Hard Engineering Structures Research Articles

Experimental study on wave damping potential of seaweed aquaculture systems on the Portuguese coast

The sea-level rise and intensification of extreme weather events pose a significant threat to coastal regions and their communities worldwide. With significant wave heights reaching over 5 m, and wave periods over 10 s (Mendes & Oliveira, 2021), the Portuguese coastline is exposed to major coastal erosion, due to the marine harsh conditions of the North Atlantic. In the last decades the preferred strategy to protect the coastline from coastal hazards has been the construction of hard-engineering structures such as seawalls and breakwater, which tend to be expensive and unsustainable, often becoming obsolete and were not designed to account for the increasing sea level. As such, there has been a growing trend over the adoption of soft, adaptative, and nature-based coastal protection measures (Pranzini et al., 2015). Longline seaweed aquaculture systems have long been identified as a nature-based, soft structure with wave damping potential by several studies performed by Mork (1996), Liu et al. (2015) among others. The AquaBreak Project aims at exploring the synergetic applications of seaweed aquaculture systems on food production, coastal protection, and sea decarbonization on the Portuguese coast with the creation of the AOS - the AquaBreak Offshore System (Miranda et al., 2023; Proença et al., 2023). However, in order to create a strategic and effective implementation plan for the AOS, it is important to assess the wave damping potential of such structure exposed to the common maritime conditions of the Portuguese Coast.

Sand dune restoration as sustainable natural architectural design for coastal protection along seasonal storm-prone beach

Monsoonal storms cause coastal erosion of worldwide sandy beaches, including coasts in Malaysia. Although hard engineering structures are effective in mitigating erosion, those constructions can create several environmental issues such as down-drift erosion. The Effective Sand Fence (also known as E-Fence) is considered one of the sustainable alternative structures to protect beach erosion. Therefore, the objective of the current study is to identify the effectiveness of E-Fence for dune restoration. In this study, we measured beach profile survey, grain size distribution, and wind speed. In addition, XBeach simulation was used to determine sediment accumulation under the E-Fence protection. Results of the beach profile survey (i.e., slope and dune volume) indicate dune restoration in protected areas of the E-Fence. Grain size distribution and wind speed suggest the decreasing of wind velocities from the swash zone to the backshore. Accordingly, the E-Fence acts as a barrier, and the reduction of energy leads to accumulate sediments by passing through gaps in the structure. The E-Fence is thus capable of sustaining against wave attack and can maintain stable coastal ecosystems. Consequently, this coastal protection structure assists in developing cheaper coastal erosion mitigation strategies in Malaysia and elsewhere.

STRENGTHENING COASTAL DEFENCE WITH ARTIFICIAL DUNES

The Belgian coast is primarily sandy and is locally subject to erosion (Deronde, 2004). Traditionally, erosion was counteracted using hard engineering structures like groynes, seawalls and sea dikes. Nowadays, the Belgian government uses a different strategy by adopting a more soft and dynamic approach where possible. Many ‘soft’ managing activities at the Belgian coast are carried out in the form of regular and routine sand nourishments to cope for future flooding risks and coastal erosion (Houthuys, 2012). This method gives room to a new approach for coastal management where the natural elements and processes facilitate the development of new engineered dune areas at locations where traditional dike structures currently protect the hinterland. In the context of climate change and strict requirements for water safety, these hard to adapt engineering structures will not resist future flood events and more innovative solutions like dune in front of a dike principles to deal with rising sea level are receiving considerable attention. As a result, concepts are worked out in which traditional sea dikes are reinforced with newly created dune systems, offering a high level of protection of coastal infrastructure and at the same time offering a more natural appearance and higher ecological and socio economical values. In the framework of the SARCC project, one pilot site is realized in Raversijde. Besides the coastal defense function of the artificial dune, a second benefit is achieved: mitigating the nuisance, created by aeolian sand transport and preventing roads and tram tracks at the dike crest to be buried in sand.

Remotely operated vehicle reveals fish orientate to the substrate underneath marina floating pontoons

The modern day seascape is a mix of natural habitats (saltmarsh, mangroves, seagrass, unvegetated beaches), but increasingly is being replaced with hard engineering structures (e.g. floating pontoons) that have resulted in novel habitats available for flora and fauna. While these engineered structures provide new marine habitat resources, from the viewpoint of biodiversity, they effectively support a sub-set of species found in natural habitats. Unlike previous studies that have used divers for fish visual census, we used a remotely operated vessel with an underwater camera to examine the fish community using floating pontoons in a marina facility in tropical central Queensland, Australia. The camera filmed continuously the edge and underside of pontoons (both surveys covered similar pontoon linear distances – July (winter) 430m; November (summer) 485m; 2021). Fifteen fish species representing 14 families were recorded, with more species observed during summer compared to the winter survey. Remarkably, across both surveys of the 243 fishes individuals that were recorded, 166 (68%) appeared upside-down in videos (i.e., oriented to the underside of the pontoon). Engaging a behaviour of swimming upside-down has been acknowledged in natural habitats elsewhere; some coral reef species living in caves or reef ledges orientate themselves to the cave ceiling or overhanging ledge to increase prey capture rate. However, this is the first study to record fishes exhibiting the same behaviour. We conclude that our less invasive video survey approach provided the opportunity to observe fishes in a state of natural behaviour, orientating themselves towards the pontoon substrate, which is probably simply a response of adhering to basic characteristic modes, i.e., it is the orientation relative to the substrate that is important, rather than their orientation in space per se. Indeed marina pontoons provide an additional feature in already habitat complex estuaries; these data add to why we need to consider the ecosystem services offered by marine infrastructure, and the plasticity of fish to adapt to new environments in an expanding blue economy.

Impact of coastal structure on shorelines along the southeast and southwest coasts of india

ABSTRACT This study aims to explore the site-specific impact of coastal structures on the stability of the shoreline. For this study, the shoreline data were collected with higher-order accuracy along a few vulnerable stretches of the coast in the vicinity of hard structures such as Seawalls, Groyne, Breakwater, and Training walls along the southeast and southwest coasts of India. All the field collected shoreline data were analysed with statistical measures using DSAS (Digital Shoreline Analysis System) tool of ArcGIS software. The presence of shore connected coastal structures dictates the sedimentation process in its purlieu. The observed average rate of erosion and accretion in the adjoining coastlines are −5.7 m/yr and +4.92 m/yr, respectively. The field measurements from the present study would provide an effective base for the planning and implementation of coastal structures near the studied area, as well as to adopt a better methodology for coastal impact assessment. Most of the well-planned and executed hard engineering structures have yielded desirable results and benefit for the local coastal communities.

Coastal land use and shoreline evolution along the Nador lagoon Coast in Morocco

The coastal zone, a highly dynamic and complex environment, has important ecological and jurisdictional implications for governments and coastal managers. Based on the CORINE Land Cover classification system, this paper examined the effects of land use and land cover change (LULC) on the coastlines' dynamics along the ∼24 km barrier island of Nador lagoon on the Mediterranean coast of Morocco during a period of 62 years (1954–2016). The study utilized high-resolution orthoimages in the geographic information system (GIS) environment to characterize coastline evolution and LULC changes. The evolution of the coastline was assessed using a GIS tool, in particular the Digital Shoreline Analysis System (DSAS). The net rates of coastline change were calculated by using statistical methods: the End Point Rate (EPR) and the Linear Regression Rate (LRR). Results concerning the LULC changes showed that agricultural area and beach/dune classes decreased over the entire study period (62 years) by 11.14% and 28.45%, respectively. Urban fabric, shrub, forest, and saltmarsh/peat bog classes increased during the 62 years of evaluation by 2.69%, 19.92%, 16.77%, and 0.19%, respectively. Results regarding coastal analysis indicated that the accretion and erosion processes along the barrier island of the Nador lagoon (∼24km) were observed at 45% (10.6 km) and 55% (12.8 km) of the coastline, respectively. The beaches of Oulad Zehra and Oulad Aissa were characterized by erosion (−0.58 m/yr to −0.57 m/yr respectively), while accretion was observed on the beaches of Boukana and Kariat Arkmane at rates of +2.15 m/yr and +0.82 m/yr, respectively. This study highlighted that natural and anthropogenic processes have a strong influence on the erosion/accretion trends identified along the barrier island of Nador lagoon. The changes in LULC have affected the barrier island of the lagoon in two different forms: (1) a significant spatial conversion due to dune reforestation and (2) a fundamental spatial modification that affects the sea-lagoon connection (inlet) and the construction of new hard engineering structures.

On the use of large-scale biodegradable artificial reefs for intertidal foreshore stabilization

Combining foreshore ecosystems like saltmarshes and mangroves with traditional hard engineering structures may offer a more sustainable solution to coastal protection than engineering structures alone. However, foreshore ecosystems, are rapidly degrading on a global scale due to human activities and climate change. Marsh-edges could be protected by using connected ecosystems, such as shellfish reefs and seagrass beds, which can trap and stabilize sediments, thereby reducing hydrodynamics loads on the saltmarsh edge. In our study, we aimed to test the effect of large-scale biodegradable artificial reefs on tidal flat accretion and/or stabilization. We hypothesized that the structures would attenuate waves and trap sediment. For this, a large-scale experiment was conducted on the tidal flats of the Dutch Wadden Sea, by installing biodegradable artificial reefs along 630 m. Waves, sediment dynamics and sediment properties around the structures were monitored over three years. Our results demonstrate that intact structures attenuated circa 30% of the wave height with water levels below 0.5 m. Variability in wave-attenuation increased when the wind direction was parallel to the structures/foreshore. Sediment dynamics were variable due to the exposed nature of the location and environmental heterogeneity because of the landscape-scale set-up. We observed local sediment accretion up to 11 cm, however the effect did not expand beyond 10 m from the landward edge of the structures and up to 10 cm scouring was also found. Additionally, near sediment properties were not affected by the presence of the artificial reefs. Long-term effects could not be assessed due to the degradation of the structures during the experimental period. In general, we conclude that artificial reefs have the potential to attenuate waves and trap sediment on tidal flats. However, to benefit connected foreshore ecosystems like salt marshes, an even larger implementation scale and the use of more resistant structures in exposed sites is needed to affect long-term tidal flat morphology.

Coastal changes between the harbours of Castellón and Sagunto (Spain) from the mid-twentieth century to present

This paper analyses the coastal changes between the harbours of Castellón and Sagunto from 1956 until the present day. Images of the coastline in different years have been obtained from various sources (aerial photographs, satellite images, orthophotos) in order to estimate and compare the rates of shoreline advance and retreat. The results indicate a widespread tendency towards erosion due to human activity, which has limited the supply of sediments from source areas to the beaches. High rates of accretion are only recorded at places located upstream of the harbour: an advance of 230 m was recorded north of Burriana harbour, and one of up to 180 m to the north of Sagunto harbour. In contrast, retreats of more than 175 m were estimated in some sites along the study area. Hard engineering structures (groin fields, breakwaters) and artificial nourishment of beaches had a strong influence on the coastline’s behaviour from 1998 to 2018. Short-term coastal trend is erosive which is associated with storm events from January 2015 to December 2018.

Simulating dune evolution on managed coastlines: Exploring management options with the Coastal Recovery from Storms Tool (CReST)

Despite the importance of coastal dunes to many low-lying coastal communities and ecosystems, our understanding of how both climatic and anthropogenic pressures affect foredune evolution on time scales of years to decades is relatively poor. However, recently developed coupled numerical modeling tools have allowed for the exploration of the erosion and growth of coastal foredunes on time scales of hours to years. For example, Windsurf is a new process-based numerical modeling system (Cohn et al. 2019a) that simulates the evolution of dune-backed sandy coastal systems in response to wave, wind, and water level forcings. CReST, developed as a front-end interface to Windsurf, aims to add the ability to incorporate beach nourishment and dune construction, beach and dune grading, dune grass planting scenarios, dune grass removal, and the presence of hard engineering structures into the model framework to better account for the complex dynamics of managed coastlines. Initial model sensitivity tests suggest that the model provides a flexible framework to investigate the complex interactions between beaches and dunes for a variety of exploratory and applied applications.

The Influence of Climate Change on Coastal Erosion Vulnerability in Northeast Brazil

In this paper, an adapted methodology to evaluate coastal erosion vulnerability, which provides a basis for decision-making concerning risk management strategies, is described. The vulnerability evaluation was based on weighted indicators and assessed the vulnerability under different climate change scenarios. To generate the vulnerability index, dynamic processes, geo-indicators, and social and morphological parameters associated with modeled scenarios of sea level rise and predicted wave height changes were integrated. The study area included the sandy beaches in Pernambuco, NE Brazil, and was used to describe the practical application of this approach. Because the occupation of large sectors of the coastline was low, the vulnerability was concentrated in urbanized areas. The high-vulnerability sections of the coast were those with high population densities, high-rise buildings, induced coastal squeeze and hard engineering structures. The low-vulnerability beaches generally had low urbanization rates and well-conserved, resilient coastlines. Under future scenarios, the vulnerability of this coastal region will increase with sea level rise and wave height changes.

Maintaining a way of life for São Miguel Island (the Azores archipelago, Portugal): An assessment of coastal processes and protection

Traditional hard engineering structures and recently emerging soft engineering alternatives have been employed to protect vulnerable coastlines. Despite negative publicity, they have ensured community survival where socio-economic benefits outweigh adverse impacts. This is especially true for Small Islands (SI) where increasing sea levels and storm intensities threaten already limited land availability. This paper presents coastal vulnerability in São Miguel Island (the Azores SI archipelago) and considers SI issues with regard to coastal land loss. Regional wave statistics using 1998 to 2011 wind record showed: periods ranging from 7 to 13s (circa 83%); wave heights between 1 and 3m (circa 60%); and increasing trends in westerly (p=0.473), easterly (p=0.632) and southeasterly (p=0.932) waves. Sea level analyses between 1978 and 2007 indicated a statistically significant rising trend (2.5±0.4mmyr−1; p=0.000), while between 1996 and 2007 it was 3.3±1.5mmyr−1 (p=0.025), agreeing with other global sea level studies. Based on 2001 and 2008 population data and using zonal statistics, circa 60% of the Island's population was found to reside within 1km of the sea and the percentage of total population was linearly correlated with distance from the shoreline (r2=99%). Three case studies show hard coastal engineering solutions preserved Azorean coastal lifestyle and had little or no observed negative impacts on their environs. Although hard engineering is likely to remain a valuable and feasible coastal protection option, an inventory of São Miguel's population distribution, surf breaks, bathymetry and coastal erosion rates showed the potential of using multifunctional artificial reefs as a soft engineering solution. These offshore submerged breakwaters offer coastal protection while providing additional benefits such as surfing amenity and beach widening. Consequently, findings of this work can inform other SI communities.

20th century sediment budget trends on the Western Gulf of Lions shoreface (France): An application of an integrated method for the study of sediment coastal reservoirs

This paper presents a shoreface sediment budget established for the 20th century (1895–1984–2009) along the microtidal wave-dominated coast of the western Gulf of Lions (Languedoc-Roussillon, Mediterranean Sea, SE France). The implementation of a diachronic bathymetric approach, coupled with the definition of sand reservoirs (upper sand unit — USU) by very high-resolution seismic surveys and the results of LiDAR investigations, offers a new means of defining precisely the magnitude and change trends of the sediment budget. The aim of this study is to link the Large Scale Coastal Behaviour (LSCB) of the littoral prism (expressed in terms of shoreface sediment budget, shoreface sediment volume and spatial distribution pattern of cells) to climatic change, river sediment input to the coast, longshore sediment transport distribution, impact of hard coastal defence structures and artificial beach nourishment. The results show a significant reduction of the volume of the western Gulf of Lions littoral prism over 114years (−26.1±4.6×106m3). From 1895 to 1984, the overall budget is slightly positive, with a volume estimated at 4.1±3.5×106m3. For 1984–2009, however, the estimated sediment budgets clearly indicate that erosion is dominant over the last 25years, with a volume loss of −30.2±4.2×106m3. In relation to the long-term sediment budget and longshore drift pattern, the long-term trend of the USU volume distribution displays strong spatio-temporal contrasts linked to longshore sediment drift, spatial distribution of fluvial sediment inputs and hard engineering structures. Locally, the sedimentary reservoir is significantly eroded within a century (−80% of USU), since the initial amount present was low and not sustainable. The emphasis is on the importance of considering the volume changes of available sediment reservoirs rather than their losses and gains. Erosion of the Languedoc-Roussillon shoreface is likely to continue in the future due to the “natural” decrease of river sediment input and the sand removal for human purposes. Consequently the littoral sand prism results in sedimentary reservoirs that are gradually being used up.

Assessing sea level rise costs and adaptation benefits under uncertainty in Greece

Although sea-level rise (SLR) is not the only driver of coastal change, it is expected to radically alter the living conditions and prosperity of coastal communities in the decades to come. The economic assessment of sea level rise impacts and of coastal adaptation measures proves to be rather demanding due to the fact that these are complex phenomena, affected by both global conditions and local parameters. All these factors add to the uncertainty involved in climate change assessments, in general, and in SLR impacts in particular, creating significant ambiguity during the policy-making process. This paper wishes to contribute to existing literature by exploring modern management tools for assessing the economic impacts of SLR and the effectiveness of proactive coastal adaptation under uncertain conditions. To this end, first, the economic damages from long-term shoreline retreat and land inundation for scenarios of 0.5-m and 1-m SLR up to 2100 are estimated for the Greek coastal zone, both deterministically and probabilistically. The results indicate that probabilistic damages are lower than the deterministic ones by 6%, on average. However, the uncertainty results in a range of probable values, which are 45% lower and up to 40% higher than the deterministic estimates. Second, and most important, the application of real options valuation (ROV) in the economic assessment of adaptation measures is illustrated using four specific case sites. The findings show that ROV provides decision-makers with the flexibility to ‘adjust’ the so-called hard engineering structures to future SLR conditions by keeping all options (i.e. scale, deferral, acceleration or abandonment) open till further knowledge is gained. In this way, ROV creates an additional value that cannot be captured by ‘conventional’ valuation methods and, thus, it offers the potential to maximize long-term benefits for the society by making efficient use of fiscal resources for adaptation strategies.

Seeking harmony in coastal development for small islands: Exploring multifunctional artificial reefs for São Miguel Island, the Azores

The Azores is a remote archipelago rich in biodiversity, geodiversity and cultural heritage located in the middle of the North Atlantic Ocean. It comprises nine volcanic Small Islands (SIs) scattered over 600km and are vulnerable to coastal hazards due to limited land availability and ocean exposure. To mitigate and adapt to hazards and human occupation, traditional hard-engineering structures have been used. However, these structures have negative impacts on natural coastal character and amenity value and with growing environmental awareness, soft-engineering solutions designed to work with natural processes, such as multifunctional artificial reefs (MFARs), are globally becoming more appealing. MFARs are offshore submerged structures which provide coastal protection while enhancing marine and recreational amenities such as surfing, diving and beach widening. This paper determines “optimal” MFAR multifunctional design criteria based on current progress and assessment of nine international MFARs installed to-date. It subsequently explores MFAR feasibility in São Miguel Island, the biggest and most populated Azorean Island with the largest surfing population. An assessment of surf breaks was undertaken, including coastal processes and retreat rates, and MFAR site selection, criteria and rationale are discussed. By considering site-specific parameters such as local bathymetry, wave climate, tides, coastal processes and marine environment alongside tourism potential and surf culture, São Roque reef was selected as a potential MFAR to provide both coastal protection and surfing amenity.

Sedimentary processes on the NW Iberian Continental Shelf since the Little Ice Age

The OMEX core CD110 W90, retrieved from the Douro Mud Patch (DMP) off the River Douro in the north of Portugal, records the period since the beginning of Little Ice Age (LIA). The core chronology is based upon the data attributes for 210Pb, 137Cs and a 14C dating from a level near the core base. Geochemical, granulometric, microfaunal (benthic foraminifera) and compositional data suggest the occurrence of precipitation changes which may have been, at least partially, influenced by the North Atlantic Oscillation (NAO), that contributes to the regulation of the ocean–atmosphere dynamics in the North Atlantic.Southwesterly Atlantic storm track is associated with the negative phases of the NAO, when the Azores High is anomalously weak, higher oceanographic hydrodynamism, downwelling events and increased rainfall generally occurs. Prevalence of these characteristics during the LIA left a record that corresponds to phases of major floods. During these phases the DMP received a higher contribution of relatively coarse-grained terrigenous sediments, enriched in quartz particles, which diluted the contribution of other minerals, as indicated by reduced concentrations of several lithogenic chemical elements such as: Al, As, Ba, Ce, Co, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Ni, P, Rb, Sc, Sn, Th, V and Y. The presence of biogenic carbonate particles also underwent dilution, as revealed by the smaller abundance of foraminifera and correlative lower concentrations of Ca and Sr. During this period, the DMP also received an increased contribution of organic matter, indicated by higher values of lignin remains and a benthic foraminifera high productivity index, or BFHP, which gave rise to early diagenetic changes with pyrite formation. Since the beginning of the 20th century this contribution diminished, probably due to several drier periods and the impact of human activities in the river basins, e.g. construction of dams, or, on the littoral areas, construction of hard-engineering structures and sand extraction activities.During the first half of the 20th century mainly positive phases of the NAO prevailed, caused by the above normal strengthening of the subtropical high pressure centre of the Azores and the deepening of the low pressure centre in Iceland. These phases may have contributed to the reduction in the supply of both terrigenous sediments and organic matter from shallow water to the DMP. During the positive phases of the NAO, sedimentation became finer.The development of mining and industrial activities during the 20th century is marked, in this core, by higher concentrations of Pb. Furthermore, the erosion of heaps resulting from wolfram exploitation leaves its signature as a peak of W concentrations recorded in the sediments of the DMP deposited between the 1960s and the 1990s. Wolfram exploitation was an important activity in the middle part of the 20th century, particularly during the period of the Second World War.

Current countermeasure of beach erosion control and its application in Taiwan

The shoreline of Taiwan is approximately 1100 km long, composed of sandy beach, rocky coast, and reef coast. Almost half of the shoreline has been protected by seawalls, which play an important role for coastal protection and prevent people and infrastructure from coastal hazard. Besides, offshore breakwaters and groynes are also built in the serious erosion coastal shores. All these hard engineering structures made our coastal land safety to some extent at last fifty years. However, until now, the hard engineering structures applied for shore protection do not always work well on all the coasts around Taiwan. Some coastal areas still get eroded seriously with structures being damaged. Furthermore in the recent years, people gradually value the shore protection from different viewpoints, like environment, recreation, and ecology. The objectives of the shore protection are diversified by these new demands. Therefore, the purpose of this study is to evaluate the strategy on how to conjoint soft solutions into the current hard engineering structures for beach erosion control throughout Taiwan coast. Meanwhile, this paper will also introduce environmentally, user-oriented, and technically sound creditable protection works to meet the new trends of shore protection. For application purpose, two local sites in the southwestern Taiwan coast are selected for field experimental study to integrate the proposed soft solution with hard shore protection system at present. Furthermore for coastal management purpose, this paper also collects and analyzes hydro-morphodynamic data around Taiwan in order to identify beach erosion mechanism. Lastly, the results are presented by database and geographic information system.

Connecting large-scale coastal behaviour with coastal management of the Rhône delta

The aim of this paper is to connect the Large Scale Coastal Behaviour (LSCB) of the Rhône delta (shoreface sediment budget, river sediment input to the beaches, climatic change) with the impact and efficiency of hard engineering coastal structures. The analysis of the 1895 to 1974 bathymetric maps as well as 2D modelling of the effect of wave blocking on longshore transport allows us to draw up a conceptual model of the LSCB of the Rhône delta. The river sand input, settled in the mouth area (prodeltaic lobe), favours the advance of adjacent beaches. There is however a very weak alongshore sand feeding of the non-adjacent beaches farther off the mouth. After a mouth shift, the prodelta is eroded by aggressive waves and the sand is moved alongshore to build spits. This conceptual model suggests that there is a “timeshift” between the input of river sediments to the sea and the build up of a beach (nonadjacent to the mouth). Nowadays, as the river channels are controlled by dykes and human interventions, a river shift is not possible. It thus appears unlikely that the river sediments can supply the beaches of the Rhône delta coast. Under these conditions, we must expect that the problems of erosion will continue at Saintes-Maries-de-la-Mer and on the Faraman shore, in areas with chronic erosion where the shoreline retreat has been partially stopped by hard engineering practices in the 1980s. Therefore, these artificially stabilised sectors remain potentially under threat because of profile steepening and downdrift erosion evidenced in this paper by bathymetric profile measurements. In the long-term (1905 to 2003), the temporal analysis of the storm surges and the sea level show very weak but reliable increasing trends. Thus, these climatic agents will be more aggressive on the beaches and on the coastal structures calling their efficiency into question. We also evidence that the hard engineering structures were built in a favourable climatic context during the 1980s meanwhile the storm surges and the sea-level rise are stronger since the 1990s. Regarding to the LSCB of the Rhône delta, and the impact of hard engineering coastal structures, we suggest that classical hard coastal protections are not the best option to protect the coast.

Flood-plain management program in Rapid City, South Dakota

Research Article| July 01, 1984 Flood-plain management program in Rapid City, South Dakota PERRY H. RAHN PERRY H. RAHN 1Department of Geology and Geological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota 57701 Search for other works by this author on: GSW Google Scholar Author and Article Information PERRY H. RAHN 1Department of Geology and Geological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota 57701 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1984) 95 (7): 838–843. https://doi.org/10.1130/0016-7606(1984)95<838:FMPIRC>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation PERRY H. RAHN; Flood-plain management program in Rapid City, South Dakota. GSA Bulletin 1984;; 95 (7): 838–843. doi: https://doi.org/10.1130/0016-7606(1984)95<838:FMPIRC>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Following the devastating flood of June 9, 1972, Rapid City, South Dakota, embarked on a flood-plain management program. A “flood-way” was delineated and all homes and motels, as well as most commercial establishments, were removed from the floodway. Almost the entire area inundated by the 1972 flood is now a beautiful park, illustrating that man can live in harmony with natural processes without spending vast sums of money for hard engineering structures such as dams or levees.From a national perspective, it is desirable to reserve flood plains for agricultural use. Unfortunately, many flood plains are being urbanized, which not only takes agricultural land out of production, but also gives impetus to dam construction that results in the inundation of more land. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.