The purpose of this research is to present design strategies to enable coastal areas to adapt to climate change and maintain the coastlines by addressing the environmental and urban issues. Gangneung is a tourist attraction situated on South Korea’s east coast, and there is an urgent need for integrated research on strategies to prevent the loss of sandy beaches and the damage caused by storm surges and high swell. This research has two objectives: The first is to offer an overview and describe the characteristics of exemplary projects carried out to manage the storm damage while maintaining the coastlines. The second is to propose a design model that can be applied to coastal areas susceptible to climate change by analyzing the design strategies and the current conditions of the Gangneung coastal area. In the case of Gangneung, the damage caused by the storm surges and high swells are more severe compared to inundation caused by sea level rise because of the steep slope and deep water. Therefore, adaptive design strategies are mainly focused on accommodation and retreat strategies that consider these characteristics by moving the coastal roads behind the pine forest and raising the coastal buildings to connect the coast to the forest and to prevent coastal erosion. This research has the potential to be used as an exemplary design adaptation for coastal erosion as well as a basis for regulating the land use policy in areas susceptible to flood by establishing guidelines for publicly funded developments, and preparing long-term relocation plans for the existing coastal developments to create a sustainable and resilient future for the coastal areas.
The need for design strategies in coastal areas to adapt to climate change has become a worldwide priority [
While previous research has focused on the categorization of the methods and planning strategies of adaptation to rising sea levels for the coastal cities [
Previous research categorized the adaptation strategies responding to rising sea levels with axonometric diagrams including the representative systems and site advantages as shown in
Strategies | Features | Methods | Site advantages | Diagrams |
---|---|---|---|---|
Hard protection | Dikes Levees Sea walls Groins | Build physical barriers to block water | For hard-to-move facilities and infrastructure on flat grounds | |
Soft protection | Mangroves Wetlands Sand dunes Tidal flats | Create buffer with vegetation or landforms | For maintaining the shoreline on the site with existing coastal forest or sand dunes | |
Accommodation | Raising levels Desalination Drainage Alarm system | Upgrade functions while retaining the location | For redevelopment projects or facilities on the site without high grounds nearby | |
Retreat | Relocation Abandonment | Relocate facilities to low-risk uplands | For residential and public use facilities on the site with low-risk uplands nearby |
Projects | Cleveleys Sea Wall Lancashire, England | Wahyun Village, Geoje, Korea | Lifting Houses, New York and New Jersey, USA |
---|---|---|---|
Objectives | Creating protective buffer with vegetation or landforms | Relocating the facilities from high-risk coastal area to low-risk uplands | Upgrading the function while retaining the current location |
Strategies | Hard/Soft Protection | Retreat | Accommodation |
Methods | Minimizing the division between the village and the coast by improving the coastal scenery and creating interrelated public spaces | Demolishing the damaged coastal residential area and creating a new residential complex in a safer hilly area | Raising the building along the coast to withstand the storm surges and temporary inundation |
Project images | |||
For the town of Cleveleys in Lancashire, United Kingdom, a new sea wall was designed to address the visual unattractiveness of the existing sea wall and to prevent the division between the town and its coast caused by the previous wall. The newly created sea wall was designed to provide a high-quality coastal space that would also protect the town from storm and flood, and furthermore, it became a new tourist attraction contributing to their local economy [
Wahyun Village of Geoje, Korea, suffered significant damage due to a typhoon called Maemi to the extent that the majority of houses on the coast were destroyed. Owing to government support, widespread public encouragement, and local residents’ participation, the relocation project to move the old village toward uplands away from the seaside was completed in 4 years [
Many coastal houses in New York and New Jersey have been damaged by Hurricane Sandy in 2012. The adaptive action taken to prevent flood damages and preserve the coastal communities involved lifting the buildings using pier structures. This remedy enables the residents to obtain the elevation certificate in order to mitigate future insurance claim for flood damage [
These exemplary projects were implemented in response to storm damages, and they provided relevant ideas for the adaptive coastal design. Cleveleys Seawall utilized the landform as a protective buffer minimizing the division between the village and the coast by improving the scenery and creating interrelated public spaces. Wahyun Village was relocated from its highly vulnerable location in the coast to the low-risk uplands. Projects that involved lifting the houses upgraded the low-elevation houses along the coast to withstand storm surges and temporary inundation. Through these case studies, this research focused on three adaptive design strategies for the coastal area-soft protection, retreat, and accommodation-and investigated the possibility of defensive coastal designs considering the current storm damage as well as future climate change.
The east coast of Korea runs from the inlet of the Tumen River to Busan Quays, which is 1723 km long, and the section belonging to Gangwon Province is 318.3 km long, approximately 18.4% of the total length [
While multiple scenarios of rising sea levels are under investigation, this research took its core data from the inundation map created by the Korea Environmental Institute (KEI) in 2012 by considering the storm surges based on the prediction that sea levels will rise by 1.36 m by 2100. The land cover map used in this research was produced in 2007 and modified in 2009. The medium classification land cover map developed by the Ministry of Environment and a digital map based on the ITRF 2000 ASTER DEM map were also used.
There are a number of sandy beaches and cities along the ports throughout the coast in Gangwon Province as shown in
The Yeongdong region consists of coastal areas on the east side of Daegwallyeong Ridge in the Tae baek Mountains as shown in
high mountains on the landward side and located along the shoreline for their association with traditional ocean-related industry. For this reason, the physical expansion of cities and the growth of facilities caused by urbanization and industrialization have had a direct impact on the seashore.
Over the 43 years from 1964 to 2006, wave heights of the east coast have reached 7 m, as the sea level of the east coast has risen by 22 cm. However, sea walls are only about 4 to 5 m high in the majority of ports on the east coast as they were built based on the heights of waves when designs for ports and coastal structures are set up in 1988. Thus, damage from flooding and erosion is increasing since overtopping occurs even during storms or heavy rain, let alone during powerful typhoons [
In contrast to the southwest coast where reclamation projects have been implemented relying on the rias shoreline and the widespread tidelands, the shoreline of the east coast is well-defined and water depth is high while the movement of sand caused by waves dominates the beach development. Because the slope between the land and the ocean is steep, the seaside on the east coast mainly consists of sand and rock cliffs, and tidal mudflats have not developed. As indicated by the characteristics of the east coast, coastal erosion due to high waves is a major problem in the coastal areas of Gangwon Province, and 18 out of 34 sandy beaches on the east coast are severely eroded as shown in
To analyze the erosion in the coastal areas of Gangneung, the largest coastal city in Yeongdong Region of Gangwon Province, two coastal areas with accelerating erosion problems were selected as research sites. The proposed design focuses on moving the shoreline roads as well as the residential and commercial areas adjacent to the coastal in land in order to prevent coastal erosion by facilitating the natural influx of soil and sand. The sys- tematic adaptation plans for each area were created to reveal the topographical relationships and material move- ments of each area. The mean sea level of the section diagram was set according to the mean sea level in 2009, and the expected sea level was predicted by taking into account a sea level rise of 1.36 m along with storm surges.
Youngjin is a small village in the northern part of Gangneung; approximately 60 households are engaged in fishery business utilizing the nearby Youngjin port. To protect the port from storm surges, lengthy sea walls, sand groins, and lighter’s wharves were recently built in this port. Since the construction of these protective structures, tidal currents and sand flows have changed the sedimentation patterns blocking the port entrance.
The beaches at Youngjin and Yeongok are located in the north and south of the port, respectively (
The main design strategy for this area is to reconnect the pine forest and the beach to allow the circulation of sand as shown in
Geumjin Beach is 900 m in length, 50 m in width, 45,000 m2 in area, and can accommodate 22,500 people. A shoreline road on the sea wall was developed along the beach, and the other side of the shoreline road is a small fishing town and the mountain behind it (
The proposed design involves raising the coastal buildings to circulate water and sand. When the shoreline roads are relocated behind the raised buildings, they can be directly accessed from the building level because of the steep topography of the east coast. At the front of the coastal buildings, boardwalk promenades can facilitate the pedestrian access for residents and visitors while allowing the influx of water and sand as well as preserving the coastal scenery as shown in
This research analyzed physical and environmental characteristics of Gangneung’s coastal areas, situated on the east coast of Gangwon Province in Korea. Gangneung is susceptible to the effects of climate change, and the erosion damage from the storm surges and high swells are expected to be more serious problem than the inundation because of topographical and oceanographic characteristics of the east coast. Therefore, the adaptive design strategies are mainly focused on the accommodation and retreat strategies in order to maintain the coastlines.
The main aims of this research are to review the adaptation strategies in response to climate change through case studies and apply the findings to new research cases, and to analyze the research areas that are susceptible to climate change and propose adaptive design strategies through diagrams and three-dimensional representa-
tions. Youngjin and Geumjin Villages in the coastal areas of Gangneung were selected as research sites to experiment adaptive design strategies in response to climate change and rising sea levels. The design strategies for the adaptation are as follows: 1) for both areas, the shoreline roads adjacent to the coast are to be moved behind the pine forest to connect the forest to the beach; and 2) the coastal buildings are to be raised in order to prevent coastal erosion by facilitating natural influx of soil and sand.
This research has considerable potential to be used as an exemplary design adaptation to climate change for coastal areas. The research attempts to provide a basis for the land use policy in areas susceptible to erosion and flooding, to establish the guidelines for publicly funded developments, and to prepare long-term relocation plans for existing coastal developments in order to create a sustainable and resilient future for the coastal cities.
The result of this research was initially presented in the report, National Assessment on Sea Level Rise Impact of Korean Coast in the Socioeconomic Context II, published by the Korea Environmental Institute in 2012. The author is grateful to the Korea Environment Institute for funding this research, and particularly Dr. Kwangwoo Cho, for providing related data including the inundation map. Graphic production and data collection for this research were supported by graduate students in Evolving Landscape Laboratory. The author thanks all participants for their assistance.
Yumi Lee, (2015) Protecting the Coastline from the Effects of Climate Change: Adaptive Design for the Coastal Areas of Gangneung, Korea. Journal of Building Construction and Planning Research,03,107-115. doi: 10.4236/jbcpr.2015.32011