ABSTRACT
As was mentioned in the last chapter and in others before it, uncertainty about the effectiveness of low-impact development practices and green infrastructure as stormwater runoff control measures is an area of research focus. In this chapter, the analysis is taken a step further by linking the uncertainty in green infrastructure (GI) effectiveness with uncertainty
CONTENTS
Introduction ...................................................................................................... 71 Background ....................................................................................................... 72 Uncertainty in GI Cost-Effectiveness Predictions ....................................... 74
Variability in Costs ...................................................................................... 75 Variability in Performance ......................................................................... 77 Human Factors ............................................................................................ 82 Weaknesses in Conventional GI Program Analyses .............................. 84
Proposed Methodology for Making GI Decisions ....................................... 86 Overview of LIDRA 2.0 .............................................................................. 87 Parcel and Street Data Upload .................................................................. 88 Selection of GI Types, Locations, and Rates of Adoption ...................... 88 Stochastic Rainfall-Runoff Model ............................................................. 89 GI Life-Cycle Costs, Program Costs, and Uncertainty ........................... 91 Five Steps of Implementation .................................................................... 92
Step 1: Preplanning Data Gathering .................................................... 93 Step 2: Stormwater Management Goal Setting .................................. 93 Step 3: Stakeholder-Facilitated GI Scenario Building ........................ 94 Step 4: Cost-Effectiveness Simulations ................................................ 95 Step 5: Postmodeling Policy Development ......................................... 97
Discussion and Conclusions ........................................................................... 98 References .......................................................................................................... 99
that is inherent in GI costs and municipal implementation programs. The chapter demonstrates that in order to make GI a central component of their infrastructure programs and land use plans, municipalities, water utilities, and other natural resource planners need to better account for such uncertainty. Because GI programs involve landscape-scale assessments and stakeholder participation, traditional infrastructure decision-making processes do not easily apply. Instead, a ‚ve-step modeling approach is outlined that integrates the uncertainties in hydrological, economic, and key stakeholder interests and perspectives to provide the policy makers with information that best enables them to evaluate tradeoffs in risk and cost.
