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Chartered Institution of Water and
Environmental Management (CIWEM)

106-109 Saffron Hill, London, EC1N 8QS  
Tel: 020 7831 3110   Fax: 020 7405 4967

Health Impact Assessment for Land Use Planning


This Policy Position Statement promotes the preparation of appropriate guidelines for Health Impact Assessment (HIA) for major new developments to assist decision making in the planning system. CIWEM supports science-based decision making to protect the environment and human health.

CIWEM believes that:

1. Heath Impact Assessment (HIA) can add value to decision making in the land use planning process.

2. Whilst guidelines for HIA have been developed1 and they may be appropriate for development plans at regional and local levels, for major individual planning applications a formal approach is needed.

3. New guidelines need to be drawn up for a range of land development projects, in consultation with a range of professional bodies, that will be acceptable to developers, consultants, local planning authorities, Primary Care Trusts (PCTs) and the Health Protection Agency. These should draw on the general guidance on HIA issued to date, such as that produced by the Liverpool Public Health Observatory's HIA programme.

4. HIA should not become a statutory requirement for any planning application at this point in time, but should be undertaken on a voluntary basis (with the agreement of the developer, the local planning authority and PCT) until new guidelines acceptable to all key stakeholders are agreed.

5. Given the mandatory nature of Environmental Impact Assessment for major developments, and the voluntary nature of HIA, they should generally be treated as stand-alone reports and not form part of the Environmental Statement.  As improved guidelines are developed and agreed, it might be appropriate to fully integrate HIA into EIA.

6. There should be co-operation in the early stages of significant planning applications between the local planning authority, PCT (and, if relevant, the licensing authority) and developer to ensure that any HIA is appropriate in scope and scale to the proposed development.

7. There is official guidance on the preparation of Health Statements for Integrated Pollution Prevention and Control (IPPC) Permit applications.  Practical experience should inform future reviews of the guidance. Generally, local Pollution Prevention and Control (PPC) applications do not require Health Statements.  An impact assessment is required but stops at a comparison with National Air Quality Objectives and Environmental Assessment Levels (EALs).  By way of comparison, in France, full human health risk assessments for all Permitted activities are required.


The planning system aims to regulate the development and use of land in the public interest, promoting a sustainable pattern of land use that will contribute to meeting the country's economic, social and environmental needs, whilst recognising the precautionary principle. Use of land, under the new planning regime introduced with the Planning and Compulsory Purchase Act 2004, will be set out in Regional Spatial Strategies and Local Development Documents, jointly known as 'development plans'.  Local planning authorities decide upon planning applications according to the development plan, unless there are other key considerations.

The Government is promoting a new planning regime as being a more strategic, proactive force for economic, social and environmental well-being.  At the same time health professionals have come to realise that a wide range of factors in addition to simply the provision of health services are important for determining public health. These include employment, education, housing and the environment. This has led to the development of health impact assessments (HIAs) of policies, plans and projects.

Planning Policy Statement 23 Planning and Pollution Control (PPS23), published in November 2004, states that any potential health impact arising from a development is capable of being a material planning consideration. It goes on to state that the precautionary principle should be invoked where there is good reason to believe that harmful effects may occur to human health and where the level of scientific uncertainty is such that best available scientific advice cannot assess the risk with sufficient confidence to inform decision-making. Furthermore, it advises that the 'objective perception of unacceptable risk to the health or safety of the public arising from the development' needs to be taken into account in the decision-making process.

Large planning applications are generally required to be accompanied by Environmental Impact Assessments (EIAs) documented in Environmental Statements (ESs), which often play an important role in influencing the decision to grant or refuse planning consent for proposed developments.  Although ESs, or the general application documentation, can include assessments of health impacts, they rarely cover the wider social and psychological elements or even the direct impacts in a systematic manner.  In general, environmental benchmarks such as the health protection-based National Air Quality Objectives (NAQO), are used to assess the significance of the potential impacts.  However, there is little discussion of the health impacts of achieving or not achieving the benchmarks.

Health Impact Assessments (HIA) are designed to check whether a proposal might reinforce health inequalities, or inadvertently damage people's health in its widest sense.   Over the past five years there has been growing use of HIA and organisations including the World Health Organisation, the Health Protection Agency, the Welsh Assembly, the London Health Commission and Primary Care Trusts have been promoting their use and have begun to develop good practice guides drawing on the experience of Environmental Impact Assessment.  At the same time, the Department of Health has ensured that local Primary Care Trusts are statutory consultees on any new local Pollution PPC permit applications.

HIA should provide a systematic approach for assessing the potential impacts of proposed policies, plans and projects on the social, psychological and physical health of communities.  It is a tool to appraise both positive (e.g. creation of new jobs) and negative (e.g. generation of pollution) impacts on the different affected subgroups of the population that might result from the proposal being implemented.  Public participation is considered a major component of the process.

In the UK, over 120 HIAs have already been undertaken, largely for the assessment of new policies by the public sector.  One of the problems with the current guidance (although some might see it as its strength) is that it covers such a wide range of applications.  However, the type and scope of issues covered in a HIA for a policy proposal will be very different to those covered for a specific physical development.

There are three types of HIA:

  • Prospective (prior to implementation)
  • Concurrent (during implementation)
  • Retrospective (after implementation).

Of most relevance to the planning system are prospective HIAs, because they can influence a planning decision.  Once a development has planning consent, it is too late to undertake a meaningful HIA, as the consent will not be revoked.

Key Issues

1. The planning process requires health issues to be taken into account, but no systematic approach exists
At present, the planning system is unable to cope adequately with difficult public health issues.  The consequence has been the evolution of somewhat contradictory case law.  For example, a High Court decision regarding a proposed chemical waste treatment plant in Wales concluded that perceived fears of the public, even though they were not based upon scientific fact, were a relevant planning consideration.  Another High Court decision, this time for an expansion of a landfill site in Cornwall, concluded that given the tentative nature of any health effects the council were correct in assuming that the risks, small as they were, could be adequately addressed by the Environment Agency as the regulator of the Waste Management Licence. There is no evidence that the new planning system will be better equipped to deal with such issues.

2. There is a requirement for training and better understanding of the planning system, developers' needs and the science-based approach of EIA amongst HIA professionals
HIA is currently a young and immature activity, largely practised at present by people with little or no knowledge of land use planning and still less of the needs of developers.  Largely, the HIA community is rooted in the public sector and academia, an almost opposite situation to EIA where practitioners are largely in the private sector.  This has produced a set of methods and approaches which are often ill suited to development proposals.

3. There is a difference in approach between HIA (largely qualitative) and EIA (largely quantitative) that must be reconciled before the two may be integrated
The majority of HIA practitioners believe strongly in the community consultation process and place the views expressed through such means above all other evidence.  A 'quantitative' v 'qualitative' schism runs through the HIA community at present, with few in the former camp.  The two things are, of course, complementary, but the majority feel uncomfortable with science-based approaches, which are commonplace in EIA and are the cornerstone of the planning system, and are confirmed in PPS 23.

4. Health concerns are more widely recognised
The new planning regime requires greater public consultation than previously, and therefore local health concerns are likely to figure more prominently in the planning process.

5. Guidance is required on appropriate methodologies and criteria for HIA under IPPC
HIAs have sometimes been required for pollution permit applications for industrial processes.  Since planning consent is not always required for the developments involved (they may fall within an existing planning consent), this forms a separate category of HIA.  Guidance does exist specifically for this application; however, similar issues to HIA for planning applications have arisen.  All cases of industrial HIAs to date involve a specific local health impact of great concern to the local population - although not necessarily significant in terms of a technical risk assessment.  The introduction of IPPC requires formal consideration of health impacts, although still only based on comparison with the NAQOs and EALs for an assessment of potential impact.  The development of appropriate methodologies and criteria is still at a very early stage and is key for all involved.


Developers, particularly of those projects large enough to have a potential impact on community health, have to meet increasing demands for contributions to, for example, the local highway infrastructure, social provisions such as GP surgeries, schools and public open space, and affordable/key worker housing.  The cost of obtaining planning permission can run to several million pounds while the cost of providing the desired facilities can run, if it is a large project, to tens of millions or more.

Currently, there is no statutory requirement for developers to undertake an HIA.  However, local planning authorities are beginning to request them for significant developments within their local authority boundaries.  There may be a perception that developers have ample budgets for incorporating new assessments into their proposals.  The reality is that every land development project has a point at which it is no longer commercially viable and developers are unlikely to agree to undertake an HIA unless it is requested by law, or clearly adds value to the planning process. Either way, what is required must be clearly defined at the outset.

As there is no legal driver for HIA, the fundamental question is 'why should the developer commssion one?'

One of the benefits of HIA to developers is that it is able to demonstrate positive effects for the community, as well as negative impacts.   EIA tends to highlight the negative aspects.  Thus, the major incentive for developers is the possibility that HIA can be used to promote the proposal.

Producing guidelines in co-operation with other professional groups, e.g. town planners, developers and Primary Care Trusts will encourage the use of HIA where appropriate.  In particular, it will reduce developers' fear of the unknown and set boundaries on their commitment.  It will assist in addressing perceived health issues unsupported by mainstream medical evidence with the local community prior to the application being submitted.

Provided appropriate guidance is developed and accepted by the range of professional bodies involved, developers are likely to see benefits in commissioning HIAs.

In summary, HIAs are being undertaken but this kind of assessment is currently an immature activity and the approach used is often incompatible with the land use planning regime's requirement for science-based evidence.  Therefore, the following issues need to be addressed to ensure that HIA has a useful role to play in planning decisions:

  • There is an urgent need to develop appropriate HIA guidelines for the land use planning process
  • There is a need for consultation between the professional bodies involved and other stakeholders when developing the guidelines
  • There should be co-operation in the early stages of land development projects between the local planning authority, PCT, licensing authority (where relevant), and developer to ensure that the HIA is appropriate and adequate in scope and scale to development proposals
  • The related issue of guidance for heath statements for IPPC permit applications needs to be kept under review to ensure that these also add value to the process.  The benefits of the more formal approach to health impacts adopted in France, for example, should be assessed against the costs of adopting such an approach.


1. See Health Impact Assessment Gateway,

December 2005

Note: CIWEM Policy Position Statements (PPS) represents the Institution's views on issues at a particular point in time.  It is accepted that situations change as research provides new evidence.  It should be understood, therefore, that CIWEM PPS's are under constant review, that previously held views may alter and lead to revised PPS's.


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Chartered Institution of Water and
Environmental Management (CIWEM)

106-109 Saffron Hill, London, EC1N 8QS  
Tel: 020 7831 3110   Fax: 020 7405 4967