Low Impact Development Requires High Impact Policy

Abstract

Our relationship with rain is complicated. It is imperative for life, yet it wrecks havoc on many of our urban areas. Increased development translates to increased impervious surfaces within cities, resulting in flood damage to property, nearby stream channel erosion, high pollutant loads carried to waterways, and significant damage to aquatic ecosystems. The impacts of rainfall from as small as 1-year and 5-year storm events is magnified due to our development practices and traditional stormwater management infrastructure. Directing huge volumes of runoff as quickly as possible into aging and deteriorating gray infrastructure (culverts, pipes, tunnels, and tanks) is no longer adequate. Green Infrastructure and Low Impact Development embody a new attitude toward managing runoff. Ironically, the fundamental principles are ancient: allow rain to naturally infiltrate the ground where is falls. Green Infrastructure (GI): “An interconnected network of undisturbed natural areas and open space that helps preserve the values and functions of our watersheds and provides a wide array of benefits to both people and wildlife” (Benedict & McMahon, 2006). Low Impact Development (LID): “a comprehensive land planning and engineering design approach with a goal of maintaining and enhancing the pre-development hydrologic regime of urban and developing watersheds” (Low Impact Development Center Inc., 2011). Stormwater management in its most basic terms is simply the way we ease the impacts of our land development processes. For the most part, the primary focus has been on mitigating increased runoff velocity and quantity once a site has undergone disturbance through a change in land use. A shift to preventing negative impacts, rather than mitigating them, is beginning to take precedent using GI and LID measures as preferred stormwater management techniques. However, development incorporating GI and LID remains marginal in most U.S. cities due to conflicting and unsupportive regulatory requirements at all levels of government. This paper aims to provide a comprehensive account of federal, state and local policies encouraging and/or obstructing GI and LID adoption for stormwater management in most urban areas. Causes for intolerant vs. accommodating policy environments will be discussed, in addition to providing a glimpse of impending regulatory updates expected in the next several years. Lastly, case studies will examine a range of policies and programs impacting stormwater in three cities (Atlanta, Chatham County/Savannah, and Philadelphia), profiling each municipality’s approach to advancing the use of GI and LID practices within their jurisdiction.