Melissa Keeley

Perspectives on the Use of Green Infrastructure for Stormwater Management in Cleveland and Milwaukee

Green infrastructure is a general term referring to the management of landscapes in ways that generate human and ecosystem benefits. Many municipalities have begun to utilize green infrastructure in efforts to meet stormwater management goals. This study examines challenges to integrating gray and green infrastructure for stormwater management, informed by interviews with practitioners in Cleveland, OH and Milwaukee WI. Green infrastructure in these cities is utilized under conditions of extreme fiscal austerity and its use presents opportunities to connect stormwater management with urban revitalization and economic recovery while planning for the effects of negative- or zero-population growth. In this context, specific challenges in capturing the multiple benefits of green infrastructure exist because the projects required to meet federally mandated stormwater management targets and the needs of urban redevelopment frequently differ in scale and location.

Using Individual Parcel Assessments to Improve Stormwater Management

Abstract U.S. localities facing extreme challenges in meeting unfunded surface water quality mandates are increasingly turning to decentralized stormwater management. Planners, though traditionally removed from stormwater management decision making, possess the land-use management skills to significantly contribute to this effort. This article argues that conditions are currently favorable for U.S. localities to follow the example of many German cities and consider assessing the storm-water burden created by individual land parcels (1) to support public policy that provides incentives to manage storm-water on site, (2) to inform watershed planning efforts, and (3) to increase public awareness of the connections between individual land use choices and regional environmental problems.

The Green Area Ratio: an urban site sustainability metric

The Green Area Ratio (GAR) is an urban site sustainability metric which has been used in Berlin, Germany since 1997 to enhance the urban environment by requiring green infrastructure enhancements on private properties. Following an overview of the principles of the GAR instrument, this paper outlines metric development and implementation procedures in Berlin and then analyses how instrument features might affect its potential environmental, social and economic impacts. Despite identified policy deficits and the lack of adequate outcome monitoring in Berlin, the GAR instrument resonates with the environmental planning needs of many urban communities, including its compatibility with dense urbanism, utilisation of green infrastructure techniques, and an aim toward comprehensive environmental planning.

German experience in managing stormwater with green infrastructure

This paper identifies and describes experience with ‘green’ stormwater management practices in Germany. It provides the context in which developments took place and extracts lessons learned to inform efforts of other countries in confronting urban stormwater challenges. Our findings show that an integrated environmental planning approach helps to balance environmental and urban development. Further, the transformation to a mixed grey and green infrastructure necessitates both a quantifiable long-term goal and a suite of policies to incentivise green infrastructure and support implementation. Finally, public authorities must assume leadership while enabling the participation of stakeholder groups in the transformation process.

Stormwater management: can we learn from others?

While there is considerable amount of literature examining how and why American federal and state governments look for information and ideas, there is considerably less knowledge of how these processes operate at the local level. This is particularly true in the case of how ideas related to sustainable water management policies are found and used by local governments. This article attempts to open this area by examining where, how and to what purpose local agents engage in the transfer of low-impact development policies and techniques. This article is organised around four questions: (1) Is there a basic agreement about the pioneers in stormwater management; (2) Where did agents gather information; (3) Did this involve complex understanding; and (4) What emerged as key obstacles to the transfer and learning processes amongst the local authorities involved in this study?

Assessing methods for predicting green roof rainfall capture: A comparison between full-scale observations and four hydrologic models

To optimize the application of green roof technology, there is a need to quantify stormwater mitigation in advance of green roof construction. This study contributes toward meeting this need by assessing the utility of four hydrologic models for predicting green roof rainfall capture, including the: (1) curve number method, (2) characteristic runoff equation, (3) Hydrological Evaluation of Landfill Performance (HELP V3.9D) model, and (4) Storm Water Management Model (SWMM V5.1). Modeling results were compared to over twenty-four months of observed runoff data, collected between June 2011 and December 2013, from two full-scale green roofs in New York City (NYC). Both the curve number method and characteristic runoff equation had the highest Nash-Sutcliffe efficiency index (NSEI) between modeled and observed cumulative runoff depth per event (NSEI = 0.97) due to parameter calibration requirements, where error was mainly due to variations in green roof antecedent moisture conditions. The HELP model was originally intended for evaluation of a continuous landfill cover. As a result, HELPs inability to account for the non-vegetated areas on green roofs caused underestimation of runoff depth for most events (NSEI = 0.84). Alternatively, the SWMM model tended to overestimate event runoff depth (NSEI = 0.94), thought to be the result of its storage term parameterization. Model assessments point to the need for more robust parameter estimation methods, particularly for inputs that are statistical or difficult to measure directly, to improve pre-development accuracy of green roof performance models.

Retrofitting urban drainage infrastructure: green or grey?

Abstract This paper explores the approaches that London, Glasgow, Washington DC and Philadelphia have taken in responding to urban stormwater and combined sewer overflows challenges. In brief, London has begun construction of a large interceptor tunnel with relatively little attention yet paid to green infrastructure, Philadelphia is pursuing green infrastructure based approaches, and Washington DC and Glasgow are implementing a combination of solutions. The cases illustrate that a diversity of responses are emerging to a common environmental problem in cities around the world.

Summary and Best Practices

This chapter reviews the cross-cutting strategies and provides a set of recommendations for best implementing sustainability in the United States.

Conceptualizing, Planning, and Implementing Sustainability in US Cities

This chapter provides an introduction to the book and sets the context for exploring how US cities are planning for and implementing sustainability. We begin by defining sustainability in the urban context and considering how cities conceptualize their roles in these efforts. Next we discuss the rise of sustainability planning in the United States and how cities then implement these plans. We identify important cross-cutting themes that are integrated throughout the book and which highlight best practices in governance, implementation and results, education and communication, equity, innovation, and the recognition of multiple benefits to sustainability projects. We end with a discussion of the research for this project and how we selected the cities featured in the book.

Urban Green Space

This chapter examines the role of urban green space in its many dimensions. Green space is connected to climate, water, and energy. We explore the many terms and definitions associated with green spaces within the plans which included open spaces, street trees and community gardens, and other variations. We examine how cities are investing in the creation, expansion, or improvement of parks, green spaces, and open spaces. We then turn to efforts to expand the urban forest and tree canopy coverage through tree planting programs. We then examine the rise of community gardens and urban agriculture and how cities are supporting these bottom-up efforts. We discovered that while green space presents multiple benefits to communities, benefits of green space were most frequently framed as environmental rather than economic or social benefits.