Presentations and Posters

Preparing the Next Generation of Engineers for Decision Making under Deep Uncertainty: Exploring the Pedagogical Role of the Decisions for the Decade Game

June 24, 2024

Conference oral presentation, American Society for Engineering Education (ASEE) 2024 Annual Conference and Exposition, Portland, OR

This analysis aimed to explore the role of a serious game called Decisions for the Decade (D4tD) in teaching students about climate change adaptation and decision making under deep uncertainty within the context of this university’s civil and environmental engineering courses. Students’ self-reported quantitative and qualitative results were analyzed to determine the impact of the game in improving student understanding of and attitudes towards uncertainty and robust decision making for climate change adaptation and planning. Quantitative results implied that students found it difficult to make beneficial decisions as uncertainty increased. Students seemed to be more cautious when making collective decisions compared to individual decisions. This collective risk aversion highlighted the benefits of collective learning and decision making for risk management. From the qualitative results, common themes (such as “Informed Decision Making” and “Risk Preparedness”), common keywords (“flood”, “drought”, “climate”, “uncertainty”), and varying emotions observed in student responses indicated students’ awareness of and growing understanding about uncertainty and robust decision making, and pointed to the social/psychological aspects of playing the D4tD game and making decisions under uncertainty. In conclusion, these results attest to the benefit of the D4tD game as a tool within this university and departmental context to improve student understanding of and attitudes towards uncertainty and robust decision making for climate change adaptation and risk management.

Uncertainty and Decision Making for Community Scale Urban Stormwater Modeling

December 13, 2023

Conference poster presentation, AGU Fall Meeting 2023, San Francisco, CA

Abstract: Stormwater modeling software are increasingly used to plan for and implement long-lasting infrastructure in urban areas. The EPA’s Storm Water Management Model (SWMM) is a well-documented and widely used modeling software. SWMM and other related software, such as PCSWMM, must be calibrated and validated before using them to inform any decisions, and this process must consider the multiple sources of uncertainty in model inputs, model parameters, and model structure. Many models in the literature are calibrated to a single or a few events, but recent research has shown that models calibrated for one set of events will not guarantee good performance of the model under another set of events. Our research demonstrates how different modeling decisions can affect performance of a 1D dual drainage stormwater model in PCSWMM representing storms observed over 2022 in a community in Pittsburgh, PA. Explicit and implicit modeling decisions such as the flow metric of interest, the observed storms used for calibration, the location(s) where the model is calibrated, and the spatial and temporal resolution of rainfall data can introduce hidden uncertainties when planning for stormwater infrastructure. These decisions can be further complicated by the deep uncertainty associated with climate change. We offer suggestions and recommendations for modelers to be aware of and appropriately quantify these uncertainties to support responsible and equitable stormwater modeling under deep uncertainty.

Assessing Performance of an Aging Green Roof in Pittsburgh, PA

August 11, 2023

Conference oral presentation, Environmental & Water Resources Institute (EWRI) Low Impact Development (LID) Conference 2023, Oklahoma City, OK

Abstract: Green infrastructure is increasingly recognized as a potential solution for climate adaptation and flood management in urban areas. Research evaluating and reviewing the performance of green infrastructure, and particularly of green roofs, has highlighted the uniqueness of each installation, and the need for site specific data to draw accurate conclusions for planning and implementation. In this research, we aim to use water balance equations to assess performance of a green roof in Pittsburgh, PA, under the effects of age and climate change, and therefore inform future decision making for green roofs in particular, and green infrastructure in general. We develop a Python model to simulate performance of the Hamerschlag Hall Green Roof on Carnegie Mellon University’s campus. The model uses measurements of precipitation and other atmospheric variables measured on the green roof to estimate evapotranspiration during the periods between storms and to estimate infiltration during storms, and then applies a water balance to estimate runoff. The model is calibrated and validated using data collected for storms observed on the green roof in 2019-2020. Previous research has evaluated performance of the green roof for select storms in 2009-2011. By forcing the calibrated model with time series of precipitation and atmospheric variables representing the storms that were observed in 2009-2011, we will be able to compare observed and modeled performance, attributing differences in performance to the age of the green roof.

Modeling Urban Flood Impacts and Potential Solutions at Community Scales in Pittsburgh, PA

December 12, 2022

Conference oral presentation, AGU Fall Meeting 2022, Chicaco, IL

Abstract: Pittsburgh is one of many cities facing increasing challenges from stormwater flooding, and the corresponding impacts are expected to increase under future climate projections for the Northeast United States. This research aims to model urban flooding impacts and potential adaptation strategies in Pittsburgh to facilitate equitable decision making at community and city levels. Building on previous modeling efforts, this research focuses on modeling at the block scale and community scale to support climate resilient stormwater management in Pittsburgh. Preliminary results focus on the data needed to characterize flows and flooding at the block scale under a 1D SWMM model and a 1D-2D PCSWMM dual drainage model, including details about sewer networks, land elevation and land use, building footprints and road networks. Data collection and validation also highlight the importance of engagement with community groups for model planning and of partnerships with all stakeholders for calibration and validation. Engagement with local community groups dedicated to the support of innovative rainwater stewardship and conveyance strategies is essential in identifying at-risk block scale catchments where focused modeling would be most useful. Similarly, calibration and validation of SWMM/PCSWMM models at the block scale is made possible through monitoring partnerships with local utilities and consultants. The calibrated 1D model is used to assess flows and street flooding under design storms in Pittsburgh. After expanding the current 1D model to a 1D-2D dual drainage model, future work will compare flood risk to assess advantages and disadvantages of dual drainage modeling at the block scale, examine how flood risks are exacerbated under the deep uncertainty of climate change, connect modeled projections to adverse health outcomes from frequent basement flooding, and evaluate potential green infrastructure and traditional infrastructure solutions.

Synthesizing Guidelines and Lessons Learned for Implementation of Riverine Nature-Based Solutions (NBS) near to Transportation Infrastructure

December 12, 2022

Conference oral presentation, AGU Fall Meeting 2022, Chicaco, IL

Abstract: Nature-based solutions (NBS) have become more prevalent alternatives to address the negative impacts facing transportation infrastructure located near to rivers under non-stationarities like climate change. NBS here refers to techniques that use natural materials and natural conditions, including engineered structures that incorporate natural processes and materials. In riverine environments, that is those environments near to, crossing, or otherwise interacting with rivers and their surrounding landscape, NBS provide one way to simultaneously address the risks due to river impacts on transportation infrastructure and the environmental issues associated with transportation infrastructure’s encroachment on rivers. In this research, we synthesize select national and state level documents that provide guidelines for riverine NBS in the United States. These seven documents were developed between 2005 and 2021, including reports for four different states across the U.S. They represent a selection of existing guidelines that can be useful for present and future design, planning and implementation, and monitoring and maintenance of projects incorporating NBS in individual states and across the U.S. This research also focuses on a specific case study, the Trout River Restoration Project in Vermont, highlighting a successful NBS project and the invaluable lessons learned. In this project, more than ten different types of NBS were installed on a reach of the Trout River in 1999, and monitored for a year after installation. Assessment of qualitative and quantitative metrics demonstrated the overwhelming success of this project. The lessons learned from this project’s design process, planning and implementation challenges and solutions, and monitoring and maintenance efforts are beneficial to other projects in this geographic location and elsewhere.

Riverine Nature Based Solutions (NBS) for Climate Resilient Highways and Transportation Corridors

January 11, 2022

Conference poster presentation, Transportation Research Board (TRB) Annual Meeting 2022, Washington, DC

Abstract: Nature based solutions (NBS) refers to the use of natural materials, and natural conditions, along with engineered structures that incorporate natural processes and materials. In the riverine environment, NBS can be used along with traditional, “gray” countermeasures to reduce the risk due to lateral migration of stream channels, stream instability or erosion, and flooding, among other risks to transportation corridors in the riverine environment. Most of these risks are expected to intensify under changing precipitation patterns associated with climate change. In this paper, we discuss different definitions of NBS and strategies that can be installed in the riverine environment. We present a few high-level examples of ways in which popular NBS strategies can increase resilience of highways and other transportation infrastructure. We then describe trends among 92 NBS projects completed in the United States. We categorize 151 strategies used within the 92 NBS projects, based on the strategy’s location in the river channel and the design purpose that each strategy fulfills. Among these NBS projects, we found the number of projects increased over time, and project cost and project size generally increased for more recently completed projects. As NBS grow in popularity, we discuss challenges to NBS project design, planning and installation, and monitoring and maintenance, and potential solutions to these challenges. Future work aims to further examine these trends and highlight other successful and interesting case studies, primarily in conversation with local stakeholders. This paper summarizes the initial results from a synthesis being generated under the DOT Eisenhower Fellowship.

Marissa K. Webber