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.

2 The surface water management planning process

2.1 Principles of surface water management planning

The aim of a surface water management plan is to reduce the risk of surface water flooding in the most sustainable way, as required under the FRM Act.

Range of sustainable actions
SWMPs are likely to include a range of different actions. These should be the most sustainable combination of actions necessary to manage the risk of surface water flooding (see Appendix 4 for a list of potential actions). The most sustainable actions are those that are the most economically, socially and environmentally advantageous.

SWMPs may also include actions that are the responsibility of different authorities. In such cases, the SWMPS will help to co-ordinate funding and implementation across the relevant authorities. Funding may come from various sources, depending on the cost of implementation and the authority responsible.

Long-term, iterative approach
SWMPs should set out a long-term vision for sustainably managing surface water flooding in an area and the actions needed to achieve that vision. More detailed information is likely to be available for priority actions that will be implemented in the shorter term while less information may be available for longer term actions.

The process should be iterative. SWMPs should be monitored, reviewed and updated with timescales for reviews and updates that take into account the six-year Flood Risk Management Planning cycle. The benefits of adopting a longer term, iterative approach include the ability to:

  • Include new data, thereby ensuring that the plan is based on the best available information.
  • Monitor how effective actions are that have been implemented and trial innovative solutions.
  • Plan for new actions to achieve the long-term vision.
  • Adapt to changing circumstances.
  • Tackle problems in stages. Surface water flooding is often widespread and fragmented across an urban area so that in many cases it is not feasible to solve all surface water flooding problems at once.
  • Co-ordinate with other projects and authorities to realise multiple benefits. It allows different authorities to identify where and when there may be opportunities for co-ordination or joint working. This is more difficult when authorities are focused on their own priorities over the short-term.
  • Be more cost-effective. Some surface water management actions may only become cost-effective if implemented alongside other projects. Long-term planning helps to identify where and when this can be done.

Surface water management plans should be risk-based in order that effort and investment can be directed toward areas at greatest risk of flooding and where the most benefits can be achieved.

SWMPs can be carried out at any geographical scale, focusing more detail on areas at greatest risk. For example, an SWMP could be carried out for an entire local authority ( LA) area but should contain more detail on locations within it that have been designated by FRM Strategies as being at higher risk (and any other areas of interest to the local authority). Or, a larger urban area could be covered by many SWMPs.

All stages of the surface water management planning process should be informed by risk. The level of detail to go into at each stage (e.g. number of outputs and detail provided for each output) will depend on a number of factors, including: the level of flood risk; the complexity of the flooding problem; the availability of resources; and, the availability of, and confidence in, existing data.

2.2 Stages of the surface water management planning process

Figure 2.1 and Table 2.1 show the stages to be followed when developing and implementing a surface water management plan. All stages are consistent with the development of the FRM Strategy and the principles of the FRM Act.

Figure 2.1 Stages of the surface water management planning process

Figure 2.1 Stages of the surface water management planning process

Table 2.1 Summary of surface water management planning stages

SWMP stage Summary Example outputs
  • Resources.
  • Governance.
  • Consultation and co-ordination.
  • Collating existing information on surface water flooding.
  • Validating existing information.
  • Scoping level of detail and defining geographical scale of the SWMP(s).
  • Initial findings of key stakeholder consultation.
  • Data on flood hazard and risk.
  • Data register.
  • Section of SWMP report clearly communicating findings of this stage.
  • Other outputs, e.g. GIS (geographic information systems) data and maps showing key information (e.g. SWMP areas).
Understand flood risk
  • Analysing and interpreting information to understand surface water flood hazard and risk.
  • Identifying areas with greatest risk.
  • Consultation and co-ordination.
  • Section of SWMP report clearly communicating the sources, pathways and adverse impacts (risk) of surface water flooding.
  • Identification of areas with greatest risk.
  • Other outputs, e.g. GIS data and maps showing key information (e.g. flood hazard and risk, areas with greatest risk), communication material for different audiences.
Set objectives
  • Confirming objectives from FRM Strategies
  • Setting more detailed objectives for areas with greatest risk.
  • Prioritising objectives if required.
  • Key consultation and co-ordination stage to identify other projects that could be carried out jointly to aid delivery and realise multiple benefits.
  • Consultation findings.
  • Section of SWMP report clearly communicating objectives, indicators and priority of objectives.
  • Other outputs, e.g. GIS data and maps showing key information (e.g. areas of greatest risk, objectives for these areas and their priority), communication material for different audiences.
Option appraisal
  • Scoping the option appraisal, confirming objectives (e.g. high-level appraisal for all objectives or more detailed appraisal and design for priority objectives).
  • Developing and comparing options for each objective in order to choose preferred option.
  • Consultation and co-ordination
  • Understanding the degree of confidence in the appraisal.
  • Section of SWMP report clearly communicating the outcomes of this stage, including reasons for selecting preferred option.
  • Co-ordination and joint working where required to develop options that will yield multiple benefits.
  • Other outputs, e.g. supporting information for the option appraisal, clear communication of information to aid decision making, consultation material for different audiences.
Develop preferred option, confirm funding
  • Developing preferred option in more detail.
  • Confirming responsibilities and funding.
  • Section of SWMP report clearly communicating the outcomes of this stage, including confirmed action plan and SMART objectives.
Finalise and communicate plan
  • Producing an SWMP report that summarises key findings and outputs, and includes proposals for monitoring, implementing, reviewing and updating the plan.
  • Considering communication material for other stakeholders and the public.
  • Detailed SWMP report that provides sufficient information to guide those implementing the plan.
  • Summary report and maps, including action plan to communicate clearly with other stakeholders, e.g. the public.
  • Data pack to help share key information, e.g. key GIS outputs, maps, action plan.
Implement and monitor actions
  • Implementing actions.
  • Monitoring success of the actions to determine progress towards achieving objectives.
  • Gathering information on complete actions.
  • Updated summaries of all actions and their status (e.g. a ‘live implementation plan’) to aid co-ordination and communication, including confirming when an action is complete and objectives achieved.
  • Key information about complete actions recorded and shared with stakeholders.
Review and update SWMP
  • The SWMP is a long-term process that should follow the flood risk management planning cycles.
  • When reviewing and updating SWMPs the development stages should be repeated and any required changes made, provide information on complete and planned actions.
  • Updated or new outputs, e.g. SWMP report; summary SWMP for clear communication to other stakeholders; technical reports; updated ‘data pack’ to help share key information with others and aid co-ordination, e.g. key GIS outputs, maps, action plan (showing information on complete and planned actions).

2.3 SWMP timescales and flood risk management planning

The flood risk management planning process runs on a six-year cycle, the statutory dates for which are shown in Figure 2.2. Key tasks and dates to consider for surface water management planning are:

  • SEPA update of pluvial hazard and risk data – the data should be used to inform (or may trigger) a review and update of surface water management plans. At the time of publication SEPA had no timescale for the next update but it will share the information with responsible authorities when it becomes available.
  • More detailed modelling of pluvial flood hazard and risk by LAs – if a local authority has more detailed modelling of pluvial flood hazard and risk it should contact SEPA to determine whether SEPA’s pluvial flood hazard and risk maps should be updated. As the FRM planning process is cyclical, data can be provided to SEPA at any time. That said, key flood risk management planning dates should be considered to allow new data to be included in any National Flood Risk Assessments ( NFRAs) or FRM Strategies: for example, SEPA would need data prior to the publication of an NFRA for it to be incorporated – e.g. by 2018 for FRM Strategy 2, or by 2022 for NFRA 3 (as part of FRMP 3 development).
  • Review and update of SWMP areas 2019, 2025 etc. – SEPA, in consultation with LAs and Scottish Water, will lead on reviewing and updating SWMP areas before each six-yearly FRM Strategy public consultation. LAs should therefore share any knowledge of surface water flooding in their area (e.g. based on observed flood events or more detailed modelling) with SEPA. New SWMP areas may be included if information shows there is a greater risk of surface water flooding than was previously identified; conversely existing SWMP areas may be removed where new information shows the risk to be lower.
  • Actions (planned and completed) identified through the SWMP 2019, 2025 etc. – in order to inform the FRM Strategy’s prioritisation process and funding decisions, LAs should submit information on any planned actions identified through the SWMP process as requiring prioritisation, before each six-yearly public consultation (i.e. 2019, 2025 etc.). Information on completed actions should be provided for progress to be reported. Any actions relevant to the SWMP and confirmed by other authorities (e.g. Scottish Water) can also be included in time for the FRM Strategy public consultation stage, even if they do not require FRM Strategy prioritisation for funding decisions.
Figure 2.2 Key dates for FRMP and SWMP

Figure 2.2 Key dates for FRMP and SWMP


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