Coastal No Adverse Impact Handbook

The Association of State Floodplain Managers (ASFPM) and the National Oceanic and Atmospheric Administration (NOAA) have collaborated in producing this handbook. The handbook introduces local officials and concerned citizens to No Adverse Impact (NAI) concepts, and suggests how a coastal community can use the NAI approach to minimize the risks and maximize the benefits of their coastal environments.

No Adverse Impact floodplain management is a "do-no-harm" policy that calls for anticipating the potential negative effects of any development or flood control action on other people, their property, and on the coastal environment itself. The policy encompasses a vision, principles, and tools through which local officials, private land owners, a local community, or a number of adjoining communities can effectively and permanently manage a coastal region.

This handbook explains the No Adverse Impact policy, showing specifically how it applies to U.S. coastlines, and gives examples of ways to mitigate coastal risk without unintentionally causing negative consequences. In seven how-to chapters, NAI techniques are defined and differentiated from traditional planning or response elements, defined as "Basic" (minimum federal requirements) and "Better" (additional state and local activities), and are intended to offer maximum resilience in the face of disaster. The seven "building blocks" for communities to apply the NAI principles are each given dedicated chapters in the report with Basic, Better, and NAI level adaptation strategies. 

These NAI "building blocks" include: hazard identification and mapping; planning; regulations and development standards; mitigation; infrastructure; emergency services; and public outreach and education.

Throughout the report, climate change implications and specific references to sea level rise and increases in the severity and frequency of flooding, storm surges and hurricanes are made within the context of NAI principles and techniques.

In the final chapter, two fictional scenarios provide a more detailed and in-depth exploration of the applicability of NAI concepts for coastal communities. One scenario depicts the decision-making process for a municipal wastewater treatment plant facing extreme storm surge and flooding, and the other a Gulf Coast community susceptible to hurricanes. The report demonstrates the application of the NAI principles and process using these same seven policy response areas. 

The area of interest in this handbook is the coastal zone delineated by a State’s coastal zone management program. Because State coastal zone management areas include all or parts of coastal watersheds, the NAI concepts apply to more than just the tidal wetlands, shorelines, and adjacent lowlands, to also include riverine floodplains within coastal communities.

This coastal-zone handbook expands upon on the concepts explored in No Adverse Impact - A Toolkit For Common Sense Floodplain Management (ASFPM, 2003).


Publication Date: May 2007

Related Organizations:


Resource Category:

Resource Types:

  • Planning guides


Go To Resource