Surface water management planning: guidance (2018)

Guidance to assist the responsible authorities in preparation of Surface Water Management Plans (SWMPs) to help with the management of surface water flooding.

Appendix 7 Further guidance on assessing wider environmental, social and economic impacts

A7.1 Introduction

This appendix provides further guidance and references to sources of information on assessing the wider environmental, social and economic impacts of surface water management actions. It does not cover every impact, but focuses on those that are most likely to be significant for surface water management planning.

The following sources provide information on the range of impacts resulting from surface water management actions:

A7.2 Human health and wellbeing

Surface water management actions that integrate with and enhance the urban landscape can provide more attractive and inviting places for people.

Good design is essential to ensure that surface water management infrastructure realises multiple benefits and integrates and enhances the urban landscape. It is therefore important that multidisciplinary team that include landscape architects, as well as flood management and drainage engineers, are used.

Good design can bring about significant benefits for human health and wellbeing and improve quality of life. Maximising the use of plants (which also attracts wildlife) together with good landscape design can not only reduce the risk of flooding but provides more attractive and inviting places for people. Connecting to wider ‘green and blue networks’ such as footpaths and cycle paths can improve health and wellbeing by encouraging people to become more active. Improving the quality of the air and water in urban watercourses is also beneficial.

An additional aspect to be considered is whether the option enhances the urban landscape in deprived neighbourhoods, e.g. the lowest deciles of the Scottish Government’s Scottish Index of Multiple Deprivation (see SEPA’s regional pluvial flood risk data has information on social vulnerability to flooding, further information on which can be found in the accompanying guidance on using the data given to responsible authorities. Scottish Government has also mapped flood disadvantage in Scotland (see

Further information on the health impacts of green space can be found in: Health Scotland, greenspace Scotland, Scottish Natural Heritage and the Institute of Occupational Medicine (2008) Health Impact Assessment of greenspace: a guide:

A7.3 Economy

Surface water management actions that integrate with and enhance the urban landscape can attract businesses and investment to an area.

Where local authorities and Scottish Water have co-ordinated work to reduce surface water in the sewer network, capacity in both the sewer network and the water environment, if water quality is also improved, can be expanded to cope with further growth. This could encourage sustainable economic growth in areas where development might otherwise be limited by sewer or environmental capacity. Actions may also help to bring about other economic benefits, such as reducing the costs of water pumping and treatment. (Contact Scottish Water for further information on sewer network capacity.)

A7.4 Water Quality

Surface water management actions that treat surface water run-off and restore urban watercourses can have significant beneficial impacts on river morphology and water quality, thereby helping to achieve the objectives of River Basin Management Plans (see Impacts should be considered both at the location of the option and further down the flow path, and where relevant should include estuarine and coastal impacts.

When assessing impacts on RBMP objectives, the following points should be considered:

  • Will the impact significantly extend the length/area of good (or better) status waters and / or will cumulative impacts of smaller-scale actions contribute to improvements in the water environment? Without detailed modelling impacts will be difficult to quantify, so in many situations a description of the likely direction and magnitude of change will be sufficient.
  • Will the impact help to prevent deterioration of the water environment?
  • Is the affected part of the water environment in a deprived neighbourhood? Impacts in the most deprived neighbourhoods in Scotland should as a rule be considered more significant than similar impacts in less deprived neighbourhoods.
  • How long is the impact expected to last? As a rule, longer term impacts should be considered more significant than shorter terms impacts of similar scale (e.g. SEPA regulatory guidance). [24]

Where local authorities and Scottish Water have co-ordinated work to reduce surface water in the sewer network, the impact on CSO spills should be taken into account. Reducing CSO spills may improve (or prevent deterioration of) water quality in rivers and transitional or coastal waters, as well as bathing water quality at designated beaches. Describing the likely magnitude and direction of change in qualitative terms will be sufficient in the majority of cases. Detailed modelling, in consultation with Scottish Water, would be needed to quantify the change.

A7.5 Biodiversity, habitats and species

Surface water management actions that maximise the use of plants can help to increase wildlife and enhance habitats, to the benefit of species and biodiversity. Habitat connectivity and ecosystem health also stand to gain. A description of the impacts, including magnitude and direction, is likely to be sufficient.

Note that there are specific legal requirements for the protection of habitats and species, which should be considered early in the appraisal process.

SNH has published a wide range of information and data on biodiversity, species and habitats, and habitat networks: Local Biodiversity Actions Plans will also contain information on local biodiversity priorities:

A7.6 Climate change mitigation

The Climate Change (Scotland) Act 2009 set targets to reduce Scotland's greenhouse gas emissions by at least 42% by 2020 and by 80% by 2050, from its 1990/1995 baseline. Public bodies must act in the way best calculated to contribute to the targets.

As a minimum, appraisers should describe whether or not the option is likely to lead to a net increase or decrease in greenhouse gas emissions. This could be through, for example, energy used for maintenance or pumping, or changes to land use and carbon sequestration. This qualitative approach is likely to suffice for most situations.

For large-scale works and more detailed studies, the SWMP partnership may deem it appropriate to quantify impacts on greenhouse gas emissions. The following document provides further guidance on how to do this:


Gordon Robertson:

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