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CASE STUDY 02 COASTAL PROTECTION ON THE WEST OF , Public Disclosure Authorized CASE STUDY 02

Coastal Protection on the West Coast of Jutland, Denmark

change of policy and shifting to soft measures for coastal protection has safeguarded the socio-economic development of the local communities

Public Disclosure Authorized A to their exposure to the waves. Along the 70 km stretch, entailing the fjords1 of Ringkøbing, Nissum and Nissum , most of the are very narrow. They are only a few hundred meters wide or less.

Ringkøbing Fjord is Denmark’s largest fjord with an outlet to the North Sea at the Hvide Sande lock. It is a shallow brackish separated from the North Sea by a narrow -barrier. It serves as the fifth largest fishing port in Denmark. According to Ramsar, the site is an internationally important area for breeding, wintering

Dunes protect the hinterland and Lake Ferring against flooding and staging numerous species of waterbirds. Nissum Public Disclosure Authorized (Source: Kystdirektoratet) fjord is a shallow fjord area with and sandbanks. It has intertidal zones, salt marshes with brackish , Context meadows and reedbeds. The site is an internationally important area for breeding, wintering and staging of Denmark consists of the Jutland and more various species of endangered waterbirds such as Baltic than 400 , which represents more than 7300 km of Dunlin Calidris alpina schinzii and Ruff Philomachus coastline. The Western coast of Jutland faces the North Sea and is made up of sandy in front of series pugnax (Ramsar 2012). The site regularly supports over of ridges. The main watershed of the peninsula 20,000 staging waterbirds during spring and autumn lies towards the east coast. The western slope is gentle (Ibid.). Nissum Bay is the largest of the three and is and consists of a low sandy plain. connected to the North Sea by the Thyboron .

The coastal dunes in the west coast form a belt up to 10 km The west coast of Jutland is exposed to the North Sea wide. These dunes protect the hinterland against flooding. waves and vulnerable to . Along the However, they are particularly vulnerable to erosion, due coast, natural coast-erosion averages 2 m/year. Coastal Public Disclosure Authorized

1. Fjord is a long (narrow) strip of sea between steep hills, created by glacial erosion.

1 CASE STUDY 02 COASTAL PROTECTION ON THE WEST COAST OF JUTLAND, DENMARK

erosion also significantly reduces the protection of the Main Challenges hinterland against flooding, which once provided by the dunes. The west coast of Jutland is also more exposed The high vulnerability of the low-lying coastline to Rise (SLR), due to low-laying coastal areas combine with -physical condition, as well as storm The West Coast is sandy and particularly vulnerable to surges than the eastern part of the country, induced by erosion. It consists mainly of a sweeping line of dunes the changing climate. These hazards are increasing the with wide lagoons behind them. The seaward banks of the lagoons are frequently broken during storms, and the rate of erosion. The population density at the western narrow channels through them are constantly shifting. coast of Jutland may not be high (in average about 50 The hinterland is low, making it more prone to floods. persons/km2). However, many valuable recreational beaches are found at the western coast of Denmark. The average erosion rate of the west coast is from According to Ramsar Sites Information Services, five 2m to 4m per year, with a maximum of 11m per year. major conservation areas are located in the west coast, The erosion at the western coast of Jutland is mainly between Ringkøbing to Nissum Bay. Around two thirds wave-induced. The maximum wave heights can reach up of the land is used for agricultural production of intensive to 6 meters, with lengths vary from 350 to 1000 meters. cash crop and roughage. Although, over the last 50 years, A mean has been projected to be 0.15- agricultural land has decreased due to the expansion of 0.45m by 2050 and 0.30-1m by 2100, excluding vertical urban areas. Currently, around 80% of the population land movement. The maximum wind speed during lives in urban areas connected to the coast. The western storms is projected to increase between 1 and 10% by coast of Jutland area represents a high economic and 2100 (Pranzini and Williams 2013). Increased sea level environmental function. The level of coastal erosion rise coupled with increased storm intensity will further hazard, both wave- and climate change-induced, is increase erosion rates, especially along the western considered to be high. and northern coastline. With an approximate addition of erosion rate between 5.0-7.0 m/year in these parts.

Human-activities-induced coastal erosion Erosion rates on the Danish are exacerbated by human activities, mainly caused by unsustainable infrastructure development. In the early 19th century, the coastal dunes along the west coast of Jutland were stabilized through planting marram grass. However, with the continued construction of harbors and , high rates of down-drift erosion occurred. Eventually, traditional stabilization method, i.e. planting marram grass, could no longer be effective. It must be noted that marram grass rather serves as a buffer to resist storm erosion for the dunes, but may not be the most appropriate measure for the on-going down drift erosion. The situation was further exacerbated by the occurrence of a violent storm in November 1981, which eroded the dunes by more than 10m on average. In some places, erosion even reached up to 30m. The combination of both human-induced coastal erosion caused by infra- structure development and violent storm resulted in the disappearance of the dunes or severe weakening along 50km of the coast, in 1982.

Lack of knowledge and application of soft coastal protection measure

2 CASE STUDY 02 COASTAL PROTECTION ON THE WEST COAST OF JUTLAND, DENMARK

To maintain socio-economic development in the area, Major Activities hard structures were mainly used as coastal flood defense mechanisms. Towards the end of the 19th century (since With the alarming rates of erosion at the western coast 1875), groynes were the main method used for coastal of Jutland, in 1982 a coastal protection scheme was put defense and were built from granite and concrete. in place. The scheme highlighted the following activities: The local authorities believed these structures were the best solution for their problem (DVH 2010). It was 1. The Improvement of coastal protection governance. not until 1974 that sand nourishment, as soft measure, The policy for the safety assessment and erosion control was slowly being used. This was due to the growing (serve as non-technical measure) was established as an awareness among the general public and politicians, agreement between the local authorities and the national as well as a better understanding of the advantages of government, which was based on recommendations from soft measures in the long run, as well as the increased the Danish Coastal Authority. experience of the application of nourishment. The policy targets the following: Since 1982, engineering solutions have mainly shifted • To re-establish a safety level against flooding to a from hard to soft. minimum 100-year return period • To halt erosion especially in areas close to beach towns Policy Framework • To reduce erosion on the parts of the coast where In Denmark, the Coastal Protection Act, which is based erosion, in the near future, would reduce the hinterland on the first Dike Act of 1874 and subsequently on the safety against flooding to less than 100 years. Coastal Defences Act of 1922, regulates coastal protec- 2. Coastal Zone Management. A large scale, coastal tion. The overall principle regarding the implementation protection scheme was undertaken to ensure the safety and financing of coastal protection in Denmark is that of the coastline. The following technical measures have the landowner is responsible for protecting his own been employed: property. Measures must be initiated, financed and implemented by landowners or arranged for within the • Nourishments: The coast is nourished annually with municipalities. The Danish strict land-use planning limits sand from the North Sea, which is either dumped on the impact of flooding along the coastline. Danger to the sandbar or placed directly on the beach, to stop human life was deemed small and only land would be the coastline from receding further. Sand applied to damaged by erosion and flooding. Hence, there were the beach directly acts as standard beach nourish- no national rules for safety assessment of dikes and ment. Meanwhile, the sand applied underwater to dunes along the Danish coastline. the sand bar acts as a wave-breaker which reduces the wave intensity and thus coastal erosion, but also However, high rates of leeside erosion, exacerbated by a reserve of sand which might be brought to the the Harbor breakwater and large groups, were beach by the waves. presented at the western coast of Jutland. Therefore, a coastal protection scheme was implemented starting • Revetments: Reinforcement and construction of in 1982, and is continuing until today. This is the only new dunes were undertaken to re-establish the safety against flooding to a 100-year return period. part of the Danish coasts that receives financial support However, to ensure meeting the safety level required, from the national government. the authorities combined the implementation of soft and hard measures (revetments). As a slope protection measure, 25 km of revetments were built along the Objective of the coastal foot of the dunes. Combination of protection scheme and protection of dune’s foot with a revetment has raised safety level against flooding to a return period of more than 100 years. The initiative aimed to increase safety against coastal flooding, by assuring that erosion rate does not exceed • Detached breakwaters: In total, 145 breakwaters 5-7 m/year. To do so, an agreement on coastal protec- were constructed to reduce the required sand volume tion scheme in the west coast of Jutland was initiated for beach nourishment. Low detached breakwaters in 1982, involving respective municipalities, counties are used in combination with nourishment on highly and the state. exposed stretches where erosion should be stopped. 3 CASE STUDY 02 COASTAL PROTECTION ON THE WEST COAST OF JUTLAND, DENMARK

Results and impact Beach recovery • A change of policy and shift to a hybrid approach with Controlled erosion rate predominantly soft techniques, rather than application • Since 1983, the coastal protection of the 110 km of merely hard measures, has led to a situation where erosion is no longer a problem. It has aided the tourist stretch, from Lodbjerg to Nymindegab, has been industry by re-creating beaches and safeguarded the carried out in cooperation with the local authorities. It socio-economic development of the local communities. resulted in 28 km of slope protection, the construction of 145 breakwater, and coastal nourishment. Following these efforts, the works today almost only entails Adaptation to Climate Change nourishment. In recent years, beach nourishment has • Beach nourishment activity also provides opportunities increasingly been used to protect exposed stretches for continuous climate change adaptation. Especially of coastline. with the increased cooperation between the national authorities, municipalities and even individual own- • Erosion control, with a combination of nourishment ers. Danish coastal authorities allow site owners to (soft measure) and low detached breakwaters (struc- raise the beach at their own cost by regular beach tural measure), has reduced the coastal retreat to nourishment to combat coastal erosion. As such, it is 0.1 m/year (EC 2010). There is no such thing as zero beneficial for human and environmental protection erosion, however it has been “stopped” (by sand nour- against flooding risks. ishment) where it is important to protect the dunes.

• With the construction of the dunes, safety level Lessons learned (against coastal flooding) has been re-established to at least 100 years, achieving the goal set in 1982. To Controlled erosion rate date, there is no undesirable effect appearing outside • The coastal protection on the west coast of Jutland of the project area. Although locally, some leeside highlights that a combination of hard and soft measures erosion still occurs downstream of the detached have been able to reverse the trend of erosion with breakwaters and revetments, this is a phenomenon limited effects elsewhere. The use of breakwaters has that can be controlled. reduced the need for nourishment landward by 50%. 4 CASE STUDY 02 COASTAL PROTECTION ON THE WEST COAST OF JUTLAND, DENMARK

• Beach nourishment was found to better stabilize cost (excluding supervision and pipe maintenance the coast in the first year. It must be done to serve cost) (Thyme 1990): as a buffer and prevention to erosion of the dunes - Excavating and loading of sand from the beach: during storms. However, for the long run, sand-bar 0.75 US$/m3 nourishment is good for coastline stabilization and - Dumping of sand on the bar: 2 US$/m3 more cost effective in the case of Jutland. - Pumping through the pipe on to the beach: 3 US$/m3 - Transportation of sand (between 2-4 km): 1.5 US$/m3 • Political willingness coupled with close cooperation between responsible parties, i.e. the government, • As for the annual sand nourishment in the following local authorities and site owners, provides a “win-win years about 1,200,000 m3 is required annually. solution” to accelerate the process of protecting the hinterland against flooding. Furthermore, it helped to According to a recent study , maintenance expenditures protect the vital socio-economic elements of the area. for Jutland coastal protection measures (mainly beach nourishments) amounted to 255.5 million euros for the • Appropriate funding has been a key. Political and period 1998-2015. Over the same period (1998-2015), public awareness combined with the availability of Denmark spent about 315 million euros (capital and funding support from the central government allow maintenance expenditures) to protect its coasts from possibility to do something new, while “breaking the flooding and erosion. habit” of using hard measures that, in this particular • Despite the success of the coastal protection mea- context, were less efficient and effective. This entailed sures, the Danish Coastal Authority is continuously ‘learning by doing’ and basing new decisions on the optimizing the coastal protection effort on the west outcome of previous decisions taken i.e. adaptive coast. The annual coastal protection scheme for the management. West Coast is planned through the use of surveys, • As an initial step, about 300,000 m3 of sand were measurements and the analysis of coastal develop- pumped to nourish the beach, with the following ments from the preceding years.

REFERENCES

• ClimateChangePost. Coastal Erosion Denmark. in-denmark.html (accessed March 10, 2017) 2015. http://www.climatechangepost.com/ • Coastal Protection on the West Coast of Jutland. 1 denmark/coastal-erosion (accessed March 11, June 2015. http://eng.kyst.dk/coastal-protection- 2017) on-the-west-coast-of-jutland.html (accessed March • DVH. “Western Coast of Jutland.” Eurosion. 2010. 10, 2017). http://copranet.projects.eucc-d.de/files/000111_ • Pranzini, Enzo, and Allan Williams. Coastal Erosion EUROSION_West_coast_of_Jutland.pdf (accessed and Protection in Europe. USA: Routledge, 2013. March 10, 2017) • Thyme, Flemming. Beach Nourishment on the • Kystdirektoratet. Coastal Protection in Denmark. 1 West Coast of Jutland. Denmark, 1990 June 2015. http://eng.kyst.dk/coastal-protection-

The West Africa Coastal Areas Management Program (WACA) is a convening platform that aims to assist West African countries to sustainably manage their coastal areas and enhance socio-economic resilience to the effects of climate change. The program also seeks to facilitate access to technical expertise and financial resources for participating countries. www.worldbank.org/waca 5