Prevention

Public Awareness and Preparedness

EXAMPLE: Developing an Attica Wetland Action Plan (GR)

nst — Thu, 16 Feb 2017 08:27:37 +0000

EXAMPLE: Developing an Attica Wetland Action Plan (GR) nst Thu, 02/16/2017 - 09:27

Non-structural measure

Attica, Greece is a region with extensive wetlands that include streams, estuaries and coastal marshes. The land area is also heavily in use for agriculture and experiences competition from various anthropocentric uses which have created a largely degraded environment. The wetlands that dot the region, are largely considered by communities as the remaining environmental hotspots and serve not only as ecologically important areas but peoples’ remaining contact with nature. They are for this reason, closely tied to community use and general well being. To protect these wetlands, an Attica Wetland Action Plan was developed.

Based on the information available on ClimateAdapt Platform

General description

Recognising the need for the sustainable and ecological management of these wetlands the Environmental Department of Attica Regional Authority with support from the Greek Biotope Wetland Centre (EKBY) developed an Attica Wetland Action Plan. The Action Plan is designed around seven axes under which measures with specific priority actions are identified. The strategy includes sustainable management and restoration of wetlands; their interconnection in a green arc; the evaluation of the services provided; awareness raising and environmental education in biodiversity and climate change and citizen participation.

The Action Plan is built on seven axes under which measures are listed and assigned priority. The development of the Action Plan sought to protect and preserve the biodiverse wetlands while simultaneously creating sustainable opportunities for use by the local community. In order to ensure acceptance and eventual implementation of the Action Plan, participation by the affected communities was central to its design and development. While there were no issues in developing the plan, ensuring its effective implementation faced several limiting factors including limited funds, operational capacity of involved services and bodies to take proposed action measure, regulation of land uses in relation to protection and restoration.

The region of Attica is a Metropolitan Region and the first in Greece to be mobilized towards a climate change adaptation strategy. It therefore was new in bringing a participatory process forward to propose management for natural ecosystems while dealing with sensitive issues of competitive land use between agricultural needs and environmental ones. The local authorities development of an Adaptation Plan brought together local authorities, social groups, environmental organisations and research institutes for the protection of wetlands in its jurisdiction.

Cost-effective and innovative aspects

The planned implementation of the Action Plan is meant to mitigate the effects of human interventions resulting from usage (i.e. agriculture) as well as pressures stemming from climate change. Implementing the suggested measures is expected to improve the protection of the coasts by reducing the effects of waves, storms and currents. It is also expected to improve water quality in the region by trapping sediments, nutrients and toxic substances. It is also expected to improve the possibility of economic returns of those using the wetlands.

During the development of the Adaptation Plan several awareness raising events were organized in the wetland in order to involve and educate local community members. For example, in 2014 a training seminar “Adaptation Strategy for Attica Wetlands” provided hands-on training for some 80 participants. In 2015, the Attica Region had a Green Week event called “Raising support to restore the wetland of Brexiza, in the Region of Attica Greece” which brought some 90 individuals to Brexiza to learn about the biodiversity of the area and its historical importance as an archaeological site of the Roman great temple of the Egyptian gods. Through public support, this event brought about a dialogue on Brexiza wetland restoration and biodiversity protection as well as on the implementation of the Action Plan.

Key lessons learnt

Prior to the development of the regional Adaptation Plan, knowledge and awareness about climate change adaptation and wetlands in particular was low and non-existent in the community. The partnership between the Regional Authority and a scientific environmental organisation, was an important partnership for mutual learning and the introduction of climate change planning for the first time. Moreover, the development of the Adptation Plan was participatory in its design, and thus generated wide support for the suggested measures despite previous issues related to competitive land use and widespread environmental degradation. The development of the Adaptation Plan had the effect of raising awareness of citizens and other actors, facilitating new collaborations between private, public and governmental actors, and generally brought into consideration a sustainable management plan for the wetlands.

In regions or situations where adaptation to climate change is being introduced for the first time, ensuring a participatory process whereby actors develop management plans through mutual learning and exchange

Relevant case studies and examples

Spatial Planning and Integrated Coastal Zone Management (ICZM)

Measure category

Land claim

nst — Tue, 07 Feb 2017 13:09:59 +0000

Land claim nst Tue, 02/07/2017 - 14:09

Combined approach (grey + green)

Move seaward

EXAMPLE: Artificial Island - Amager Beach, Copenhagen (DK)

The main objective of land claim is neither erosion nor storm reduction. The aim of land claim is to create new land from areas that were previously below high tide. These measures can be taken to reduce the exposure of these areas to coastal flooding. For example, in Singapore and Hong Kong, there are enforced minimum reclamation levels to account for future sea level rise

Based on information from ClimateTechWiki.

General Description

Land claim is likely to be accomplished by enclosing or filling shore or nearshore areas (Bird, 2005). Several alternative terms may be used when referring to land claim; these may include land reclamation, reclamation fill and advance the line. Typically this measure is undertaken to gain land (French, 1997), today especially around coastal cities (like Singapore and Hong Kong), where very high land values are justifying the costs.

In order to enclose areas for land claim, hard coastal defences must be constructed seaward of the existing shoreline. Dike and seawalls are typically constructed to protect the claimed land from flooding by the sea (Burgess et al., 2007). Two main methods of land claim are: (1) enclosing and defending shore or nearshore areas; and (2) filling shore or nearshore areas, often using the same techniques used in beach nourishment. When considering adaptation to climate change, land claim using fill methods is perhaps more appropriate as it does not carry such a great flood risk.

Advantages and disadvantages of the technology

The key advantage of land claim is the gain of additional coastal land for uses such as agriculture or development. Apart from the valuable land, this additional coastal land can function as a buffer and reducing the risks of flooding.

Land claim can also generate a number of negative impacts. The process of land claim requires either the enclosure of intertidal habitats by hard defences, or the raising of their elevation above that of sea level to prevent inundation. This causes the direct loss of intertidal habitats such as saltmarshes, intertidal flats and sand dunes (French, 1997). Another disadvantage is dewatering. By draining reclaimed land which has a high water content, land is caused to dry out, compact and shrink (French, 1997), thus reducing its elevation in relation to sea level. This causes a difference between land elevations inside the flood defences, where compaction and shrinkage has occurred and outside, where natural intertidal environments continue to naturally accrete sediments. This difference in elevation is also exacerbated by SLR and results in an ever increasing requirement for flood defences (Burgess et al., 2007). It also requires an ongoing commitment to defend these areas (French, 1997).

Any type of land claim will cause the displacement of water during a natural tidal cycle. Because of this displacement, incoming tides have a smaller area to inundate. This will cause water depths to increase and will mean intertidal areas are submerged for longer – this has the potential to cause negative biological consequences and can also increase the tidal range upstream (French, 1997).

Financial requirements and costs

The financial costs of land reclamation are dependent on a number of factors:

Chosen method of reclaim (enclosing previously intertidal areas using hard defences or raising the elevation of previously submerged land)
Availability and proximity of fill material from onshore or offshore sites
Number, type, size and availability of dredgers
Requirement for hard protection measures to defend reclaimed land from coastal flooding and erosion
Project size and resulting economies of scale
Estimated material losses

If land claim is conducted by enclosing previously intertidal areas, the additional costs of providing hard protective measures, such as seawalls or dikes, to prevent flooding and erosion of these areas is important. Ongoing maintenance costs for these structures must also be considered.

If land claim is achieved by raising the elevation of previously submerged land, the cost of fill material is likely to be the main determinant of project cost. In turn, this cost will be influenced by the availability of appropriate materials, their proximity to the construction site and the characteristics of the reclaim site – this influences the type of dredging equipment which can be used. Changes in the cost of fill material are likely to occur in future due to increased demand and greater restrictions on dredging.

Institutional and organisational aspects

The institutional and organisational requirements of land claim projects are likely to depend on the scale and ambition of the project. Small-scale land claim for agricultural uses is more likely to be achievable at the community level than large-scale island enlargement and creation as seen in Singapore or Dubai. These large-scale projects will require the involvement of large organisations and large amounts of funding.

Key lessons learnt

One barrier to the use of land claim is potential long-term costs. Land claim creates land which will require protection from coastal flooding and/or erosion. This requires construction of defences such as seawalls or dikes with associated construction and ongoing maintenance costs. Land claim through elevation raising may also be a cost-effective method of disposing of dredged material from ports, harbours and navigation channels. This could reduce the overall cost and eliminate the need to identify offshore disposal sites for dredge material. As with beach nourishment, pollutant levels in the dredge material should be carefully monitored.

Environmental concerns may provide another barrier to implementation. By reclaiming land in these areas, environmentally important intertidal habitats are lost, and knock-on impacts such as alterations to ebb/flood dominance may also occur. As a result, environmental opposition to land claim may mount. In the EU, compensation for lost habitats is required

Relevant case studies and examples

Further Readings

Wang et al (2014): Development and management of land reclamation in China

Literature sources

Bird, E. (2005) Appendix 5: Glossary of Coastal Geomorphology in Schwartz, M.L. (ed.). Encyclopedia of Coastal Science. The Netherlands: Springer, 1155-1192.

Burgess, K., Jay, H. and Nicholls, R.J. (2007) Drivers of coastal erosion in Thorne, C.R., Evans, E.P. and Penning-Rowsell, E.C. (eds.). Future Flooding and Coastal Erosion Risks. London: Thomas Telford, 267-279.

French, P.W. (1997) Coastal and Estuarine Management. London: Routledge.

Measure category

EXAMPLE: MOSE system of mobile flood barriers, Venice (IT)

nst — Tue, 07 Feb 2017 08:35:19 +0000

EXAMPLE: MOSE system of mobile flood barriers, Venice (IT) nst Tue, 02/07/2017 - 09:35

Flash floods

Reduction

Water flow regulation

Hold the line

Flood and storm surge barrier

Venice, Italy, is a city famous around the world for not only its stunning canals and historic buildings, but also for its high vulnerability to flooding. The MOSE system of mobile flood barriers is a bold initiative intended reduce risk, preserve the cherished cityscape, and protect the entire Venice Lagoon from flooding.

Based on information from the project website

General description

The MOSE (short for “Modulo Sperimentale Elettromeccanico” in Italian) system consists of four mobile barriers closing off three inlets in the Venice Lagoon. The barriers themselves are made up of 78 flap gates that are installed at the bottom of the inlets to separate the lagoon from the sea when raised. The system takes approximately 30 minutes to open and can be closed in 15 minutes, but takes on average five hours to close. Once raised, the barriers are able to withstand three meters of high tide. The barrier at the Malamocco inlet even has a lock system installed to allow merchant and industrial ships to cross while the MOSE system is in operation to reduce interference on port activities.

Seasonal high water is a constant threat to Venice, and the city has adapted with raised walkways, waterproofed buildings, and power outlets installed halfway up the wall in businesses and homes. Flooded scenes of a usually picturesque St Mark’s Square can be explained due to the fact that it is the city’s lowest point. However, more extreme high tides that occur roughly every three years and can raise water levels by over a meter present a much greater risk to Venice’s cultural heritage and justify a system such as MOSE.

Governance aspects

Venice and its Lagoon is a UNESCO World Heritage Site, which makes its protection even more important. The MOSE project was implemented by the Italian Ministry of Infrastructure and Transport and managed by the Consorzio Venezia Nuova for the purposes safeguarding Venice and the lagoon. The decision to construct the mobile flood barriers was made after collaboration between all levels of government and consideration of various other coastal defence measures.

Innovative aspects

The MOSE system in its entirety is an impressive and innovation response to the threat of coastal flooding and erosion, both from a construction and coordination standpoint. The hydrological and geophysical profile of the Venice Lagoon needed to be fully considered when designing the barriers and their final locations.

While the MOSE Control Centre uses advanced technology to predict flooding, model the effects of gate manoeuvres, predict port traffic, determine warning levels, and so on, the MOSE project also employs other smaller scale measures to optimise the overall goal of flood risk reduction in the lagoon. These local defences consist of raising quaysides, roads, walkways, and installing smaller gates in the urban canals in the lagoon settlements, known as the “Baby MOSE” gates. This holistic and comprehensive approach to encouraging protection for the entire lagoon, aside from that which is provided by MOSE, is also innovative.

Key lessons learnt

It is not easy to construct such large-scale defences in fragile environments, but, as the MOSE system illustrates, sometimes this approach is necessary to provide significant long-term protection. Venice represents an especially vulnerable coastal city with globally significant heritage sites and a very active tourism industry. With so much at risk, the MOSE system will ensure businesses, residents, and visitors will be able to enjoy the fabled canals, palaces, and plazas without the threat of flooding and building damage. The implementation of local defences diversifies the resilience of the settlements in the lagoon and increases the rate of success for the MOSE project.

Relevant case studies and examples

Further Readings

CityLab: Venice's Vast New Flood Barrier Is Almost Here

Measure category

Riverine or slow rise floods

EXAMPLE: Lowering the floodplain in Emilia–Romagna area (IT)

nst — Fri, 27 Jan 2017 12:48:53 +0000

EXAMPLE: Lowering the floodplain in Emilia–Romagna area (IT) nst Fri, 01/27/2017 - 13:48

Channel, Coastal and Floodplain Works

Combined approach (grey + green)

Near to the RISC-KIT Case Study in Emilia – Romagna, a LIFE+ “LIFE RINASCE” project has been implemented in 2014 to improve some of Emilia - Romagna drainage channels in the Po floodplain. Project leader is the Emilia Centrale Land Reclamation Consortium, in collaboration with the Emilia -Romagna Region. The project was started in 2014 and will run the end of 2018 with a total budget of almost 2.1 million €.

Based on the project information from LIFE+

General description

The project aim is to reduce the risk of flooding and achieve good ecological status of the waters in the Po floodplain through ecological restoration of the channel network and vegetation management. It aims at demonstrating the feasibility and environmental and socio-economic benefits of such measures on a large floodplain area.

The project plans to develop an integrated restoration programme for floodplain channels using river restoration methods and protocols for sustainable management of aquatic and riparian vegetation. Planned interventions will aim to restore hydraulic functions of the floodplain, reduce the risk of flooding and improve the ecology.

One measure among others will include the lowering of the floodplain and thereby creating an arboreal strip of plants and shrubs. Other measures include the creation of a wetland, the enlargement of a natural channel. These measures are aimed to mitigate flood risks through water retention. Other benefits will be the improvement of drainage, purification of water, and improved ecological status.

It is foreseen that seven kilometer of canals will be restored by the end of the project by the creation and/or the lowering of three hectares of floodplain areas and vegetation. Additionally two hectare wetland should be created by then.

The Participatory process

The project used a participatory process to involve local actors, stakeholders and citizens in the strategic choices regarding the transformation of the territory and to collect ideas and proposals for the design of the rehabilitation interventions. Information, communication, consultation and listening to participants played an important role for the first steps in the project. The process was split into two main plenary sessions, six discussion meetings and a follow-up meeting for the technical and regulatory aspects hosted. These meetings involved a total of 189 participants coming from associations, organizations, companies and citizens. In parallel, the participatory process was supported by a dedicated web space.

Relevant case studies and examples

River bank relocation – floodplain lowering

Further Readings

Website of the project (in Italian)

Measure category

EXAMPLE: Relocation of Clavell Tower, Dorset (UK)

nst — Thu, 26 Jan 2017 15:00:34 +0000

EXAMPLE: Relocation of Clavell Tower, Dorset (UK) nst Thu, 01/26/2017 - 16:00

Combined approach (grey + green)

Removal or relocation

Managed retreat

By 2002, historic Clavell Tower was deemed to be at serious risk of collapsing under the crumbling Dorset coastline at its base. The most technically, socially, and financially feasible solution was to simply dismantle the empty tower and reconstruct it further away from the cliff’s edge on more stable footing. This resulted in a reinvigorated heritage site saved from the dangers of coastal erosion.

Based on information from The Landmark Trust

General description

Located high on a cliff on the Dorset coast of southern England overlooking Kimmeridge Bay, Clavell Tower is a four story circular tower originally built in 1830. The soft and easily erodible shales of the cliff had been steadily crumbling and retreating towards the tower since its construction.

The responsible organisation for managing Clavell Tower, the Landmark Trust, decided that the most feasible solution for this kind of coastal erosion threat was to dismantle the ageing tower and re-erect it on a more stable base further away from the cliffs edge.

The eroding coastline for which Clavell Tower calls home happens to be a UNESCO World Heritage Site known as the Jurassic Coast. It is a popular tourist destination for its natural beauty and geological significance. As such, it is unlikely that more intrusive coastal erosion measures that could be used to stabilize the cliff would be approved. Relocating the tower itself was a more socially acceptable solution.

Innovative & Cost-effectiveness aspects of the measure

Dismantling and re-erecting Clavell Tower was simply the most technically and financially feasible solution for the Landmark Trust to undertake. Four years of fundraising efforts and external funding from the Heritage Lottery Fund allowed the project to commence by 2006. To offset some of the costs and ensure future revenue for maintenance and heritage preservation, the Landmark Trust also currently manages Clavell Tower as a hotel.

This kind of heritage conservation strategy is clearly the most intrusive possible and would not have been undertaken if it was not the most suitable option. Conservation staff carefully recorded and surveyed all the physical aspects of the tower so that the replication was as true to the original as possible. Sightlines from the tower across the bay and landscapes were also replicated as best as possible when orienting the tower in the new location. Lastly, the new tower was built in such a way as to allow additional future relocation should the eroding cliff’s edge make it necessary again.

Key lessons learnt

Even in heritage conservation, where intrusion and alterations are avoided whenever possible, sometimes drastic measures must be taken to combat the threat of coastal erosion. Relocating heritage sites to safer ground is a suitable solution, especially when the eroding coastline is deemed globally significant and has challenging terrain. Dismantling and re-erecting Clavell Tower was not a decision taken lightly, but it has proven to be a successful measure in preserving the tower’s positing as a valued historic landmark on a World Heritage Site.

Relevant case studies and examples

Exposed element relocation and removal

Measure category

EXAMPLE: Seawall at Skara Brae, Scotland (UK)

nst — Tue, 24 Jan 2017 08:37:41 +0000

EXAMPLE: Seawall at Skara Brae, Scotland (UK) nst Tue, 01/24/2017 - 09:37

Skara Brae is one of Scotland’s most significant and famous UNESCO World Heritage Sites and it has been under constant threat of damage due to coastal erosion for decades. Fortunately, a seawall protects the base of this archaeological site from the erosive power of waves and storm events.

Based on information from Historic Environment Scotland and UNESCO World Heritage Centre.

General description

The 5000 year old settlement of Skara Brae is one of the four monuments that make up the Heart of Neolithic Orkney, a UNESCO World Heritage Site. It is also quite possibly one of Scotland’s most at-risk historic sites due to coastal erosion. Ironically, Skara Brae was only discovered as a result of coastal erosion from major storm events since the 1800’s.

The risk of coastal erosion to Skara Brae was addressed in the early days of its heritage management. The first seawall was constructed in the late 1920’s, and has been refortified several times since then. Like all seawalls, this 4-meter high wall serves as a protective barrier that is able to absorb the brunt of wave action and thereby shield vulnerable infrastructure, or in this case archaeological structures, from eroding.

Historic Environment Scotland, the public body responsible for managing Scotland’s heritage sites, has been over the years maintaining the integrity of the wall, with the support of other organizations. There has also been extensive monitoring of the entire bay area to determine the rate and location of erosion so that additional fortification can be made. Skara Brae is a cherished piece of Scotland’s history and therefore has much public support for protection from coastal erosion.

Innovative aspects

Considering the early adoption of a seawall protection measure for Skara Brae, Scottish authorities have been quite proactive in ensuring the long term reduction of coastal erosion at this heritage site. With the first wall erected in the late 1920’s, this measure was a relatively pioneering tactic for heritage conservation. Today, Historic Environment Scotland has also employed the latest technologies of 3D and 4D digital surveying to monitor the state of erosion along the coast and measure the ongoing effectiveness of the sea wall.

Key lessons learnt

When it comes to vulnerable heritages sites along eroding coastlines, time is of the essence. While powerful storms throughout history revealed the existence of Skara Brae to the world, these same storm events and constant wave action threaten the longevity of the site as a place for future generations to enjoy. The prompt action of Scottish authorities to construct a seawall to protect the archaeological site decades ago has since been proven to have been a wise decision. Knowing what we know about the possibility of more hidden archaeological sites in the area, it is important to continue the monitoring efforts to not only assess the stability of Skara Brae, but also the impacts of the seawall as an element of the natural environment. The Bay of Skaill is a dynamic and ever changing system, and it is possible that the seawall might increase erosion from intensified wave action on the unprotected sand dunes on either side of Skara Brea.

Relevant case studies and examples

Seawall or Revetment

Further Readings

BBC report on Skara Brae

Measure category

EXAMPLE: A participatory adaptation planning approach, Cascais (PT)

nst — Wed, 18 Jan 2017 08:42:04 +0000

EXAMPLE: A participatory adaptation planning approach, Cascais (PT) nst Wed, 01/18/2017 - 09:42

Urban floods

Public Awareness and Preparedness

Non-structural measure

Cascais is a Portuguese city on the Atlantic coast and 30 km west of Lisbon. Within the project BASE, researcher supported the participatory ICZM approach to develop a Climate Adaptation Action Plan.

Based on: Ng, K., Campos, I., & Penha-Lopes, g. (Eds.) (2016): BASE adaptation inspiration book: 23 European cases of climate change adaptation to inspire European decision-makers, practitioners and citizens. Lisbon: Faculty of Sciences, University of Lisbon.

General description

Cascais is a Portuguese city on the Atlantic coast and 30 km west of Lisbon. Flash flooding is of especially high concern due to extensive urbanization in areas with strong economic and touristic activity and concentrated physical capital, namely historical buildings. In the period between 2000 and 2011, there was just over EUR 1 million in private claims to insurance companies, with 40% of that value occurring in a single event in 2008 in two parishes. In the same year, annual private costs due to flooding in Cascais exceeded EUR 400,000.

The Adaptation Response

In 2010 the municipality developed its Strategic Plan for Climate Change Adaptation (PECAC). In 2013-15 under the FP7 BASE project, a comprehensive participatory revision of the Plan was made together with the Agenda 21 of Cascais in order to reassess and reprioritize the implemented adaptation measures, taking into consideration all major stakeholders as well as all key affected sectors. Cascais is moving towards the updated Climate Adaptation Action Plan in 2017. The measures included :

green spaces and corridors in urban areas;
beach and shoreface nourishment;
the rehabilitation and restoration of rivers;
the establishment and restoration of riparian buffers; and
awareness campaigns for behavioural change.

The People and Institutions involved

Participatory methodologies have been extensively used in the Cascais adaptation strategy. BASE research work in Cascais began in October 2012 with preliminary/exploratory meetings with representatives from the municipality. Through nine participatory workshops, one population-wide inquiry (n=1885), one inquiry to the technical body of the municipality (n=99) and several field visits, PECAC 2.0 was completed in 2015. This makes Cascais BASE’s case study icon in the use of participatory methodologies.

Outcome of action

In terms of concrete measures, green corridors, rainwater gardens and rainwater catchments are to be implemented. Green corridors and the re-naturing of Cascais streams is an ongoing adaptation measure that enjoys wide stakeholder consensus and yields positive externalities and socio-political support with relatively low levels of investment needed. Yet its effectiveness in flood risk reduction in this specific case study is still uncertain and a detailed action plan is needed for further analysis.

Key lessons learnt

Climate change adaptation has to do with political choices and is not only a matter of finding the right technical solutions. Participatory experiences such as those developed in, Cascais or Timmendorfer Strand, show that adaptation decisions are political in nature, because they affect different stakeholders and citizens in different ways.

A number of regulatory frameworks and policies can either hinder or promote local action. One important strategy is to involve a wide range of stakeholders and citizens at the early stages of making decisions about measures. Practitioners and decision-makers need to be well informed on local, national and supranational policies, taking stock of potential synergies and addressing potential bottlenecks and constraints posed by public policies.

Relevant case studies and examples

Spatial Planning and Integrated Coastal Zone Management (ICZM)

Further Readings

The BASE project

Case Study report about Cascais

Literature sources

Ng, K., Campos, I., & Penha-Lopes, g. (Eds.) (2016): BASE adaptation inspiration book: 23 European cases of climate change adaptation to inspire European decision-makers, practitioners and citizens. Lisbon: Faculty of Sciences, University of Lisbon. http://base-adaptation.eu/sites/default/files/BASE%20Inspiration%20Book.pdf

Measure category

EXAMPLE: Coastal setbacks on the island of Kauai (USA)

nst — Mon, 16 Jan 2017 13:34:18 +0000

EXAMPLE: Coastal setbacks on the island of Kauai (USA) nst Mon, 01/16/2017 - 14:34

Channel, Coastal and Floodplain Works

Avoidance

Managed retreat

Coastal and river setbacks

On the island of Kauai, Hawaii in the USA, the local governing county has implemented flexible and protective coastal setbacks that protect communities from coastal erosion and avoid shoreline armouring in the long term.

Based on J.F. O’Connell et al. (2010): "The island of Kauai, Hawaii's progressive shoreline setback and coastal protection ordinance" In: Shifting Shorelines: Adapting to the Future,The 22nd International Conference of The Coastal Society , June 13-16, 2010 ,Wilmington, North Carolina.

General description

In this particular case, there is a disconnect between state regulations on coastal zone management and local or County regulations. In Hawaii, there are state laws that require setbacks along shorelines that are no less than 20 and not more than 40 feet inland from the shoreline and armouring the shoreline is permitted. The regulations at the state level, have however, led to inappropriate constructions in areas that jeopardize the island’s valuable sandy beaches. Thus in spite of an innovative and flexible Ordinance developed in 2008 called the ‘Shoreline Setback and Coastal Protection Ordinance’, the state still allows armouring.

The Ordinance puts into place procedures establishing minimum construction setbacks based on average lot depth and long-term shoreline erosion rates that are generated by the University of Hawaii.

The objectives of the Ordinance are manifold:

To provide a buffer zone to protect shorefront development from loss due to coastal erosion for a period of time;
To provide protection from storm waves;
To allow the natural dynamic cycles of erosion and accretion of beaches and dunes to occur;
To maintain beach and dune habitat;
And to maintain lateral beach access and open space for the enjoyment of the natural shoreline environment.
To avoid armouring or hardening the shore which along eroding coasts has been documented to ultimately eliminate the fronting beach.
The Island of Kauai is a county within Hawaii and is also the fourth largest of the Hawaiian islands. It is vulnerable to a variety of coastal hazards including inundation, erosion, hurricanes, and tsunamis.

Local Setting

On the island of Kauai the coasts and sandy beaches are important to the economy and the community. Shoreline armoring as a measure for dealing with climate change can benefit coastal infrastructure but it can also threaten coastal marine habitats and beaches. The potential loss of sandy beaches due to coastal hardening is particularly important in a state like Hawaii and specifically on Kauai where the local economy depends on tourism and beach activities.

In Kauai, the county takes the state wide implemented setback of 40 feet as a minimum standard and finds flexible and specific setback lines based on average lot depth and long-term coastal erosion rates that are developed and provided by the University of Kauai. The county, therefore, has taken steps to avoid shoreline armoring and establish safe and environmentally effective setback distances for construction of structures with a 2008 Ordinance. However, the regulations developed at the County level do not match those set by the state.

Political setting

The Kauai case study provides an example of when different levels of government set different regulations that are in conflict with one another. In Kauai, a local level Ordinance has set environmentally protective standards in place that go further than State coastal zone management laws to ensure the integrity of Kauai’s sandy beaches. While the State sets general measures for coastal setbacks and infrastructure development, the County appears to be setting up legislation that is more accurately informed by local circumstances and data and that prioritizes environmental considerations.

The Ordinance puts into place procedures establishing setbacks that go beyond the state-wide laws. The County setbacks also consider lot depth and long-term shoreline erosion rates. In order to determine the erosion rates of different areas around the island, the County has partnered with the University of Hawaii Sea Grant College Program to conduct an assessment on Climate Change and Coastal Hazards in Kauai and to provide data regularly.

Innovative aspect

In Kauai, the county takes the state wide implemented setback of 40 feet as a minimum standard and finds flexible and specific setback lines based on average lot depth and long-term coastal erosion rates that are developed and provided by the University of Kauai. For existing structures 20 feet is the minimum setback area. It also requires lot depths of greater than 160 feet with a proposed building footprint less than or greater than 5000 square feet to calculate the setback by multiplying the erosion rate by 70 or 100, respectfully on top of a forty food safety buffer.

The purpose of the Ordinance is to ensure that structures are not built in areas that are vulnerable to hazards and that shoreline hardening is avoided and not depended on to protect property during its lifetime. There are also specific rules regarding activities and structures that are allowed within the setback are, however, no structure approved within the setback area by variance will be eligible for protection by shoreline hardening.

Key lessons learnt

There are several interesting elements of the Kauai case study. Firstly, there is an inter-change between local levels of the island County and established state laws on zoning and management. The Ordinance that determines county rules for setback measures is more protective and exact in determining the rules for building and at the same time was designed in a way that is flexible to specific projects and also informed by local data and research. The partnership between the County and the University of Kauai to establish appropriate setback measurements based on erosion rates on the island illustrates the importance of partnerships between governing entities and institutions with relevant scientific data and knowledge. Finally, the Ordinance is designed to be somewhat flexible but is ultimately environmentally focused in protecting the integrity of sandy beaches and avoiding the hardening of the coast in the future to protect any existing structures.

Relevant case studies and examples

Further Readings

More information from NOAA

Literature sources

O'Connell, James and Aiu, Imaikalani and Milnes, Leslie and Smith, Lisa Ellen (2010) The island of Kauai, Hawaii's progressive shoreline setback and coastal protection ordinance. In: Shifting Shorelines: Adapting to the Future,The 22nd International Conference of The Coastal Society , June 13-16, 2010 ,Wilmington, North Carolina

O'Connell, James et al. (2009): A PROGRESSIVE, BALANCED COASTAL CONSTRUCTION SETBACK ORDINANCE ON THE ISLAND OF KAUAI, HAWAII: IMPLEMENTATION AND LESSONS LEARNED. Proceedings of Coastal Zone 09, Boston, Massachusetts, July 19 to 23, 2009

Measure category

EXAMPLE: Relocation in Criel sur Mer, Normandy (FR)

nst — Mon, 16 Jan 2017 12:49:39 +0000

EXAMPLE: Relocation in Criel sur Mer, Normandy (FR) nst Mon, 01/16/2017 - 13:49

Channel, Coastal and Floodplain Works

Managed retreat

Exposed element relocation and removal

Criel sur Mer is a small town in Normandy in the region of Northern France, known for its stunning coastline of steep chalk cliffs. Erosion of the cliffs in Criel sur Mer is occurring rapidly as a result of climate change but also due to man-made construction works further up the coast. In Criel sur Mer a short piece of land on the coast that is eroding rapidly and several homes built near the sea are threatened by the predicted collapse of the cliff. In particular, a street of homes were faced with immediate danger from erosion. Between 1995 and 2003, the local administration organized the abandonment and demolishment of 14 homes due to imminent risk from natural disaster under the Barnier Law. The adoptive policy was to do nothing against cliff erosion and to demolish and relocate those in immediate threat and compensate them fairly for their lost property.

General description

Coastal erosion is a common challenge along many stretches of the coast in Normandy. The cliffs are extremely steep and the rock material is chalk which is soft and easily erodible. The verticality of the cliffs mean that erosion is especially intense at the base of the cliff leading to significant fractures and collapse of cliff and loss of pebble beaches that would otherwise help mitigate erosion from the sea. Moreover, in Criel sur Mer considerable engineering works carried out along the coast have exacerbated erosion. Specifically, the construction of the ports Le Havre, Fécamp, Saint-Valery-en-Caux, Dieppe, and Le Tréport as well as structures for water and nuclear stations in Paluel and Penly; and the creation of coastal defence structures (sea fronts, groynes etc) at the mouths of all the valleys. These manmade constructions have created disturbances to the transport of sediment (mainly course pebbles) to the shore and resulted in a faster rate of erosion due to lack of protection. Pebbles have also been extracted for gravel purposes. Loss of pebbles leads to a retraction of the beach which protect the mouths of the rivers and the cliffs.

One of the immediate challenges for the community of Criel sur Mer was the actual loss of cliffs where houses existed.Responding to this emergency, the local administration considered both hard and soft measures with for instance the consideration of the implementation of defence works at the base of the cliff. The high cost of defence measures and the low cost of the real estate threatened by erosion led the local administration to evacuate the families faced and to implement a coastal setback plan whereby any new developments must take place 100 m from the cliff top.

The innovative aspect of this relocation measure was the fact that the compensation rate to those individuals that lost their property was calculated against the real market value. It is common that properties known to be at imminent risk lose real market value quickly, however, in the case of Criel sur Mer the French Government ensured that those families losing property were provided for financially based on the ‘riskless’ market value of the homes.

Key lessons learnt

The lesson of the Criel sur Mer illustrates is the inevitability of managed retreat in the face of climate change and the fact that multiple variables affect the situation and decision taken. For example, the cause of erosion was not only climate change but also a result of manmade constructions and attempts to mitigate against erosion. Moreover, the possibility of implementing a hard defense was considered but was economically disadvantageous. Thus, the Criel sur Mer provides an example of an extreme case of communities being threatened by climate change and provides an example of how governments and administration can more fairly compensate them economically.

Relevant case studies and examples

Further Readings

PDF: Geotechnical study

Scale

Local

Measure category