There are many definitions of strategic environmental assessment (SEA). Sadler and Verheem (1996) call it:
"a systematic process for evaluating the environmental consequences of proposed policy, plan or programme initiatives in order to ensure they are fully included and appropriately addressed at the earliest appropriate stage of decision making on par with economic and social considerations."
Therivel et al. (1992) define it as:
"the formalised, systematic and comprehensive process of evaluating the environmental effects of a policy, plan or programme and its alternatives, including the preparation of a written report on the findings of that evaluation, and using the findings in publicly accountable decision-making."
Perhaps the simplest definition of SEA is that it is the environmental impact assessment process applied to policies, plans and programmes, keeping in mind that the process of evaluating environmental impacts at a strategic level is not necessarily the same as evaluating them at a project level.
SEA is meant to be a continuous source of environmental information throughout all the stages of decision-making, as shown below. Note that the stages do not necessarily follows one another: for instance, the identification of alternatives may show that other aspects of the environmental baseline need to be analysed.
|Plan-making stage||SEA stage||Purpose of SEA stage||Adapted from ODPM (2005) A Practical Guide to the Strategic Environmental Assessment Directive, London|
|Early in the plan-making process||Decide whether SEA is needed: "screening"||
|| Context setting
Describe the environmental and policy context that affects the plan: Identify other relevant plans, programmes and environmental protection objectives; Collect baseline information; and Identify environmental problem.
|Establish how the plan is affected by outside factors; provide an evidence base for impact prediction and monitoring; help focus the SEA and streamlining subsequent stages; suggest ideas for how any constraints can be addressed; and help to develop the SEA framework.|
||Develop an SEA framework of objectives and/or indicators||Provide a means by which the environmental performance of the plan and alternatives can be assessed.|
about the scope of the SEA
|Ensure that the SEA covers the likely significant environmental effects of the plan.|
|As the plan evolves||Assessment and mitigation
Plan objectives: Test the plan objectives against the SEA framework; suggest mitigation
|Identify potential synergies or inconsistencies between the plan objectives and SEA objectives; and help in developing plan alternatives.|
||Plan alternatives: Inform the development of plan alternatives, and test the plan alternatives against the SEA framework; suggest mitigation||Develop and refine plan alternatives; predict the significant environmental effects of the plan alternatives; and help in choosing the preferred option.|
||Draft plan: Test the draft plan (preferred option) against the SEA framework; suggest mitigation||Predict the significant environmental effects of the draft plan; and help to fine-tune the plan.|
Preparing the SEA report, including proposing monitoring measures;
|Present the predicted environmental effects of the plan, including alternatives.|
||Consult the public, consultation bodies and others on the draft plan and SEA report||Give the public and others an opportunity to express their opinions on the findings of the SEA Report and use it as a reference point in commenting on the plan; and Gather more information through the opinions and concerns of the public and others.|
||Assess any significant changes made to the plan as a result of plan examination||Ensure that the environmental implications of any significant changes to the draft plan are assessed and taken into account.|
|After plan adoption|| Documentation and monitoring
Provide information on decisions
|Provide information on how the SEA Report and consultees' opinions were taken into account in deciding the final form of the plan|
||Develop aims and methods for monitoring||Track the environmental effects of the plan to show whether they are as predicted; and help to identify adverse effects.|
As a very minimum, the SEA process involves:
- predicting the environmental impacts of a strategic action; and
- using those predictions in decision-making.
If those two basic criteria are not fulfilled, it is not an SEA.
Several other terms are also used to refer to environmental assessment at the strategic level, including:
- policy environmental assessment;
- policy impact assessment;
- sectoral environmental assessment; and
- programmatic environmental impact statement.
The term SEA report refers to a report that describes the methods and findings of the SEA process. Preparation of an SEA report is part of most SEA processes.
What is the aim of SEA?
The main aim of SEA is to incorporate environmental/sustainability issues in strategic decision-making. Secondary aims of SEA are to:
- improve the strategic action by making it clearer, more internally consistent etc;
- involve the public or its representatives in the decision-making process; and
- educate decision-makers about the environmental impacts of their decisions.