Green Infrastructure, Flooding & Water Management

Green Infrastructure

Green infrastructure (GI) is a multi-functional network of green and blue spaces, urban and rural, that is capable of delivering a wide range of environmental and quality of life benefits for local communities. South Hampshire benefits from a strategic GI network that includes rivers, country parks, the coast, large tracts of woodland and an extensive public rights of way network. Local GI includes smaller scale features such as parks, play areas, allotments, street trees and a network of landscape features such as hedgerows. The GI network also includes recreational routes and green corridors that allow communities to access nature and wildlife to thrive.

Maximising the potential of green infrastructure across South Hampshire is a critical environmental priority for PfSH. High quality GI will help make communities more resilient to the effects of climate change. Enhancing the sub-region’s GI network will be essential in delivering sustainable development that supports the economic aspirations of the sub-region, whilst at the same time enhancing the area’s valued natural environment. Access to GI is proven to contribute to the health and well-being of local communities. High quality GI is as crucial to the delivery of sustainable development as transport, energy, waste and water infrastructure.

PfSH has developed a GI Strategy and associated GI Implementation Plan that together provide an ambitious long-term framework for GI and set out the strategic GI projects that will support and enable growth and development within the sub-region, whilst at the same time deliver a range of environmental and community benefits. PfSH recognise the importance of delivering GI at a ‘landscape-scale’ transcending administrative boundaries and as such the Strategy and Implementation Plan focus on strategic scale GI whilst supporting the delivery of smaller scale GI at the local level.

PfSH are working in partnership with many organisations and individuals to deliver GI improvements and recent successes include significant improvements in the development of strategic country park facilities at: Alver Valley Country Park, Gosport; Horsea Island Country Park, Portsmouth; Manor Farm Country Park, Hamble; and Royal Victoria Country Park, Netley; and to the rights of way network across South Hampshire.

It is important that the GI work of PfSH is integrated with and compliments the GI planning work of others, such as PfSH local planning authorities, catchment partnerships and adjacent administrations. As such, PfSH maintain a ‘live’ list of current GI-relevant strategies and plans within and surrounding South Hampshire.

The South Hampshire GI Strategy and Implementation Plan, together with a list of other GI strategies and plans are available below.


South Hampshire Green Infrastructure Strategy 2017-2034

South Hampshire Green Infrastructure Implementation Plan June 2019

PfSH Table of Relevant Green Infrastructure Strategies and Plans (August 2019)


Flood Risk Management

PfSH Level 1 Strategic Flood Risk Assessment (SFRA) 2024

The PfSH Level 1 Strategic Flood Risk Assessment (SFRA) 2024 update has delivered revised reporting, mapping and guidance notes to replace the document “Partnership for Urban South Hampshire Strategic Flood Risk Assessment 2016.

AECOM was commissioned by Portsmouth City Council on behalf of ten planning
authorities in South Hampshire (the ‘Partnership for South Hampshire’ (PfSH)) to prepare an updated Strategic Flood Risk Assessment (SFRA). The PfSH SFRA covers the administrative areas of Portsmouth City, Havant Borough, Gosport Borough, Fareham Borough, Eastleigh Borough, Southampton City, Winchester City, Test Valley Borough, New Forest District and New Forest National Park Authority.

An SFRA is a study carried out to assess the risk to an area from all sources of flooding, now and in the future, taking into account the impacts of climate change, as well as assessing the cumulative impact that land use changes and development in the area will have on the flood risk. It identifies opportunities to reduce the causes and impacts of flooding and gathers information on the land that is likely to be needed for flood risk management infrastructure. It also informs policies for change of use and reducing the causes and impacts of flooding.

The PfSH SFRA has been prepared in line with the requirements of the National Planning Policy Framework (NPPF), supporting Planning Practice Guidance (PPG) and Environment Agency guidance ‘How to prepare a Strategic Flood Risk Assessment’.

The Environment Agency encourage planning authorities to work together to prepare SFRAs,
particularly where LPAs share a river catchment or coastal area, or where the causes of flooding and solutions to address flood risk lie across LPA boundaries. For the PfSH, there are a number of benefits for collaborating between the LPAs and New Forest NPA to update the SFRA:

  • The planning authorities of Portsmouth City, Havant Borough, Gosport Borough, Fareham
    Borough, Eastleigh Borough, Southampton City, New Forest District and New Forest NPA share the Solent coastline and the shared challenges of coastal erosion and/or tidal flooding
  • There are a number of river catchments that cross planning authority boundaries, including the Test, Itchen, Hamble, Monks Brook, Meon and Wallington River. Collaboration between the planning authorities enables the risk from these watercourses to be considered with a catchment approach
  • The planning authorities are part of the Partnership for South Hampshire and have an
    established track record of collaborative working across the region on housing and green environment work elements.

The objectives of the SFRA were as follows:

  • Assess all potential sources of flooding based on readily available datasets
  • Update existing coastal and river models with new climate change allowances where required
  • Assess the risk of tidal flooding for defended and undefended scenarios, to understand the risk in the future should the level of protection afforded by defences not be maintained
  • Identify existing flood risk management measures as well as areas that need to be adapted to climate change, and areas that need to be safeguarded for future flood risk management features and structures
  • Consider the potential cumulative impact of development and land use change on the risk of flooding in the study area
  • Identify opportunities to reduce the causes and impacts of flooding
  • Provide recommendations for the sustainability appraisal in the preparation of the Local Plan
  • Provide recommendations for the emergency planning capabilities in relation to flood risk
  • Provide guidance for applying the sequential test in the preparation of Local Plans
  • Provide recommendations of how to address flood risk in development, including flood risk from sources other than rivers and the sea.

You can access and download the PfSH Level 1 SFRA 2024 reporting and guidance notes below.

PfSH Strategic Flood Risk Assessment 2024 Part 1 (Main Report)

SFRA Part 1 Appendix A (River Floodplain Analysis)

SFRA Part 1 Appendix B1 East Solent Technical Note

SFRA Part 1 Appendix B2 Southampton Water Technical Note


Part 8 Eastleigh Borough Council

Fareham Borough Council (awaiting publication)

Part 6 Gosport Borough Council

Havant Borough Council (awaiting publication)

New Forest District Council (awaiting publication)

New Forest National Park Authority (awaiting publication)

Portsmouth City Council (awaiting publication)

Southampton City Council (awaiting publication)

Part 2 Test Valley District Council

Part 3 Winchester City Council


Water Management: supply and waste water disposal

PfSH, working with the Environment Agency, Southern Water and Portsmouth Water, completed an Integrated Water Management Study (2008) into the requirements for water supply, water quality, drainage and disposal of waste water, and for designated conservation sites, on a sub-regional basis. Together with other work done by the Agency and the water companies this will guide investment in water related infrastructure over the next 25 years, including addressing existing inadequacies in such infrastructure such as severe capacity constraints in drainage and surface run-off infrastructure. A pilot project will be undertaken in Portsmouth to test ways of separating foul drainage and surface runoff infrastructure to increase capacity.

Further information

Portsmouth Water Water Resources Management Plan (2014)

Southern Water Water Resources Management Plan (2013)