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The Healthy Forests Initiative and Healthy Forests Restoration Act
Interim Field Guide

Some other factors that could be considered in evaluating the risks associated with wildland fires include the:

  • Vegetation type

  • Predicted fire severity

  • Soil texture

  • Stream gradient

  • Precipitation intensity

  • Surface soil erodibility estimates (using the Revised Universal Soil Loss Equation) and mass failure risks

  • Potential for increases in instantaneous peak streamflows

  • Portion of the water system infrastructure that is within the 100-year floodplain

  • Lands close to the watershed where conditions pose a significant risk from fire

  • Number of people served by the community water system

  • Percent of the municipal watershed area administered by the DOI BLM and USDA Forest Service

  • Probability that the community water system would be disrupted

These evaluations should be performed at the local level, in an open forum including all interested parties as part of the normal NEPA process, before treatment areas are selected.

The HFRA does not require setting priorities among various at-risk municipal watersheds based on the relative risk of damage in the event of wildland fire. Some municipal watersheds are at more risk of fire than others, based on the likelihood of a wildland fire occurring, its potential damaging effects, the amount of Federal land in a condition class that increases the risk from wildland fire, and other factors. Resource managers should consider such factors when allocating funds.

The determination of “significant risk” referred to in HFRA Sections 102(a)(2) and (3) should not be confused with NEPA requirements to determine whether a Federal action will create a “significant impact” on the environment. A determination of significant risk under the HFRA does not dictate whether an agency should use an EA to document an action’s effects.

The HFRA and the Safe Drinking Water Act have specific definitions for the terms municipal watershed and municipal water supply system:

  • A municipal watershed is a community water system “that serves at least 15 service connections used by year-round residents of the area served by the system; or regularly serves at least 25 year-round residents” (Safe Drinking Water Act, Section 1401, 42 U.S.C.A. 300f.(15)).

  • Under the HFRA, a municipal water supply system is “the reservoirs, canals, ditches, flumes, laterals, pipes, pipelines, and other surface facilities and systems constructed or installed for the collection, impoundment, storage, transportation, or distribution of drinking water” (Section 101).

For the purposes of this Field Guide “… in such proximity to a municipal water supply system” (HFRA Sections 102(a)(2) and (3)) would include:

    • Those Federal lands in the municipal watershed drainage area.

    • All Federal lands adjacent to the infrastructure of a municipal water system.

    • A locally determined zone of protection around the perimeter of the municipal watershed that extends into the adjacent drainages. This zone could be delineated during development of a Community Wildfire Protection Plan or through discussions with managers of local municipal water systems. The degree that the zone extends into adjacent drainages, and the width of these extensions should take into account geographic features, the condition of the vegetation, and other characteristics of the adjacent lands.


The analysis and documentation for threats of wildland fire to municipal water supplies and infrastructure under Sections 102(a)(2) and (3) of the HFRA are intended to be integrated with the analysis and documentation done under current NEPA guidance and other relevant guidance. This documentation should be included in the NEPA documents normally prepared during project planning, the Decision Records or Records of Decision prepared before project implementation, or in the project file itself.

This analysis and documentation for the threat of wildland fire referenced above should document the factors considered in determining that a wildland fire likely would have adverse effects on the quality of the municipal water supply or on system maintenance. If possible, when making the case for adverse effects, the hazards and risks should be quantified. The short- and long-term effects of proposed treatments and the effects of taking no action should be described as provided for in the Judicial Review section.

Because of homeland security concerns, and as required by Title IV of the Public Health Security and Bioterrorism Preparedness and Response Act of 2002 (P.L. 107-188), personnel must avoid providing exact locations of water supply systems and associated infrastructure. All maps, information, and data related to these community water supply systems that are used to assess risk and set priorities for fuel treatments are to be exempt from Freedom of Information Act (FOIA) requests and must be stored in secure locations—they are not public documents. For further assistance regarding FOIA questions, contact your local FOIA coordinator.

Threats to Ecosystem Components or Forest or Rangeland Resources

Section 102(a)(4) of the HFRA authorizes expedited vegetation management projects on NFS and BLM lands where any one of three specified conditions is present that poses "…a significant threat to an ecosystem component, or forest or rangeland resource, on the Federal land or adjacent non-Federal land."

Those conditions are:

  • Wind throw, blowdown, or ice-storm damage on NFS or BLM land
  • The existence of an insect or disease epidemic on NFS or BLM land
  • The presence of an insect or disease epidemic on immediately adjacent land (which may be non-Federal land) and the imminent risk that the epidemic will spread

The presence of one or more of these conditions does not trigger use of HFRA procedures. There must be a determination that the condition or conditions pose a significant threat to an ecosystem component or a forest or rangeland resource. For example, a stand where conditions rate a high hazard of loss or damage to an ecosystem component or forest resource would not qualify for HFRA procedures unless there was an actual insect or disease epidemic or other condition listed above. Such stands certainly could be treated to reduce risk using other authorities. In addition, significant threats caused by conditions other than the three conditions listed above do not qualify a project for HFRA authorization.

Note: Projects authorized under Section 102(a)(4) are exempt from the old-growth and large-tree retention provisions in Sections 102(e) and 102(f) of the HFRA. They do not constitute “covered” projects as defined in Section 102(e)(1)(B).

Determination of Significant Threat to an Ecosystem Component or Forest or Rangeland Resource

Examples of important forest or rangeland resources that can be harmed by wind throw, ice-storm damage, or insect and disease epidemics include: water quality and quantity, forest products, critical wildlife habitat, and threatened and endangered species. In addition to directly affecting these resources, epidemics and wind throw also can increase fuel buildups and the risk of destructive wildland fire.

Examples of ecosystem components that can be harmed include: increasingly rare environments such as whitebark pine ecosystems, riparian forests, sky islands, single-storied old forests, critical fish and wildlife habitat, and threatened and endangered species.

Resource managers are responsible for identifying important ecosystem components and resource values that may be threatened by wind throw, ice-storm damage, or insect or disease epidemics, and deciding the management actions that will be taken to address them. Forest health and other specialists, working together with resource managers, should provide expert advice whether a significant threat exists to ecosystem components or forest or rangeland resources.

The determination of “significant threat” referred to in Section 102(a)(4) should not be confused with NEPA requirements in the National Environmental Policy Act of 1969 to determine whether a Federal action may significantly affect the quality of the human environment. A determination of “significant threat” under the HFRA does not dictate whether an environmental analysis or environmental impact statement should be prepared. Rather, that determination should be made after developing alternative treatments and assessing their environmental effects.

Determining Whether Blowdown or Ice-Storm Damage Increases Risk to an Ecosystem Component or Forest Resources

The HFRA provides for expedited processes when wind throw, blowdown (figure 8), or ice-storm damage on NFS or BLM land poses a significant threat to an ecosystem component, or to a forest or rangeland resource, on the Federal land or adjacent non-Federal land.

Photograph of trees blown down in a forested area.
Figure 8—Blowdown on the Superior National Forest increased fuel loadings
and the forest’s susceptibility to insect infestations.

Disturbance events such as ice storms (figure 9), wind events, blowdown, fires, or large-scale droughts, may affect population growth of insects or disease agents. Such events can be a factor triggering massive insect outbreaks. Large areas of blowdown provide a supply of stressed and dying trees where insects may feed and breed. They also can increase the risk of destructive wildland fire.

Photograph of damaged trees in a forested area.
Figure 9—A December 2000 ice storm inflicted moderate to heavy damage
across 340,000 acres of Ouachita National Forest and private lands in Arkansas.
Damaged trees were more susceptible to insect and disease infestations,
and fuel loads increased the risk of catastrophic wildland fire.

Ice storms or wind events knock down or damage trees that increase wildfire risk and often are colonized by insects, leading to rapidly increasing insect populations that can attack surrounding trees, if they are susceptible. Areas of scattered blowdown can result in insect epidemics in areas with moderate-to high-hazard conditions.

Assessing whether a particular wind throw or ice-storm event poses a significant threat to an ecosystem component or forest or rangeland resource is complex and depends on the specific ecological conditions and the context in which they occur. Some of these factors are discussed in the following sections. Assessments of significant threat should be made by specialists who have professional knowledge of the behavior of insect and disease populations and other factors that are likely to be affected by blowdown events or ice storms, such increased threat of wildland fire.

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