A growing majority of the world’s population lives in cities. Urban systems are complex, including interactions between tightly connected human and natural systems both within city boundaries and between cities and the surrounding rural environment. Understanding how cities function is critical to monitoring, managing and improving the urban environment and the environment of the entire globe. The urban environment is also highly heterogeneous, often including striking disparities in the living conditions of and environmental quality experienced by the urban population. Understanding the causes of these disparities, and working towards improving the health, economy and living conditions for disadvantaged populations is a critical challenge in urban systems. The Earth Talks series on Urban Systems Science will bring a series of leading researchers engaged in this increasingly important area of earth, environmental and social sciences research.
Abstract:
Many of our older urban areas have undergone multiple phases of development over the course of several hundred years. Topography has been heavily modified; subsurface infrastructure has been constructed, often piecemeal over time; and the cities that result bear no resemblance to the predevelopment landscape. Urban development has resulted in the compaction of soil, which changed soil porosity and reduced the ability of water to infiltrate into the soil. Estimating the amount of runoff entering stormwater pipes and stormwater control measures (SCMs) requires models that can adequately capture the amount of rainfall that becomes runoff and the amount that infiltrates into the soil and does not enter the stormwater system. This research study combines field measures of compaction, long-term soil moisture sensing, and stormwater runoff modeling in a demonstration watershed to improve understanding of the impacts of a compaction layer (soil resistance > 2,000 kPa) on the amount of water that will infiltrate. The results show that the compaction layer will delay the movement of water into the lower layers of a soil profile and that delay may be a function of rainfall intensity and/or rainfall depth. The modeling highlights the impacts of limited soil infiltration. For a flooding storm (120 mm in 87 minutes), increasing the depth to the compaction layer from 3 cm to 8 cm reduces the amount of time the node is flooded by 50% and the maximum flood depth from 0.61 m to 0.15 m. This research highlights the vital importance of soil compaction layers in understanding the movement of stormwater in the urban environment.
Bios:
Shirley E. Clark, Ph.D., P.E., has impacted the field of water resources engineering through the integration of her research, teaching, and service in order to foster stronger relationships between higher education and society. She serves on the faculty of the Pennsylvania State University Harrisburg, where she was the first female faculty member in the School of Science, Engineering, and Technology’s 50-year history to rise through the ranks from Assistant Professor to Professor. She currently serves as the Acting Director of the School. In 2016, she was recognized with the College Research Award. While at Penn State Harrisburg, she has taught 20 different courses in environmental engineering, ranging from hydrology to risk assessment and has directed the graduate environmental programs for 8 years. She has published more than 100 journal articles, books, chapters, research reports, and conference proceedings. Beyond Penn State Harrisburg, she has provided extensive service to the Environmental and Water Resources Institute (EWRI/ASCE). She currently serves as President of EWRI and Vice President of the Central Pennsylvania ASCE Chapter.
James G. Hunter, Ph.D. is Interim Chair and Associate Professor in the Department of Civil and Environmental Engineering at Morgan State University. His current research interests include urban stormwater management and decision support for green infrastructure, environmental finance, and climate adaptation strategies. His previous research includes several funded projects with Maryland SHA and the Mid-Atlantic Transportation Sustainability – University Transportation Center (MATS-UTC), including studies that support state DOT compliance with water quality regulations and mitigating environmental impacts stemming from highway infrastructure. He is currently a lead investigator for the Baltimore Social-Environmental Collaborative (BSEC), a Department of Energy (DOE)-sponsored Urban Integrated Field Laboratory (UIFL), and the NOAA-sponsored Mid-Atlantic Regional Integrated Sciences and Assessments (MARISA), which of both promote equitable climate solutions and improving the adaptive capacities for community stakeholders in Baltimore, MD. He was also an author for the Northeast Chapter of the Fifth National Climate Assessment (NCA5) of the US Global Change Research Program (USGCRP) which was released in November 2023. Additionally, Dr. Hunter is actively involved in various local, regional, and national technical committees focused on stormwater management, environmental sustainability, and climate resilience. He obtained his Ph.D. and MS in Civil Engineering from Purdue University and BS in Civil Engineering from Morgan State University.
The in-person seminar will be held at John Hopkins University.