1. General information
Location and description of the intervention
City or FUA
Portsmouth
Region
Europe
Short description of the intervention
Milton Common is the second stage of the multi-million-pound Flooding and Coastal Erosion Risk Management scheme being developed across the north of Portsea Island, from Mountbatten Centre round to Milton Common. The overall project will reduce the risk of coastal flooding and erosion and provide the critical infrastructure the city will need over the next 100 years (6).
As the second phase, Milton Common included the instalment of a new rock revetment as a plans defence, the creation of a coastal path and three new earth bunds with new footpaths (6). The work has also included the demolition of Great Salterns Quay and restoration of the natural mudflat habitat (2,4).
The fully completed scheme will significantly reduce the risk of coastal flooding to Milton Common and the local area over the next 100 years; it will offer protection against a 1 in 500-year flood event providing one of the highest standards of flood protection in the UK outside of London (6).
Address

Sywell Cres
Portsmouth
PO3 5UB
United Kingdom

Location
The NBS is a city-wide initiative, the GIS point marks the centre of the city
Type of area before implementation of the NBS
Natural Heritage Area/Untouched nature
Website of the intervention
https://www.portsmouth.gov.uk/ext/environment/coastal-defence-management.aspx
Timeline of intervention
Start date of the intervention (planning process)
2014
Start date of intervention (implementation process)
2015
End date of the intervention
2024
Present stage of the intervention
Ongoing
Please specify "other" stage of the intervention
The introduced second stage: Milton Common has been realised by 2016, however, the Flooding and Coastal Erosion Risk Management scheme is ongoing until 2024 based on the project timeline (7)
Goals of the intervention
1. Deliver a combined, efficient and comprehensive coastal management service (1)
2. Reduce the risk of coastal flooding and erosion, as well as the developed and natural environment. (1)
3. Post-construction, the area to be enhanced through an extensive replanting programme - increase the diversity of plants in the area, improving the current ecosystems and habitats for wildlife. (5)
4. Construct 1.5km of setback earth embankments and rock revetment structure (1)
Quantitative targets
- The scheme will offer protection against a 1 in 500 year coastal flood event. (5)
- reduce the risk of coastal flooding and erosion to over 4,700 homes and businesses (4)
Monitoring indicators defined
1. 1.5 kilometers of coastline covered (5)
2. Number of homes/businesses protected from the risk of coastal flooding and erosion (ref 4)
Sustainability challenge(s) addressed
Climate action for adaptation, resilience and mitigation (SDG 13)
Climate change adaptation
Water management (SDG 6)
Flood protection
Coastal resilience and marine protection (SDG 14)
Coastal protection / hazard mitigation
Green space, habitats and biodiversity (SDG 15)
Green space creation and/or management
Climate change adaptation: What were the goals of the NBS?
Reduce the impacts of climate risks events on urban places and communities
Build resilience
Climate change adaptation: What activities are implemented to realize the conservation goals and targets?
Protect coastal and freshwater ecosystems to prevent coastal erosion and pollution
Restore wetlands and/or coastal ecosystems to dissipate the effects of flooding and/or storms
Implementation activities
- Installation of a new rock revetment, constructed from granite Larvikite delivered from Norway (6)
- Creation of a coastal path and three new earth bunds with new footpaths (6)
- Demolition of the old Great Salterns Quay, so the area can return to its natural mudflat habitat. (4,6)
- Installation of a new section sea wall to provide a continued level of defence along the coastline, following the removal of the quay (6)
- Landscaping of both the Milton and Anchorage Park sites has started with native trees, shrubs, grasses and wildflowers being planted.(3)
Type of NBS project
Coastal landscape management or protection
NBS domain and interventions
Ecological domain(s) where the NBS intervention(s) is/are implemented
Blue infrastructure
Coastlines
Please specify "other parks or (semi)natural urban green area"
old Great Salterns Quay has been removed so the area can return to its natural mudflat habitat (3)
Vegetation Type
Grass
Shrubs
Trees
Other
Please specify how many trees were planted
Unknown
Amenities offered by the NBS
Benches and drinking water stations
Services
Expected ecosystem services delivered
Regulating services
Coastal protection
Flood regulation
Habitat and supporting services
Habitats for species
Cultural services
Aesthetic appreciation
Recreation
Scale
Spatial scale
Meso-scale: Regional, metropolitan and urban level
Beneficiaries
Primary Beneficiaries
Local government/Municipality
Citizens or community groups
Governance
Governance arrangements
Government-led
Please specify the roles of the specific government and non-government actor groups involved in the initiative
Eastern Solent Coastal Partnership (ESCP) (now called Coastal Partnership) is delivering the project on behalf of Portsmouth City Council. (1)
Key actors - initiating organization
Regional government
Local government/municipality
Land owners
Public space owned by the city
Key actors - Other stakeholders involved (besides initiating actors)
Regional government
Local government/municipality
Land owners
Public space owned by the city
Participatory methods/forms of community involvement used
Unknown
Policy drivers
NBS intervention implemented in response to an Regional Directive/Strategy
Unknown
NBS intervention implemented in response to a national regulations/strategy/plan
Yes
Please specify the national regulations/strategy/plan
Coastal Flood and Erosion Risk Management (CFERM) Scheme (1): Milton Common is the second phase of construction of new coastal defense designed as part of the North Portsea Island Coastal Flood and Erosion Risk Management (CFERM) Scheme (5)
NBS intervention implemented in response to a local regulation/strategy/plan
Yes
Please specify the "local regulation/strategy/plan"
North Solent SMP- Shoreline Management Plan (SMP) (5)
Mandatory or voluntary intervention
Mandatory (based on policy)
Intervention is mandatory
Spatial planning law
Enablers
Presence of specific city-level GI/NBS vision/strategy/plan - mentioned in connection to the project
Yes
Please specify
Portsea Island Coastal Strategy (5) The strategy looked at the likely risk of coastal flooding to Portsea Island, the condition of existing defense and the number of properties and assets at risk in the event of flooding over the next 100 years. (5)
Presence of specific city-level GI/NBS section/part in a more general plan - mentioned in connection to the project
Unknown
If there is a relevant strategy or plan, please specify the theme / type of the plan.
City specific green space strategy or plan
Please specify other vegetation type
mudflat habitat, wild flowers
Presence of city network or regional partnerships focused on NBS - mentioned in connection to the project
Yes
Please specify
The project leader organisation, Coastal Partners (formerly called Eastern Solent Coastal Partnership) is a partnership between four councils who manage 162km of Hampshire’s coastline (9)
Presence of GI / NBS research project - mentioned in connection to the project
Unknown
Subsidies/investment for GI / NBS in the city - mentioned in connection to the project
Unknown
Co-finance for NBS
Unknown
Co-financing governance arrangements
Yes
Co-governance arrangement
Other
Please specify other co-financing type
Partnership
Was this co-governance arrangement already in place, or was it set up specifically for this NBS?
Already in place
Financing
Total cost
More than €4,000,000
What is/was the Cost/Budget (EUR) of the NBS or green infrastructure elements?
£3 million (approximately 3.1 million EUR)
What are the total amount of expected annual maintenance costs?
Unknown
What is the expected annual maintenance costs of the NBS or GI elements?
Unknown
Please specify cost savings
Unknown
Please specify total cost (EUR)
The coastal defense measures at Milton Common is the second phase of a multi-million pound Flooding and Coastal Erosion Risk Management scheme. The total costs of the Milton Common phase was £3 million (apporximately 3.1 million EUR) (7)
Source(s) of funding
Public local authority budget
Type of fund(s) used
Earmarked public budget
Non-financial contribution
Unknown
Business models
Risk reduction model
Which of the involved actors was motivated by this model?
Public actor (e.g. municipality)
Type of innovation
Technological
Infrastructural innovation
Please specify technological innovation
New paths along most of the coastline and the area will be replanted with specially selected trees, shrubs, meadow grasses and coastal wildflowers. Great Salterns Quay will be removed as part of the scheme and returned to its natural mudflat habitat. (ref 4)
Novelty level of the innovation
Unknown
Please specify novelty level of the innovation
Unknown
Replicability/Transferability
Unknown
Please specify Replicability/Transferability
Unknown
Impacts, benefits
Environmental impacts
Climate change
Increased protection against sea level rise
Strengthened capacity to address climate hazards/natural disasters
Water management and blue areas
Increased protection against flooding
Enhanced protection and restoration of coastal and marine ecosystems
Green space and habitat
Promotion of naturalistic styles of landscape design for urban development
Increased green space area
Increased conservation or restoration of ecosystems
Increased number of species present
Description of environmental benefits
- The fully completed scheme will significantly reduce the risk of coastal flooding to Milton Common and the local area over the next 100 years; it will offer protection against a 1 in 500-year flood event providing one of the highest standards of flood protection in the UK outside of London. (6)
- With the demolition of the Great Salterns Quay, the area can return to its natural mudflat habitat, thus increasing the green space in the area (2,4)
- As part of the landscape design, wildflower mix, grass, and native trees have been planed in the area including Hawthorn, Sea Buckthorn, Crab apple, Field Maple, Thrift, Sea Purslane, Sea Campion, and several species of wildflower including Poppies, Bird’s Foot Trefoil, Corn Marigold and Yarrow (6)
- Once completed, the whole project will reduce the risk of flooding and erosion from the sea to 4,200 homes, 500 businesses and critical infrastructure including the Eastern Road over the next 100 years (6)
Economic impacts
Unknown
Description of economic benefits
Unknown
Social and cultural impacts
Health and wellbeing
Gain in activities for recreation and exercise
Description of social and cultural benefits
- The old benches at Milton Common have been refurbished and will be replaced to provide recreational facilities in the area (6)
- With the creation of a coastal path and three new earth bunds with new footpaths, visitors have new opportunities for recreation and physical activity (6)
Type of reported impacts
Expected impacts
Achieved impacts
Indicators
Unknown
Environmental, social and economic impacts
Coastal resilience and marine protection (SDG 14)
Green space, habitats and biodiversity (SDG 15)
Analysis of specific impact categories
Job creation: The NBS created ...
No information available
Negative impacts: Did the project cause any problems or concerns?
No information was found regarding negative impacts of the project
COVID-19 pandemic
Unknown as of November 2020
Methods of impact monitoring
Process of recording NBS impacts
No evidence in public records
Methods used to evaluate the impacts of NBS
Unknown
Evidence for use of assessment
Presence of an assessment, evaluation and/or monitoring process
Unknown
Presence of indicators used in reporting
No evidence in public records
Presence of monitoring/evaluation reports
No evidence in public records
Availability of a web-based monitoring tool
No evidence in public records
Impact assessment mechanism
Name of any specific impact assessment tools
Unknown
Use of GIS in mapping impacts
No evidence in public records
Citizen involvement
Citizens involvement in assessment/evaluation
Unknown
Citizens involvement in the analysis of the assessment/evaluation
Unknown
Follow-up to the evaluation / assessment
Unknown
References
Web links relevant to the intervention
Eastern Solent Coastal Partnership
List of references
1. Eastern Solent Coastal Partnership. (n.d). Coastal Schemes -Portsmouth - Anchorage Park. Website not available
2. The Portsmouth News. (2016). Work continues on revamp of Portsmouth’s flood defences. Accessed on Nvember 12, 2020, http://www.portsmouth.co.uk/news/politics/work-continues-on-revamp-of-portsmouth-s-flood-defences-1-7321232
3. The Portsmouth News. (2016). Next phase of Portsmouth coastal defence improvement work to begin in 2017. Accessed on November 12, 2020, http://www.portsmouth.co.uk/business/next-phase-of-portsmouth-coastal-defence-improvement-work-to-begin-in-2017-1-7669474
4. AboutMyArea News. (2016). Milton Phase of Coastal Defence Work Begins Next Week. Accessed on November 12, 2020, http://www.aboutmyarea.co.uk/Hampshire/Portsmouth/PO6/News/Local-News/298327-Milton-Phase-of-Coastal-Defence-Work-Begins-Next-Week
5. Portsmouth City Council. (n.d). New Coastal Defences Protecting the Future of Anchorage Park.Website not available
6. Coastal Partners. (n.d). North Portsea Island - Milton Common, Phase 2. Accessed on November 12, 2020, https://coastalpartners.org.uk/project/north-portsea-island-milton-common-9/
7. Coastal Partners. (n.d). Protecting the Future of North Portsea Island. Accessed on November 12, 2020, https://coastalpartners.org.uk/project/protecting-the-future-of-north-portsea-island/
8. Coastal Partners. (n.d). North Portsea Island - Anchorage Park, Phase 1. Accessed on November 12, 2020, https://coastalpartners.org.uk/project/north-portsea-island-anchorage-park-8-8/
Comments and notes
Public Images
North Portsea Island - Milton Common
Source: https://coastalpartners.org.uk/project/north-portsea-island-milton-common-9/
North Portsea Island - Milton Common
Source: https://coastalpartners.org.uk/project/north-portsea-island-milton-common-9/
North Portsea Island - Milton Common
Source: https://coastalpartners.org.uk/project/north-portsea-island-milton-common-9/
North Portsea Island - Milton Common
Source: https://coastalpartners.org.uk/project/north-portsea-island-milton-common-9/