Sustainability analysis of distributed, green stormwater infrastructure

Canning, James Francis

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https://hdl.handle.net/2142/101216 Copy

Description

Title

Sustainability analysis of distributed, green stormwater infrastructure

Author(s)

Canning, James Francis

Issue Date

2018-04-24

Director of Research (if dissertation) or Advisor (if thesis)

Stillwell, Ashlynn S.

Department of Study

Civil & Environmental Eng

Discipline

Civil Engineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Green stormwater infrastructure
• environmental justice
• agricultural runoff
• non-parametric testing
• water-quality trading

Abstract

As urban areas continue to grow in population and density of development, stormwater management has become a higher priority for municipal leaders, civil engineers, and residents. Traditional gray infrastructure, i.e., large, piped conveyance networks, effectively removed stormwater runoff and all its associated problems (especially water quality issues) from urban areas beginning in the early 20th century and was heralded as a public health breakthrough. However, gray infrastructure networks have not kept pace with the growth of cities, resulting in a variety of issues including increased peak runoff flow and volume, flooding, increased pollutant loading, degraded water quality, and enhanced urban heat island effect. Green stormwater infrastructure (GSI) mimics pre-development conditions in urban areas attempting to manage excess stormwater runoff. GSI can take many different forms, but its primary functions are to infiltrate stormwater and treat the water on-site, thus reducing runoff volume and pollutant loading downstream. Rain gardens, permeable pavement, green roofs, bioretention cells, street trees, swales, and grass strips are all examples of GSI. Distributed, green networks can provide additional environmental benefits beyond hydrologic improvements, including economic and social co-benefits. GSI networks present an attractive opportunity for decision makers to achieve necessary hydrologic improvements and possibly provide residents with additional co-benefits. In this analysis, GSI is investigated in several capacities. First, GSI is taken out of its traditional urban context and analyzed in an agricultural setting. ``Agricultural green infrastructure'' is sought after as a potential solution to increasing water quality issues upstream of Des Moines, Iowa, USA, representing similar water quality issues throughout much of the agricultural Midwest. In these areas, heavy fertilizer use on agricultural fields leads to increased nitrate loading in nearby surface waters, presenting a risk locally to people using such water as a source of drinking water. Two main proposals are put forward: 1) a widespread, agricultural green infrastructure buildout is proposed throughout the Raccoon River Watershed (RRW) upstream of Des Moines; and 2) treating the water at a nitrate removal facility is investigated as the centralized, gray approach. Both scenarios theoretically treat the polluted water to a high enough quality to consume as drinking water, but they differ in co-benefits and cost. The distributed, green approach is estimated to cost between \$135 -- \$160 million: maintaining the current new nitrate removal facility costs around \$71 million, but building a new facility can cost up to \$184 million. However, building widespread riparian buffers offers increased employment benefits, improves environmental conditions, and helps address the rural-urban divide spreading throughout the United States. Although agricultural green infrastructure might present a high initial cost, it is still less costly than building a new facility sometime in the future and provides comparatively more benefits. Distributed, green networks can provide significant co-benefits to communities, and these co-benefits are the focus of the second portion of analyses. Specifically, social co-benefits in urban areas are investigated. Many GSI calculators, tools, and frameworks exist to help engineers and planners design GSI projects, and yet the literature does not speak to the inclusion of social co-benefits in these GSI calculators. A qualitative analysis is performed exploring whether 21 GSI calculators, tools, and frameworks mention and/or attempt to quantify social co-benefits. Of these 21 calculators, only five mention social co-benefits, and merely two of these attempt to quantify such benefits. A paradigm shift is suggested, one in which social co-benefits are included at the planning stages of GSI projects to ensure that such benefits are available to people engaging the GSI. One derivative of such social co-benefits is the advancement of environmental justice, defined as the equitable distribution of both environmental ills and environmental benefits, regardless of race, income, or any other socioeconomic quality. Historically, low-income and minority neighborhoods have not been locations for environmental outreach. This trend is statistically analyzed in Chicago, IL and Philadelphia, PA, two national leaders in GSI installation, through regression and non-parametric testing, respectively. Results in Philadelphia indicate that the city seems to be achieving its stated goal of investing in ``environmental justice'' communities, based on median household income and race. Overall, results support the conclusion that open-source data can indeed be analyzed to track environmental justice efforts, an important social co-benefit of GSI installation. GSI is a relatively new concept, but it has already been adopted in cities throughout the entire globe. It offers many benefits beyond those benefits provided by traditional gray infrastructure, and GSI is integral to many cities' long-term improvement plans. The present analyses add to the growing body of knowledge concerning GSI through analyzing GSI in an agricultural context and addressing its potential social co-benefits.

Graduation Semester

2018-05

Type of Resource

text

Permalink

http://hdl.handle.net/2142/101216

Copyright and License Information

Copyright 2018 James Francis Canning

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