1.1 Overview—Wildfires pose a significant risk to water utilities as they can cause contaminants of concern to be released into surface water and groundwater supplies (1).2 This can endanger human health if systems were not designed to manage these contaminant loads.

1.2 Purpose—Mitigation measures of wildfire effects on sediment loads, trace minerals, and contaminants of concern on runoff in a Source Water Protection Area (2) is an expanding area of study that does not have a full set of regulations at the federal or state level. This guide provides public-sector and private-sector land managers and water utility operators details on how to assess the potential impacts of wildfires on watersheds and measures that can be employed to minimize or abate those impacts prior to a wildfire occurring or after it occurs.

1.3 Objectives—The objectives of this guide are to identify the risks of a source watershed o forest to wildfire and identify actions that can be taken to manage those risks. The guide encourages users to set priorities based upon their associated risk. The guide encourages the us to develop long-term solutions for future wildfire risks.

1.4 Limitations of this Guide—Given the different types of organizations that may wish to use this guide, as well as variations in state and local regulations, it is not possible to address all the relevant circumstances that might apply to a particular area. This guide uses generalized language and examples for the user. If it is not clear to the user how to apply standards to their specific circumstances, users should seek assistance from qualified professionals. Risks may vary depending on the entity evaluating the risk. This guide does not take a position on the causes or science of extreme weather, natural disasters, or changing environmental conditions.

1.5 The guide uses references and information from many cited sources on the control, management, and reduction of pre- and post-fire impacts.

1.6 Several national and international agencies served as sources of information on existing and anticipated levels and management of wildfire risks to drinking water supplies including: the Water Services Association of Australia; the U.S. Department of Agriculture; the U.S. Environmental Protection Agency.

1.7 This guide recommends reference to current regulatory information about risks gathered from various state agencies, such as departments of environmental protection and water resources boards.

1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Adaptation and resiliency measures, however, may be consistent with, and complementary to, other safety measures.

1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.