CBBIA-IAIA Guidance Document

Impact assessment is carried out to enable us to ‘look before we leap’ into development. Its purpose is both to influence the policy-making and/or planning process, and to inform decision making on development proposals.

Its purpose is to anticipate and prevent, minimize and/or manage, potentially significant negative impacts of development that may:

§ Pose risks to lives, livelihoods or health of current and future generations; and

§ Result in irreplaceable loss of resources and reduced options for future wellbeing.

It also helps to seek opportunities to optimize potential benefits of development.

Impact assessment is either done voluntarily, or in response to legal requirements.

Biodiversity and ecosystem services play a critical role in supporting sustainable development. If impact assessment is to achieve its purpose, it is essential that biodiversity and ecosystem services are taken into account during the impact assessment process. Both the science and society’s values regarding biodiversity and ecosystem services need to be addressed: applicable laws, policies, plans and strategies for biodiversity must be considered, relevant scientific information needs to be gathered and considered, and stakeholders need to be involved and their values incorporated.

This ‘biodiversity-inclusive’ impact assessment should be applied to projects through Environmental Impact Assessment (EIA) and to policies, plans and programmes through Strategic Environmental Assessment (SEA). The CBD Voluntary Guidelines on Biodiversity-Inclusive Impact Assessment (2006) reflect this position[47].

Impact assessment and decision making are influenced by international conventions, SADC (and other regional) protocols, and the regulatory framework of a country or geographic area within that country. Both are informed by information gathered during the impact assessment process, both scientific information and local or traditional or indigenous knowledge (Figure B-1).

Broadly speaking, society’s values at different scales are reflected in conventions, protocols and other regulatory frameworks. As the value systems of society change in response to new information and evolving cultures, they will – over time - influence these frameworks.

It is of the utmost importance that impact assessment, through the evaluation of the significance of impacts, draws both on science and value systems; stakeholder participation plays a key role in finding out the values of an affected society. Similarly, decision makers, in satisfying regulatory requirements, must draw on both science and values; by ensuring that stakeholder participation during the impact assessment has been adequate, and by good co-operative governance with other affected departments, ministries or governments.

Humans, with their cultural diversity, are an integral part of ecosystems. For this reason, our activities can affect different components of our ecosystems, and those ecosystems in turn can have a variety of effects on human activities and associated wellbeing.

Human activities can be direct drivers of change to biodiversity and ecosystem services, either by causing changes in the natural environment, or as a result of social and micro-economic changes that are known to affect the natural environment (Activity 1 in Figure B-2)[48]. Impacts common to specific sectors are highlighted in Part F of this guidance document.

In addition, human activities can be indirect drivers of change through changes in social, cultural and economic policies or practices (Activity 2 in Figure B-2).

Of particular importance with regard to human activities impacting on biodiversity are the following points:

§ Conversion of natural habitat is the main cause of loss of biodiversity world-wide.

§ Alien organisms, once introduced, can invade local ecosystems, ousting the indigenous plants and/or animals and changing these ecosystems. Invasion of natural or semi-natural habitat by alien organisms is the second biggest culprit responsible for loss of biodiversity and degradation of ecosystems.

§ The fragmentation of natural habitat interferes with ecological processes at a landscape scale, isolates living communities, and can lead both to loss of biodiversity and a reduction in the viability of ecosystems in the long term.

EXAMPLE: DIRECT DRIVERS OF CHANGE

o Agriculture, mining, commercial forestry, housing and infrastructure development invariably results in clearing of natural vegetation, changes in drainage patterns, and destruction of habitat for wildlife. The clearing of vegetation could in itself destabilise soils, change local water balances, encourage the spread of alien organisms, or result in the loss of pollinators that are important for local crop production.

o Industrial development often results in water pollution that affects a range of organisms and ecosystems, and may change the quality or quantity of available drinking water.

o Damming or extraction of surface water within a catchment can drastically reduce the water available to downstream users and ecosystems. The reduced water flows can in turn result in changes in water quality, and changes in the structure, composition and processes in fresh water ecosystems.

o Pumping of groundwater can lead to a drop in the water table, in turn leading to drying up of boreholes and wetlands and, when close to the coast, intrusion of salt water into the fresh water aquifer.

o Development in remote areas may open up previously inaccessible natural resources to people, introducing an entirely new set of demands on the affected ecosystems.

o Development may place constraints on the type of ecological processes that can occur in an area, thus affecting the long-term structure and composition of affected ecosystems. For example, large mammals play a key role in determining the structure and composition of savanna ecosystems and their exclusion would have a major effect. Similarly, fire is essential to maintain fynbos ecosystems; where development excludes fire, those ecosystems will not be maintained.

Any or all of these effects could lead to a reduction in livelihood security or quality of life.

EXAMPLE: INDIRECT DRIVERS OF CHANGE

o Collapse of national or local economies and/or the breakdown of infrastructure and services can force people to ‘mine’ ecosystem goods and services (e.g. deforestation, overfishing, etc.) as a last resort to ensure their survival.

o The spread of HIV/AIDS has a number of consequences, not least amongst these being an increase in the number of people who leave formal employment and rely increasingly on subsistence agriculture or fisheries for their livelihoods. The resulting shift in demand on ecosystem goods and services can result in a suite of effects on biodiversity.

o Changes in trade agreements between countries can lead to incentives to switch crops or increase production of certain goods; these changes in turn will lead to different pressures on biodiversity and ecosystem services.

B.2.2 How can natural processes impact on development and human wellbeing?

Different ecosystems provide a range of different opportunities for, and constraints to, development. In order for development to be sustainable, we need to respect, and live within the boundaries set by, these opportunities and constraints. Stated another way, we need to ‘design with nature’. Highly mobile and dynamic ecosystems pose a particular challenge to development: shifting dunefields, floodplains, and the changing position of a river mouth are but some examples of these systems.

In some cases, natural processes can have a major impact on human wellbeing: floods, erosion of coastlines, outbreaks of disease, landslides and dust-storms are a few examples. In many instances, human interference with ecological processes has increased the severity of their impact.

THE CONSEQUENCES OF INTERFERING WITH ECOLOGICAL PROCESSES

EXAMPLE: HURRICANE KATRINA, NEW ORLEANS[49]

Background: The city of New Orleans in the state of Louisiana, USA, was built on marshland in the floodplain of the Mississippi River. The first part of the city was built on natural river levées along the river. Then, drainage of the formerly marshy ground allowed the city to expand. However, this drainage resulted in subsidence, making those areas more prone to periodic flooding. Indeed, since 1878 the city has sunk by 4.6m, meaning that nearly 80% of New Orleans lies below sea level—more than 2.5m below in places. The main causes of subsidence were pumping of groundwater, dewatering of marshland, soil compaction, building levées on the Mississippi River and reducing sediment supplies to coastal areas. Furthermore, significant areas of Louisiana’s coastal wetlands have been reclaimed or developed for oil and gas exploration and production activities, thus reducing their ability to act as sponges and flood regulators. In addition to man-made perturbations, Louisiana is losing its protective fringe of marshes and barrier islands faster than any place in the U.S.A: since the 1930s some 4,900 square kilometres of coastal wetlands have vanished beneath the Gulf of Mexico. Despite nearly half a billion dollars spent over the past decade to stem the tide, the state continues to lose about 65 square kilometres each year, making the coast and its inhabitants particularly vulnerable to storm surges and extreme weather conditions.

Consequences: Against this background, it is hardly surprising that when Hurricane Katrina hit the city on the 29 August 2005, about 80% of the city of New Orleans was flooded, with some parts of the city under 6m of water. Over 1,100 deaths were recorded. The flood was called "the largest civil engineering disaster in the history of the United States”. Although the magnitude and intensity of Hurricane Katrina would have undoubtedly wreaked havoc along the coastline even under pristine conditions, the severity of the impacts would not have been so devastating if human beings had not interfered with the natural coastal protective systems and built in such a dynamic environment as a river delta.

EXAMPLE: INTERFERING IN COASTAL SYSTEMSIN SOUTH AFRICA

Along many parts of the South African coast, large areas of coastal sand dunes have been stabilized for residential or other infrastructure development. The stabilization of these dunes has effectively starved downstream ecosystems of their sand supply – the sand that would normally move along the coast and maintain wide sandy beaches popular with visitors and tourists, has been ‘tied up’ in the dunes. In some areas, e.g. Cape St Francis in the Eastern Cape, consideration is being given to establishing artificial reefs to ‘nourish’ the beaches with sand, at considerable cost.

In other coastal areas, development has been allowed within the mobile dune systems, often with disastrous consequences: in Still Bay, on the south coast of South Africa, holiday houses have been buried in moving sand; some coastal roads are continually being inundated with moving sand.

Estuaries are amongst our most productive ecosystems. Development within the flood plains and/or on wetlands associated with these ecosystems has led to flooding in some instances, and reduction in the abundance of bait organisms and fisheries in others.

EXAMPLE: INTRODUCTION OF ALIEN INVASIVE ORGANISMS

The introduction of alien organisms into our indigenous systems can have major consequences if these organisms ‘invade’ local systems. They can change the structure, composition and ecological processes in affected ecosystems, and thus the ecosystem services that they provide. In South Africa, around seven percent of mean annual run-off is being lost to invasive alien plants that were introduced largely for commercial forestry purposes but have spread into catchments and drainage lines. These alien plants increase the risks of fire, soil erosion and flooding. These invasions can have a major negative impact on the economy. For example, in the Cape Floristic Region, the costs of lost ecosystem services due to alien invasive plants are estimated at about R700 million per annum (2000 figures). [50]

Similarly, alien water plants such as the water hyacinth can reduce the quality of drinking water, increase flood damage, interfere with water-based transport, clog water pipes, interfere with hydroelectricity generation, and promote water-borne diseases, amongst others.

The following principles should be applied during impact assessment at either strategic or project levels (refer to Part D on Strategic Environmental Assessment, and Part E on Environmental Impact Assessment, for more detailed information). The Voluntary Guidelines on Biodiversity-Inclusive Impact Assessment give valuable information on this and related respects[51].

The ecosystem approach is advocated by the Convention on Biological Diversity. It recognizes that people and biodiversity are part of the broader ecosystems on which they depend, and that they should thus be assessed in an integrated way[52]. The main principles for implementing the Ecosystem Approach are given in Box B-1.

o The objectives of ecosystem management are a matter of societal choice.

o Ecosystem managers should consider the effects of their activities on adjacent and other systems.

o Conservation of ecosystem structure and functioning, to maintain ecosystem services, should be a priority target.

o Ecosystems must be managed within the limits of their functioning.

o The approach must be undertaken at appropriate spatial and temporal scales.

o Objectives for ecosystem management should be set for the long-term.

o Management must recognise that change is inevitable.

o The approach should seek an appropriate balance between, and integration of, conservation and use of biodiversity.

o All forms of relevant information should be considered.

o All relevant sectors of society and scientific disciplines should be involved.

B.3.2 Apply ‘positive planning’, looking at opportunities and constraints

Ideally, biodiversity pattern and process, and ecosystem services, should be considered proactively at the earliest possible stage of planning, be it at strategic or project level (Box B-2). The more advanced the planning, the less flexibility there is for considering alternatives that would best meet sustainable development objectives. In other words, one should strive to plan and ‘design with nature’[53]. The opposite of ‘positive planning’ is shown in Figure B-3 below[54].

Good planning and impact assessment should clearly identify and select those alternatives that offer the greatest overall benefits and avoid undesirable impacts for the good of society. Decision making, too, should strive to this end. That is, the evaluation of alternatives is an essential part of impact assessment and decision making.

Where reasonable alternatives are not considered in impact assessment and decision making, these decisions are invariably flawed and open to challenge by stakeholders, leading to delays and costs. Where there is thorough consideration of alternatives, stakeholder buy-in is achieved and an optimum proposal emerges. Two examples, both involving the development of a golf course and residential estate, are given below to illustrate these points.

EXAMPLE: POOR CONSIDERATION OF ALTERNATIVES, SOUTH AFRICA

Proposed development: A golf course with residential and tourism components, on the banks of a major river and next to a nature reserve and conservancy. The site of development contained sensitive components, in that it is classified as a ‘biodiversity hotspot’ by the provincial environmental authority. It lies partly within the Cradle of Humankind World Heritage Site, and contains a number of Red Data Book species of birds, mammals, invertebrates and flora.

Potential significance of impacts on biodiversity: All of the specialists involved in the EIA identified negative impacts with a ‘very high’ and ‘high’ significance. They stated that these ratings could be reduced if the site layout were changed to protect the areas of high ecological sensitivity. No changes were made. The draft scoping report concluded that impacts would be ‘low’ in spite of the fact that the site layout was not altered at all.

The impact assessment: The environmental authority stated early on in the planning process that the EIA would have to clearly address, amongst other issues, the need and desirability of the development, loss of habitat, loss of migration corridors, open space connectivity, impacts on fauna and flora, with particular attention to Red Data species. The authority requested a sensitivity map which would show the sensitive areas in relation to the layout of the proposed development.

The decision: The authority approved the development, in spite of the fact that many of its own requirements were not met by the EIA. The Record of Decision was appealed on the basis of, amongst others, lack of consideration of alternatives, inconsistency with government policy, and inadequate information on biodiversity, but the appeal was rejected and the decision upheld.

Key lesson/s: Poor consideration of alternatives led to appeals on the decision and development delays.

EXAMPLE: GOOD CONSIDERATION OF ALTERNATIVES, SOUTH AFRICA

Proposed development and potential significance of impacts on biodiversity: A golf course, with residential and commercial/tourism components. The site of development contained sensitive components, namely a seasonal wetland and seepage area, and an area of Critically Endangered indigenous vegetation within the global biodiversity hotspot of the Cape Floristic Region.

The impact assessment: Five alternatives were considered, informed by input from the environmental authority, local authorities, the biodiversity agency, agriculture and water authorities, and key non-government organizations. The final scale, layout and design of the proposed development responded fully to the opportunities and constraints of the natural environment.

The decision: The authority approved the development. Stakeholders responded positively to the outcome of the impact assessment.

Key lesson/s: Good consideration of alternatives at the outset, and throughout the process, resulted in a positive outcome for the proponent and stakeholders.

Sustainable use of biodiversity means that harvests of renewable natural resources can be maintained over time. That is, the rate of harvesting (or fishing or culling) is either the same as, or less than, the rate of replenishment or regeneration of that resource.

Sustainable use of ecosystem services means that essential life-support systems can be maintained over time. That is, the biodiversity underpinning the ecosystem service is safeguarded to ensure that both the quality and quantity of that service does not deteriorate.

The sustainable use of biodiversity and ecosystem services is essential for securing sustainable livelihoods. The example of the introduction of the Nile perch into Lake Victoria (Section A.5.2) highlights the unsustainable use of an ecosystem and its biodiversity.

There is a hierarchy of possible mitigation that can be used to avoid or reduce negative impacts (Box B-3). The emphasis in this hierarchy is on avoiding or preventing impacts, and/or reducing or minimizing them – the positive planning approach (described in B.3.2) is important here.

o Avoiding or preventing the impact through the early consideration of opportunities and constraints and development alternatives (positive planning) and by modifying the proposal accordingly;

o Reducing or minimizing negative impacts and maximising benefits, by considering alternatives and modifying the proposal;

o Rectifying negative impacts by restoring the affected environment to its previous condition, or rehabilitating it for a different land use; and

o As a ‘last resort’, providing an offset to compensate for the residual negative impact on biodiversity or ecosystem services, by replacing or providing ‘like for like or better’ substitutes for these impacts. In cases where residual impacts affect threatened, unique or irreplaceable biodiversity, offsets are not an option as substitutes do not exist.

Unfortunately, it seems that both consultants and decision makers in the SADC region often ignore this hierarchy.

Interesting to note: Findings of the Situation Assessment, Southern Africa[56]

o The consideration of biodiversity ‘too late’ in the impact assessment frequently means that mitigation focuses on damage limitation rather than avoiding or preventing the impact.

o Mitigation measures recommended in impact assessments are often no more that ambitious and vague statements of intent, on the basis of which the potential significance of impacts is reduced. In many cases the authorities do not appear to critically evaluate the substance of the proposed mitigation measures, and accept the residual significance ratings without question.

o In some cases, reference was made to offsets as motivation for allowing loss of biodiversity, whilst mitigation options higher up in the mitigation hierarchy had been effectively ignored.

EXAMPLE: INAPPROPRIATE USE OF OFFSETS AS MITIGATION

Proposed development and potential significance of impacts on biodiversity: A film studio plus housing development that would result in the loss of significant urban wetland. The lost wetland potentially plays an important role in flood regulation and water cleansing in the area, and it forms part of a ‘priority’ biodiversity corridor in the city. Its loss could increase downstream flooding, affecting poor and vulnerable downstream communities, and could result in the loss to the city of significant biodiversity.

The impact assessment: Did not consider alternative locations for the proposed development, but looked at development alternatives on the site that would be ‘financially viable’ to the proponent. The socioeconomic benefits of the project were emphasized.

The decision: Development was authorized on condition that a monetary offset was provided to compensate for the loss of wetland habitat.

Key lesson/s: There are no opportunities to re-create the lost wetland within the city, and its loss is thus considered to be irreplaceable in that context. The monetary offset is inappropriate; it would not satisfy the objective of avoiding loss of biodiversity. Alternative locations for the proposed development should have been investigated within the city’s limits.

EXAMPLE: APPROPRIATE USE OF OFFSETS AS MITIGATION

Proposed development and potential significance of impacts on biodiversity: A proposed resort and housing development that would have an unavoidable residual negative impact on Endangered vegetation on the affected property.

The impact assessment and decision: The development would have substantial benefits in terms of uplifting local communities. It was authorized on condition that a trust fund be set up to protect and manage the same Endangered vegetation on three other sites within the municipal area.

Key lesson/s: The type of offset would make a assured and positive contribution to protecting threatened biodiversity and attaining conservation targets for the affected vegetation.

The Precautionary Principle states that “where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation”[57].

Simply stated, if we are not sure what’s going to happen as a result of doing something, and the effects could be severe and irreversible, and could compromise our future, we should avoid taking any risks. Action to avert serious or irreversible environmental damage may be required before scientific certainty of the harm exists, and by the time we have gathered enough evidence to be certain, it may be too late to act[58].

The combination of uncertainty and the risk of irreversible effects or loss of irreplaceable resources summarises the challenge to decision-makers with regard to the sustainable use and development of natural systems[59].

The terms ‘risk’, ‘hazard’, ‘uncertainty’ are defined in Box B-4. Society as a whole, or affected parties in particular, choose the level of risk and/or hazard that they are prepared to accept. Where there is uncertainty and the probabilities of impacts - or their significance - cannot be determined with confidence, and/or the opportunity costs of choosing a particular path could be high, it is wise to apply caution in decision making.

§ Loss of biodiversity is frequently irreplaceable; extinction is forever. Negative impacts on ecosystem services are also often irreplaceable, or replaceable only at great cost.

§ Changes in biodiversity can affect how an ecosystem works. While some of these impacts can be predicted, others can’t. As biodiversity decreases, ecosystem services deteriorate.

§ Climate change is altering the face of our region, and with it, many of the ecosystems and associated services on which we depend.

§ Loss of biodiversity pattern and process undermines the resilience of ecosystems and their ability to evolve and adapt to changing conditions. Our own ability to adapt to such things as climate change would be compromised should we allow loss of biodiversity.

Clearly, the penalties for taking decisions that allow for loss of biodiversity and negative impacts on ecosystem services could be substantial. In addition, they could be contrary to the goal of sustainable development, namely not to compromise the ability of future generations to meet their own needs.

Box B-5 gives guidance on the application of the precautionary principle in practice[61]. When risk and uncertainty levels are both high, it is essential to apply the precautionary principle strictly.

The examples below illustrate the need for a precautionary approach when there are gaps in information and alternatives have not been addressed.

EXAMPLE: GAPS IN INFORMATION, LACK OF PRECAUTION, SOUTH AFRICA

Proposed development: Housing estate within the buffer zone of a UNESCO Biosphere Reserve.

Potential significance of impacts on biodiversity: About 80% of the site constituted a well-established wetland/seepage area of importance to biodiversity, and a main drainage route to a significant wetland system downstream.

The impact assessment: A specialist study as part of the impact assessment focused on vegetation only. This study made a number of recommendations as to the need for more detailed studies on hydrology, threatened plant species, and the role of the site in the broader wetland system, in order to evaluate reliably likely impacts. No such studies were commissioned. The proposed development places housing in areas of ‘high’ to ‘extreme’ sensitivity, that were specifically recommended for exclusion from housing development by the specialist. Two of the three alternatives proposed by the specialist as development options were not addressed. A previous study for the proposed development, undertaken by a geohydrologist/ecologist, was effectively ignored in the impact assessment. This study concluded that the site should not be developed.

The decision: The development was initially approved, but authorization was subsequently denied on appeal.

Key lesson/s: Major gaps in information, disregard of specialist input and recommendations with regard to alternative proposals, as well as disregard for indications that additional specialist studies were necessary to produce a reliable EIA, led to the proposed development being turned down.

EXAMPLE: INADEQUATE CONSIDERATION OF GAPS IN INFORMATION - CASE STUDY FOR HYDROPOWER SCHEME, TANZANIA[62]

Proposed development: The hydropower scheme comprises three hydropower turbines to generate electricity in the Kihansi Gorge, with provision for an additional two turbines in future. Infrastructure comprises a gravity dam (25m high) with a storage volume of 1 million m³ taking up about 26ha, a vertical intake shaft connecting to the headrace tunnel and the underground power house. Most of the water is diverted from the falls in the Gorge, and then channeled back to the river.

Potential significance of impacts on biodiversity: The Kihansi Gorge lies in the Eastern Arc Forests, of global and national importance for biodiversity conservation. The large cloud of spray from the falls in the Gorge creates a unique habitat near the base of the falls; a new species of toad (Kihansi Spray Toad) with an extremely restricted distribution (about 4ha in total) was discovered in late 1996 during planning for long-term environmental monitoring. Several new or endemic species were found in the Gorge, including 4 new species of plant and a range of threatened species. Fish species in the river are significant from a biodiversity perspective. A number of NGOs and the scientific community raised concerns about the potential irreversible loss of biodiversity in the Kihansi Gorge as a result of the project; in particular, the unique toad population was at risk of extinction through a 95-99% loss of spray-maintained habitat.

The impact assessment: Not legally required, but carried out to meet donor funding requirements. The original impact assessment (1990) was largely a desk study and failed to pick up important issues; the limited on-site investigation was based mostly on hear-say evidence from local villagers and omitted any survey of the most environmentally sensitive region (the Kihansi Gorge) downstream of the proposed dams. An additional impact assessment (1991) relied to a large extent on desk studies, interviews of local inhabitants and an extremely limited field survey which dealt only with trees, birds and mammals; no survey was undertaken in Kihansi Gorge itself. A more comprehensive EIA (1994) provided more detailed information and included surveys within the Gorge, but time constraints prevented it from adequately covering the vulnerability of the spray wetland ecosystems in the Gorge.

The decision: No formal decision linked to EIA. Construction of the Lower Kihansi Hydropower Project started in 1994, it was officially opened in July 2000.

Key lesson/s: There was inadequate information to inform the decision on the proposed hydropower project from a biodiversity / ecosystem services perspective. This case study also highlights the importance of addressing alternatives - had probable impacts of the Lower Kihansi Hydropower project within the Kihansi Gorge been identified earlier, the Upper Kihansi Hydropower project (proposed in conjunction with the former) could have been selected for construction first to allow time for detailed studies in the Kihansi Gorge to be carried out prior to further development of the Lower Kihansi project. The Upper scheme would have had far lower impacts on the Kihansi Gorge ecosystems, as the water used for power generation would be returned to the Kihansi River upstream of the Gorge.

The Convention on Biological Diversity and the Ramsar Convention require that development ensures the fair and equitable sharing of benefits arising from the use of biodiversity. In line with sustainable development, the needs of future as well as current generations must be considered, and alternatives must be sought that don’t irreversibly ‘cash in’ biodiversity capital to meet short-term needs.

Where the negative impacts of development lead to an increase in vulnerability of poor people, and/or where society as a whole is left worse off with regard to ecosystem services as a result of development that benefits a few relatively wealthy parties, the condition of equitable sharing is not met.

Equitable sharing also applies to the fair access to natural resources. It has been shown that insecure tenure or access to natural resources discourages sustainable natural resource management[64]. (Please also refer to A.5.4 with regard to social justice and equity.)

In addition to the above points, the following principles should be applied during impact assessment at either strategic or project levels (refer to Parts D and E for more detailed information):

§ Consider the bigger, strategic context withing which the proposal is being evaluated. For example, the global, regional or national policy, planning and/or other strategic framework, specifically with regard to the conservation of biodiversity and ecosystem services.

§ Involving all relevant stakeholders, particularly those authorities responsible for biodiversity conservation, those groups with an interest in biodiversity and those parties who currently use or have access to, directly or indirectly rely on or benefit from, affected ecosystems.

§ Using all available and relevant information, including local, traditional and indigenous knowledge. As well as scientific information, other types of information about, and values of, the affected biodiversity and ecosystem services, must be gathered and used.

§ Defining time and space boundaries of the study. It is essential to ‘set the scene’ and the scope of the SEA or EIA, to ensure that it is sufficient to enable the impacts within and between ecosystems to be addressed, and to allow both long and short term impacts on biodiversity and ecosystem services, both on and beyond the directly affected area, to be considered.

§ Drawing up good Terms of Reference. Good Terms of Reference are essential to ensure that answers to questions about impacts on biodiversity, ecosystem services and associated human wellbeing will be answered in the impact assessment and related specialist studies[65]. Where the Terms of Reference are inappropriate (e.g. focus only a specific site rather than the broader landscape, or on a specific stretch of river excluding downstream impacts), the impact assessment will not be reliable or useful as a planning and decision making tool.

In this Part of the guidance document, you will find the following sections:
B.1	Why do we do impact assessment, and what is meant by ‘biodiversity-inclusive’ impact assessment?
	B.1.1	Why do we do impact assessment?
	B.1.2	What is meant by biodiversity-inclusive impact assessment?
	B.1.3	Science, values, regulatory tools and biodiversity
B.2	How do human activities impact on biodiversity and ecosystem services, and vice versa?
	B.2.1	What can cause impacts on biodiversity and ecosystem services?
	B.2.2	How can natural processes impact on development and human wellbeing?
B.3	Good practice impact assessment, and consideration of biodiversity and ecosystem services
	B.3.1	Use the ecosystem approach
	B.3.2	Apply positive planning, looking at opportunities and constraints
	B.3.3	Always consider alternatives
	B.3.4	Ensure sustainable use
	B.3.5	Use the hierarchy in considering mitigation measures
	B.3.6	Always apply the precautionary principle
	B.3.7	Ensure equitable sharing
	B.3.8	Apply these other common principles in SEA and EIA

Box B-5: Applying the precautionary principle The following considerations should be applied:
For a critically endangered or endangered ecosystem or species, a protected ecosystem or species, a previously un-recorded species or species about which little is known, and/or for ecosystems or species that play a significant role in supporting lives or livelihoods, where impacts could be of high significance, irreversible, lead to irreplaceable loss of natural capital, and/or there is little prior experience or scientific confidence about the outcome:	*Follow the strict precautionary principle*. Impacts should be confined within the realm of complete reversibility, and only those activities which have been shown to pose negligible risks to biodiversity should be permitted. Mitigation, including offsets should totally and reliably compensate for impacts on biodiversity to ensure no change in conservation status, providing for a margin of error where there may be uncertainty as to the effectiveness of mitigation.
*For a vulnerable ecosystem and/or species, and/or for ecosystems or species that play a role in supporting lives or livelihoods* where impacts could be long-term and significant:	Only those human-induced activities which pose low risk to biodiversity should be permitted. Impacts should be mitigated in full and, in a ‘worst case’ scenario, residual impacts should be offset to ensure that there would not be a change in status to ‘endangered’. Where there is uncertainty as to the likely effectiveness of mitigation, a margin of error should be provided.
*For an ecosystem and/or species* which is *currently not threatened and/or not known to play a role in supporting lives or livelihoods*:	Human-induced activities which pose some risk to biodiversity should be permitted. However, impacts must be mitigated and offset as far as practicable.