Temporal Evolution of Green Stormwater Infrastructure Strategies in Three US Cities

Abstract

Over the last several decades, interest in green stormwater infrastructure (GSI) has rapidly increased, particularly given its potential to provide stormwater management in conjunction with other ecosystem services and co-benefits such as urban heat island mitigation or habitat provision. Here we explore the implementation of GSI in three US cities -Baltimore (Maryland), Phoenix (Arizona), and Portland (Oregon). We examine the trends in GSI construction over several decades, highlighting changes in implementation rates and GSI types with concurrent regulatory and economic changes. Additionally, we discuss the implications of these GSI portfolios for ecosystem service delivery in urban areas. Results indicate that Portland's quantity of GSI is approximately ten times greater than the quantity of GSI in Phoenix or Baltimore. However, Baltimore has the most diverse portfolio of GSI types. In Phoenix, regional stormwater policies focused on flood control have led to retention basins being the dominant GSI type for decades. In contrast, Portland and Baltimore both have had substantial changes in their GSI portfolios over time, with transitions from detention or retention basins and underground facilities toward filters, infiltration facilities, and swales. These changes favor increased water quality function as well as provision of other ecosystem services. Additionally, we find evidence that each city followed a different GSI implementation pathway, with Portland's combined sewer overflow program influencing initial development of GSI, while state legislation and regional water quality pressures played a major role in Baltimore's GSI development. By studying the evolution of GSI in these different cities, we can see the variability in stormwater management trajectories and how they manifest in different suites of benefits. We hope that continued research of GSI implementation and performance will identify opportunities for future improvement of these infrastructures.

Changes in event‐based streamflow magnitude and timing after suburban development with infiltration‐based stormwater management

“…Starting in the 1970s, communities began installing stormwater control measures (SCMs) to store and treat stormwater runoff before delivering it to streams (National Research Council, ). Since the 1980s, the types and locations of SCMs installed on the landscape have shifted from large, centralized SCMs focused on storing and detaining stormwater to a wide variety of smaller capacity SCMs distributed across the watershed to manage stormwater closer to where runoff is generated (Hale, ; McPhillips & Matsler, ).…”

Stormwater Ponds in the Southeastern U.S. Coastal Plain: Hydrogeology, Contaminant Fate, and the Need for a Social-Ecological Framework

“…Over the same period from 1970 to today when U.S. coastal populations have risen dramatically, there have been shifts in structural controls used for stormwater management reflecting various regulatory, technological, and economic drivers (Anderson et al, 2002;National Research Council (NRC), 2008;McPhillips and Matsler, 2018). In many cases, conventional stormwater pipes and conveyances discharging directly to receiving water bodies, often termed "gray" stormwater infrastructure, have fallen out of favor due to unintended consequences associated with the drastic alteration of streamflows and water quality (e.g., Walsh et al, 2005).…”

Pluvial flood risk and opportunities for resilience

“…All six cities also have stormwater management programs that utilize green infrastructure but, with the exception of Phoenix, green infrastructure has been employed primarily to meet water quality regulations and is not designed to mitigate flooding from extreme rain (Chin, ; City of Portland, ; Center for Watershed Protection/Maryland Department of the Environment, ; International Code Council, ; Rosenzweig & Fekete, ). In Phoenix, large‐scale green infrastructure like detention ponds was designed as part of a regional flood control program (City of Phoenix, ; McPhillips & Matsler, ).…”