Review the Coastal Commission Memorandum: Mitigation for Natural Resource Impacts - Background for Caltrans Projects (April 2022)

To further understand the Commission’s guidance and interpretation of ESHA restrictions, view the webcast of, or slides from, the ESHA workshop held at the April 2016 Commission hearing.

ESHA Basics

ESHA designations are usually based on the presence of plants, animals, or habitat types that have been designated as "rare" by the California Department of Fish and Wildlife or other competent authority. ESHAs may also include areas that are especially valuable because of their special nature, such as supporting a species’ population with unusual genetic characteristics, or important ecosystem functions, like providing a critical wildlife movement corridor.

The Coastal Act restricts development within ESHAs to only those uses that are dependent on the resource, and requires that ESHAs be protected against significant disruption of habitat values. It also requires that development in areas adjacent to ESHAs and parks and recreation areas be sited and designed to prevent degradation of those areas and to be compatible with the continuance of those habitat and recreation areas. The required development setback from an ESHA is based on the resource of concern, such as raptor nests or special-status species habitats, and on other considerations, such as the probable type and intensity of disturbance. Setbacks are commonly 100 feet but may be larger—for example, 500 feet or more from some raptor habitats.

Coastal Act Policies Related to ESHA

  • Coastal Act Section 30107.5 labels ESHA as "any area in which plant or animal life or their habitats are either rare or especially valuable because of their special nature or role in an ecosystem and which could be easily disturbed or degraded by human activities and developments."

  • Coastal Act Section 30121 identifies wetlands, which often qualify as ESHA, as "lands within the coastal zone which may be covered periodically or permanently with shallow water and include saltwater marshes, freshwater marshes, open or closed brackish water marshes, swamps, mudflats, and fens."

    Under the Coastal Commission’s definition of wetlands (see California Code of Regulations Section 13577(b)), a wetland need only display one of the parameters typically used to define wetland areas, in contrast to the U.S. Army Corps of Engineers, which uses a three-parameter definition under its federal authorities. The diking, filling or dredging of wetlands is generally permitted for specific purposes listed in Coastal Act Section 30233, regardless of whether the wetland also meets the definition of ESHA.

  • Coastal Act Section 30240 states:
    • Environmentally sensitive habitat areas shall be protected against any significant disruption of habitat values, and only uses dependent on those resources shall be allowed within those areas.
    • Development in areas adjacent to environmentally sensitive habitat areas and parks and recreation areas shall be sited and designed to prevent impacts which would significantly degrade those areas, and shall be compatible with the continuance of those habitat and recreation areas.

ESHA considerations when developing your project and preparing to submit a coastal development permit

When applying for a CDP from the Commission or a local agency, it is critical to accurately identify, map, and assess the underlying habitat types potentially affected by a project. This is because the Coastal Act and Local Coastal Programs (LCPs) only allow resource-dependent uses within ESHAs to ensure the long-term protection of the habitat. Transportation facilities are not considered resource-dependent uses allowed within ESHAs. Ultimately, it is the responsibility of the Commission or local agency to determine, based on the information provided by the applicant, input from experts from other agencies, and actual conditions on the ground, whether an area qualifies as an ESHA.

To help determine a project’s consistency with applicable ESHA policies and its potential for approval, consider the following:

  • Baseline: When assessing the presence of ESHA, the Commission will often look to historical documentation, such as aerial photography, to establish if disturbed areas adjacent to or within ESHA were cleared or disturbed pursuant to a valid local or Commission CDP. This is different than the baseline used to assess a project’s impacts in an environmental document under the California Environmental Quality Act or the National Environmental Policy Act. Biological reports that are current or less than one year old are also usually required to assess the value, habitat function, and coverage of biological resources present within a project site.

  • Allowable Uses: The Coastal Act and LCPs require that only development dependent on the resource be allowed in an ESHA. The Commission has found that such things as hiking and educational trails, low-impact camping, educational signage and kiosks, research, and restoration qualify as resource-dependent development. However, the use of nonnative, invasive plants in any landscaping plans, or certain operational components such as night lighting, particularly in locations in or adjacent to sensitive areas, are generally prohibited or greatly restricted.

  • Alternatives Analysis: Most Caltrans development does not qualify as an "allowable use" in ESHA; therefore, a thorough alternatives analysis is required to determine if there is a feasible alignment, design, or buffer alternative that would avoid the impact to ESHAs. Even where development impacts are allowed in an ESHA (see “Conflict Resolution,” below), the Commission is required to identify the least environmentally damaging alternative when making findings pertaining to the ESHA.

  • Avoidance and Minimization: If the project is not an allowable use in an ESHA, the use of mitigation measures alone will not ensure the Commission can approve a project. Where development is allowed in an ESHA (see “Conflict Resolution,” below), the analysis of project impacts on the identified ESHA should discuss avoidance and minimization efforts taken to reduce effects and mitigate to the greatest extent feasible.

  • Conflict Resolution: In exceptional circumstances, the Commission may use the Coastal Act’s “conflict resolution” provisions (Sections 30007.5 and 30200(b)) to approve non-resource-dependent uses in an ESHA. In cases where either approval or denial of a project would result in conflicts between Chapter 3 Coastal Act resource protection policies, these provisions allow the Commission to select the course of action that, on balance, is the most protective of significant coastal resources, even if it will cause impacts that are generally prohibited by the Act. In these cases, there must also be no feasible less environmentally damaging alternative, and mitigation measures must be provided to minimize adverse environmental effects.