is high for corn, soy, and meat production, including demand from agricultural exports and the use of corn to produce corn-ethanol biofuel.
Enbridge Line 5. This is an oil pipeline that runs through the Mackinac Straits in northern Michigan, resting directly on the lakebed for about 4 miles. An oil spill here would be potentially catastrophic because of the strong currents and large distances that oil could be distributed, harming both natural ecosystems as well as numerous businesses and coastal communities. There are concerns about the aging pipeline, inadequate attention to preventing a spill, and debate about whether a new future tunnel should be placed beneath the lakebed. This case study highlights different views of risk as seen by different stakeholders: environmental risk, business risk, and political risk.
Argo dam in Ann Arbor. Should Ann Arbor remove Argo dam, a hydroelectric dam on the Huron River that is no longer used for electric power? This debate is part of a growing national conversation about the removal of thousands of old dams that no longer serve their original purpose, including many in the Great Lakes region. Argo dam is an interesting case study of differing stakeholder perspectives and local political power. The dam has remained in place, in large part because of a vocal group of rowers that use the reservoir, Argo Pond, created by the dam.
Expansion of biofuels. Corn-ethanol biofuel has risen dramatically in the last 10 years. Researchers in the biofuels industry are working on the development of second-generation cellulosic ethanol that may come from forest trees or plants such as switchgrass, as well as sources of plant oils (including algae) for biodiesel. Biofuels can help the US gain energy independence and energy security and can promote rural livelihoods by increasing the demand for plant feedstocks. However, there are downsides. They compete against food production, produce environmental harm such as nutrient runoff when farmed intensively, and if scaled up could result in widescale land use change and forest loss in the Great Lakes region. In addition, while proponents often assume all biofuels are carbon neutral, this is really a nuanced topic that is the subject of debate in the sustainability community.
The Monarch butterfly. The Monarch is an iconic species with an incredible life history: A large population reproduces in the Midwest during the summer, then over-winters in Mexico, migrating thousands of miles. The population has been in steep, but irregular, decline for over 20 years. The US Fish and Wildlife Service decided that the species merits consideration as an endangered species. The species decline has many probable causes, foremost among them is the loss of milkweed plants from large areas of agricultural land that are treated with glyphosate herbicide. The Monarch story is an example of pollinator declines throughout the US.
Metallic sulfide mining in the Great Lakes region. The Great Lakes region is rich with mineral resources including metals such as copper, gold, silver, nickel, and cobalt, and mining metals is an important part of the region’s historical economic growth. Demands for these metals are continuing to grow. There is a permitting process for opening, operating, and closing mines, and some in the mining industry voice a commitment to using environmentally-friendly practices. Debate continues among different groups of stakeholders over where mining should occur and whether permitting in this region is adequate.
Futures of Great Lakes watersheds and coastal ecosystems
This is a NASA-funded project to link land use, socioeconomic drivers, and climate to the hydrology and water quality in large-river watersheds and the effects on Great Lakes coastal wetlands. In past work, the Michigan team developed the Mondrian model of community-ecosystem processes to better understand the effects of water and nutrient deliveries to the coast on wetland function, including carbon storage, nitrogen retention, and the community ecology of native and invasive wetland plants.
At right: the St. Claire River delta showing wetland plant communities identifed using satellite remote sensing (photo courtesty Laura Chavez at Michigan Tech Research Institute).
We are currently linking the Mondrian model to the Landscape Hydrologic Model developed at Michigan State University, working with collaborators at MSU. Led by collaborators at Michigan Tech Research Institute (MTRI), the team is using satellite data to extend our modeling across the coastlines of the entire Great Lakes basin. (Other collaborators are at Texas State and the University of Northern Iowa.) We will be applying the coupled models to explore the futures of Great Lakes coastal wetlands, including the effects of alternative future scenarios of land use, agriculture, socioeconomic change, and climate change.