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Weaving Ecosystem Services into Impact Assessment

A Step-by-Step Method

This report introduces the Ecosystem Services Review for Impact Assessment (ESR for IA), a six step method to address project impacts and dependencies on ecosystem services as part of the environmental and social impact assessment process. The steps build on assessments routinely conducted by social and environmental practitioners to better reflect the interdependence between project, ecosystems, ecosystem services, and people.

Practitioners seeking more detailed guidance on implementing the ESR for IA can consult the associated Technical Appendix, which will walk them through each step and sub-step using an illustrative case study.


Download Technical Appendix (Version 1.0)

Executive Summary

The services provided by ecosystems play a vital role in human well-being. Although some ecosystem services are easily recognized— food, timber, and freshwater, for example— others may be less apparent. Ecosystems control erosion; reduce the damage caused by natural disasters; and regulate our air, water, and soil quality. A reduction or loss of any of these services and the benefits they provide can have socio-economic ramifications that reverberate beyond environmental damages.

Standard environmental and social impact assessments (ESIAs) do not specifically account for a project’s impacts on ecosystem service benefits. As a result, assessments might overlook stakeholders who are vulnerable to ecosystem change, or miss some of the harmful social consequences of a project’s environmental effects. Integrating ecosystem services into impact assessments results in a more comprehensive and realistic assessment of a project’s immediate and long-term impacts.

Responding to the need to identify and plan for these impacts, ESIA standards have started to integrate ecosystem services into project impact assessments. The International Finance Corporation’s (IFC) performance standards reflect this trend: as of 2012, IFC-financed projects are required to preserve the benefits from ecosystem services. Going a step beyond project impacts, the IFC also requires that the environmental and social risks and impacts identification process considers a project’s dependence on ecosystem services. Just as development projects can jeopardize the benefits that flow from ecosystem services, changes in ecosystems can endanger project outcomes.

Until now, there has been little guidance for ESIA practitioners on how to integrate ecosystem services into their impact assessments. The World Resources Institute, in collaboration with ESIA practitioners, developed the “Ecosystem Services Review for Impact Assessment” (ESR for IA) to fill this gap. The ESR for IA is a structured methodology that guides practitioners through six steps to incorporate ecosystem services into ESIA at the scoping, baseline and impact analysis, and mitigation stages.

The ESR for IA can be used for two purposes. First, it identifies measures to mitigate project impacts on the benefits provided by ecosystems. Second, it identifies measures to manage operational dependencies on ecosystems. These goals are reflected in the ESR for IA’s four outputs:

  • A list of ecosystem services, for inclusion in the ESIA terms of reference;

  • Identification of priority ecosystem services to be considered and stakeholders to be engaged in further stages of the ESIA process, for inclusion in the ESIA report;

  • Assessment of project impacts and dependencies on priority ecosystem services, for inclusion in the ESIA report; and

  • Measures to mitigate project impacts and manage project dependencies on priority ecosystem services, for inclusion in the environmental and social management plans.

The ESR for IA, rather than replacing the environmental and social assessments that make up the standard ESIA process, complements them with an interdisciplinary, integrated framework. By focusing attention on the socio-economic dimensions of a project’s environmental impacts, the ESR for IA can capture the unanticipated costs and benefits of projects more fully than a standard ESIA, and can identify stakeholders who might otherwise be missed.

WRI and ESIA practitioners road-tested the ESR for IA by applying the methodology to projects that had already undergone standard environmental and social assessments. The results were promising. The ESR for IA revealed overlooked social implications of environmental impacts, exposed operational risks resulting from ecosystem change, and identified additional measures for the environmental and social management plans.

Weaving Ecosystem Services Into Impact Assessment: A Step-by-Step Method is an abbreviated version of a longer WRI report that provides detailed, technical instructions for ESIA practitioners. This condensed version is tailored to a broader audience, including project developers who do not conduct ESIAs themselves, but nevertheless need to understand the process. We encourage project developers and ESIA practitioners to share their experiences using the ESR for IA with others, for example, through LinkedIn’s Business & Ecosystem Services Professionals and Environmental Impact Assessment groups. The lessons learned from their implementation can inform the emerging community of practice around ecosystem services in ESIA and contribute to refinements in the methodology down the road.

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