College of Engineering

Kieran Van Sant

College of Engineering

Mechanical Engineering

Faculty Mentor: Dr. Franco Montalto

Civil, Architectural, & Environmental Engineering

Karly Soldner

Co-Mentor

Monitoring Philadelphia’s Rain Gardens to Improve Watering Schedule Efficiency

To manage its urban stormwater, the city of Philadelphia implemented the “Green City, Clean Waters” project in 2011. The city will invest more than 1 billion dollars to construct distributed green stormwater infrastructure (GSI) systems. Rain gardens are one form of engineered GSI where cultivated plants absorb stormwater runoff and prevent pollutants from reaching waterways. The city currently waters the gardens if there have been four dry days even if the forecast for the fifth day calls for rain. Due to the high cost of just a single watering and the increasing number of gardens, the city’s current watering policy will not remain feasible.

The main aspect of this project was to custom-make and install sensors in various rain gardens around the city so as to inform irrigation with field monitoring. Multiple soil moisture sensors were planted in each garden: one in the trough and one at the top. Together with weather and soil infiltration data, the aim is to create a data-driven watering schedule based on climatic activity. The first step is to analyze the wetting and drying rates of the different garden soils. The sensors could help improve the efficiency of green infrastructure irrigation activities in Philadelphia and beyond.

College of Engineering

Bethel Xu

College of Engineering

Civil Engineering

Faculty Mentor: Dr. Franco Montalto

Civil, Architectural, & Environmental Engineering

Ziwen Yu Co-Mentor

Cooling Effect of Irrigation on Green Roofs

Urban impervious surfaces inhibit the infiltration of precipitation, causing stormwater runoff, carrying pollutants into urban water bodies. These surfaces also store incident solar radiation, forming urban heat islands. Green infrastructure such as green roofs are believed to be a natural, effective, and economical strategy for reducing water pollution, while also mitigating the urban heat island effect. The goal of this research was to investigate the environmental performance of the Jacob K. Javits Convention Center, the second most extensive green roof in the United States (6.75 acres), specifically whether green roofs with greater soil moisture have significantly cooler surfaces due to a larger fraction of incident precipitation used for evapotranspiration. Evapotranspiration rates and thermal gradients were measured using thermal imaging and three weighing lysimeters positioned in roof bays subjected varying irrigation frequencies. Initial results showed that increasing the irrigation frequency accelerates the evapotranspiration rates, reducing residual energy flux, and lowering surface temperatures of the green roof.

College of Engineering

Daniel Bolton

College of Engineering

Architectural Engineering

Faculty Mentor: Dr. Seyed Nariman Mostafavi

Civil, Architectural, & Environmental Engineering

Urban Influences on Energy Use

Energy is an important resource and a major expense for businesses and private residences across the country. Understanding how we use our energy is key when making decisions to protect our environment and manage our resources. This study examines site energy use in individual buildings across nine major U.S. cities- Atlanta, Austin, Boston, Chicago, Minneapolis, New York, Philadelphia, Seattle, and Washington DC. The energy use intensity (EUI) data has been collected from energy benchmarking programs in these nine cities. The relationship between energy use and building/urban characteristics including floor area, building age, urban population density at the block level, neighborhood affluence, and regional climate factors is explored. Building, climate, and population data are collected from the United States Census Bureau, Zillow Data, a national weather database, and individual government offices in each city. The influence of these factors on building energy use are analyzed using multivariate regression. The results of this project can be used by government agencies and private corporations to inform energy policy making.