Beach Nourishment Research Articles

A remote monitoring approach for coastal engineering projects

High costs and project-based (short-term) financing mean that coastal engineering projects are often undertaken in the absence of appropriate post-construction monitoring programmes. Consequently, the performance of shoreline-stabilizing structures or beach nourishments cannot be properly quantified. Given the high value of beaches and the increase in erosion problems and coastal engineering responses, managers require as much accurate data as possible to support efficient decision-making. This work presents a methodological approach to characterise coastline position changes as a result of engineering actions. We describe a new, low-cost method based on satellite remote sensing to monitor shoreline evolution at high temporal and spatial resolution pre-, during and post-implementation. Initially, satellite-derived waterlines are identified and extracted from publicly available satellite imagery of the Landsat 5, 7, 8, and 9, and Sentinel-2 constellations using the automatic shoreline extraction tool SHOREX. The waterline positions are then compiled, differences over time are quantified, and a matrix is constructed that allows easy depiction and interpretation of spatial and temporal patterns of erosion/accretion. This allows the access and the comprehension of the morphological data by the non-expert. Two examples of application on the Valencian coast of Spain at different spatial scales demonstrate how beach response to coastal engineering actions can be characterised at different levels of detail (from local to regional) and over different periods of time. These applications evidence the utility of the approach as it allows analysis of pre- and post-intervention coastal change and offers a means to overcome the widespread lack of monitoring and hence to improve coastal engineering practice.

When “More” Is “Too Much”—A Study on Tourists’ Perception Regarding Beach Restoration in Mamaia on the Romanian Black Sea Coast

When “More” Is “Too Much”—A Study on Tourists’ Perception Regarding Beach Restoration in Mamaia on the Romanian Black Sea Coast

Can microplastic pollution be affected by beach nourishment? Assessment in intertidal sediment and bivalves.

Several methods can be used to mitigate coastal erosion, and one of the leading solutions is known as beach nourishment (BN), which involves using dredged material for nourishment, adding sand to extend an eroding beach. Although it has many advantages, the environmental impacts of BN remain poorly understood, especially on plastic pollution, which had not been investigated until this study. We aimed to compare the abundance and distribution of microplastics (MPs) found in intertidal sediments and specimens of the bivalve mollusks Crassostrea brasiliana, Mytella strigata, Perna perna, and Tivela mactroides, collected in two beaches of Vitoria, Southeast of Brazil (da Costa et al., 2023), immediately after a BN process. We collected three replicates of intertidal sediment samples at each one of the five sampling points and 20 individuals of each species at two sampling points. This study found 9057 microplastics, of which 1960 were present in the sediment samples and 7097 in the set of bivalves analyzed, giving a frequency of occurrence of 100%. The results show an increase of 171% in the total number of MPs analyzed after the BN process. This significant increase in MPs after the BN indicates that this type of action can lead to a drastic increase in the MPs available in the local marine environment, further increasing the risk of contamination of the regional biota.

Beach nourishment with coarse sediments: An in-situ investigation on the issues of abrasion and chipping

Beach nourishment with coarse sediments: An in-situ investigation on the issues of abrasion and chipping

Influence mechanisms of the submerged sand engine on coastal protection as the extension of beach nourishment

As an innovative practice of beach nourishment, a submerged sand engine was constructed for coastal restoration in Jinsha Bay, China. The submerged sand engine is composed of a nourished beach, submerged sand groins and submerged sandbars. To investigate hydrodynamic and geomorphological responses to the system, a multi-coupled model is established for numerical simulations. The numerical results indicate that the submerged sand engine serves structural functions in wave attenuation and flow regulation. The system reduces significant wave heights of storm waves by 79% at most, and mitigates alongshore current speed in embayed areas by a 10% decrease in the embayed area. In a typical typhoon event, the system reduces erosion spots with erosion depth over 0.09 m by 100% along embayed beaches. Moreover, submerged sandbars serve similar contributions on cross-shore and alongshore sediment supplements, while alongshore contributions of submerged sand groins are over 75%. Hence the cross-shore profiles generally present shoreward movement of submerged sandbars and head scour of submerged sand groins. Furthermore, the submerged sand engine saves 90% expenses of the Sand Engine in terms of the sand volume cost per unit length of the target shore. The submerged sand engine is of flexible and economic advantages in coastal protection.

Impacts of an Artificial Sandbar on Wave Transformation and Runup over a Nourished Beach

Due to increasing coastal flooding and erosion in changing climate and rising sea level, there is a growing need for coastal protection and ecological restoration. Artificial sandbars have become popular green coastal infrastructure to protect coasts from these natural hazards. To assess the effect of an artificial sandbar on wave transformation over a beach under normal and storm wave conditions, a high-resolution non-hydrostatic model based on XBeach is established at the laboratory scale. Under normal wave conditions, wave energy is mainly concentrated in short wave frequency bands. The wave setup is negligible on the shoreface but becomes more significant over the beach face, and wave nonlinearity increases with decreasing water depth. The artificial sandbar reduces the wave setup by 22% and causes considerable changes in wave skewness, wave asymmetry, and flow velocity. Under storm wave conditions, as the incident wave height increases, the wave energy in the long wave frequency bands rises, while it decreases in the short wave frequency bands. The wave dissipation coefficient of an artificial sandbar increases first and then decreases with increasing incident wave height, and the opposite is true with the transmission coefficient. It features that the effect of an artificial sandbar on wave energy dissipation strengthens first and then weakens with increasing incident wave height. Additionally, an empirical formula for the wave runup was proposed based on the model results of the wave runup for storm wave conditions. The study reveals the complex processes of wave–structure–coast interactions and provides scientific evidence for the design of an artificial sandbar in beach nourishment projects.

Balancing between natural development and human intervention

The paper discusses over 10 years of experience (2009–2021) with dune development in a newly constructed coastal area in The Netherlands. The area (ca. 40 ha) was constructed by foreshore and beach nourishment and meant to compensate expected damage to existing dune vegetation, caused by nearby harbour extension and associated industrial activities. The development of the new dune was done applying the principles of ‘Building with Nature’, with as little human interference as possible. However, in the course of time several management measures were necessary to steer the vegetation succession in the right direction of the compensation targets. Dune development in natural aeolian coastal dunes differs from that in dunes built up from sea bottom sand. Before the compensation project there was little experience on how nourished marine sediments would affect the processes of sand transport, groundwater dynamics and vegetation development. After 10 years of development, the succession to the compensation targets is on its way. The project monitoring gave insights in the development of constructed dunes and in balancing between natural development and human intervention.

Beach nourishment response and recent morphological evolution of Minnesota Point, Lake Superior

Beach nourishments are a popular nature-based alternative to armoring for shoreline erosion mitigation, but nourishments have been criticized due to their environmental impacts and uncertain sustainability. Monitoring is often nonexistent or insufficient to constrain nourishment longevity and inform the renourishment interval required to maintain shoreline protection. This study uses a combination of topobathymetric surveys, high-resolution satellite-derived shorelines, and coastal engineering analyses to investigate the recent evolution of Minnesota Point and the fate of three beach nourishments constructed adjacent to littoral barriers. We use semi-empirical formulations for sediment compatibility, wave runup, and longshore sediment transport to inform the observed nourishment behavior. Minnesota Point experienced widespread foredune retreat averaging 7±2.8 m from 2009–2019 and 130,000 (70,000–140,000) m3 of sediment was eroded during this interval. The 2019 nourishment at the Superior Entry was rapidly eroded by strong storms, losing >80% of the added beach width by the following spring. The 2020 and 2021 nourishments at the Duluth Entry retained >80% of the nourishment material at the time of the last topobathymetric survey in the fall of 2022, and satellite-derived shorelines indicate that the beach remained 10 m wider than pre-nourishment conditions at the end of 2023. Modeled longshore transport rates over the period 2009–2022 averaged 11,400 m3 yr−1 northwestward at the Superior Entry, nearly 3x greater than the 4000 m3 yr−1 southeastward transport modeled at the Duluth Entry. These observations show that differences in shoreline orientation, littoral sediment supply, and grain size compatibility can lead to contrasting beach nourishment longevities, and this study provides additional measurements of Minnesota Point’s long-term morphological change which can help inform coastal resiliency efforts.

Evolution of the beach artificial nourishments in the Tomis North sector, a short term analysis (2013-2024)

The Romanian coastline is part of the western coast of the Black Sea, extending for about 245 km, morphologically divided into two units: the northern unit, from Musura Bay to Cape Midia, with deltaic and lagoon origin, and the southern unit, from Cape Midia to Vama Veche, characterised by well-developed cliffs and wide beaches. This last coastal sector includes both accumulating coastlines (beaches) and anthropogenic features (ports and breakwaters). Constanta, the largest and most important city in Dobrogea, claims a rich history and a variety of tourist attractions, with its beaches stretching some 6 km along the coast from Tomis Marina to the entrance of Mamaia Resort. This study analyses the recent changes observed at a popular tourist beach known as Reyna Beach, located near Mamaia Resort, following the nourishment works carried out in the framework of the "Protection and Rehabilitation of the Southern Part of the Romanian Black Sea Coast" project. The project involved extensive hydrogeographic works, including the rehabilitation of piers, the construction of submerged breakwaters and beach nourishment. This paper aims to analyse the evolution of the coastal area from a geographical perspective, including geological and geomorphological characteristics, using various data sources such as satellite images, field measurements and previous maps associated to grounding studies.

Mechanical properties and restoring force model of Squeezing Rub-type Particle Damper

The sliding effect of isolation bearings has been proven to effectively mitigate the seismic effects on large-span bridges. However, it also results in excessive relative displacement between the main girder and piers during earthquakes. In this study, a pioneering Squeezing Rub-type Particle Damper (SRPD) is developed to address this issue. In order to verify the damping characteristics of SRPDs and investigate the working principle of squeezing friction energy dissipation, five quasi-static tests were conducted on SRPDs using two particle damping materials with different compactness levels. In order to compare the energy dissipation performance, comparative tests were conducted on Non-Squeezing-type Particle Dampers (NSPDs) and SRPDs. Utilizing regression analysis, two skeletal curve models for SRPDs were proposed, alongside a detailed restoring force model that incorporates considerations for both the pinching effect and stiffness degradation phenomena observed during the loading and unloading phases. The experimental results demonstrate that the maximum damping force of SRPDs can reach 16 times that of NSPDs, and the energy dissipation of each loading cycle can reach 21.06 times that of NSPDs. SRPDs exhibits improved energy dissipation performance when using high-density blended quartz sand. After sand replenishment repairs,damping force and energy dissipation per cycle of SRPDs were significantly enhanced. The proposed restoring force models of SRPDs aligns well with the experimental curves, underscoring its efficacy in accurately characterizing the hysteresis performance of SRPDs.

Effects of nourished beach morphology on storm response

AbstractField observations on storm induced beach changes are important to improve our effort on beach management. This study compared storm induced beach changes caused by hurricane Hermine in 2016 (4 years after a beach nourishment) and Tropical Storm Eta in 2020 (2 years after a beach renourishment) along the barrier-island coast of west-central Florida. Pre-Eta beach were 1 to 2 times wider than that of pre-Hermine. Since Hurricane Hermine and TS Eta generated a similar hydrodynamic condition for the study site, comparing beach changes induced by these two storms provides a unique opportunity to investigate the response of different antecedent beach conditions to energetic events. The shore protection effect of beach nourishment is apparently evidenced by the fact that post-Eta shoreline was located seaward of those post-Hermine at half of the beach-profile locations in the study area. The shore protection effect in the subaerial portion of the beach, however, is not obvious for the other half of beach profiles where shoreline positions were retreated to similar locations after these two storms. Instead, their shore protection effect occurred in the sub-aqueous portion of the beach and was indicated by higher sandbar crests located closer to the shoreline, which can dissipate and reduce incoming wave energy. The shoreline elevation needs to be properly defined (Mean High Water vs Mean Low Water line) as it is used as a proxy to represent beach volume loss. For Hermine induced beach change, no significant correlation exists between MHW line change and beach volume loss. While a significant correlation exists between MHW line change and beach volume loss induced by TS Eta. This correlation pattern switched if the shoreline here is defined as mean low water line. For efficient beach/shoreline management, multiple proxies (e.g., sandbar height and location of its crest and trough) in addition to shoreline change should be used to assess the performance of beach nourishment project.

Beach nourishment for coastal aquifersimpacted by climate change and population growth using machine learning approaches

Groundwater in coastal regions is threatened by saltwater intrusion (SWI). Beach nourishment is used in this study to manage SWI in the Biscayne aquifer, Florida, USA, using a 3D SEAWAT model nourishment considering the future sea level rise and freshwater over-pumping. The present study focused on the development and comparative evaluation of seven machine learning (ML) models, i.e., additive regression (AR), support vector machine (SVM), reduced error pruning tree (REPTree), Bagging, random subspace (RSS), random forest (RF), artificial neural network (ANN) to predict the SWI using beach nourishment. The performance of ML models was assessed using statistical indicators such as coefficient of determination (R2), Nash–Sutcliffe efficiency (NSE), means absolute error (MAE), root mean square error (RMSE), and root relative squared error (RRSE) along with the graphical inspection (i.e., Radar and Taylor diagram). The findings indicate that applying SVM, Bagging, RSS, and RF models has great potential in predicting the SWI values with limited data in the study area. The RF model emerged as the best fit and closely matched observed values; it obtained R2 (0.999), NSE (0.999), MAE (0.324), RRSE (0.209), and RMSE (0.416) during the testing process. The present study concludes that the RF model could be a valuable tool for accurate predictions of SWI and effective water management in coastal areas.

Addressing the climate adaptation tracking gap: an assessment method and its application to the Caribbean region

This article addresses the climate adaptation tracking gap. Indeed, we still ignore the intensity, nature, spatial distribution, effectiveness, and recent evolution of adaptation efforts at the national, regional, and global scales. We propose a web-based replicable assessment method using key variables to document adaptation efforts: country/territory, location, goal, implementation date, type of action, holder, funding source. Applying it to the Caribbean region, we analyzed 100 coastal adaptation actions. This studies the method while also highlighting the difficulties faced to track adaptation. We found that coastal adaptation efforts are substantial and increasing in the Caribbean, revealing the use of diversified adaptation actions; prevalence of hard protection (51%); increase use of Nature-based Solutions (22%); limited use of retreat (6%); and accommodation (2%). Combined actions (17%) increased over time, due to the failure of single actions and need to find tradeoffs between human asset protection encouraging hard protection and the maintenance of attractive tourist beaches encouraging beach nourishment. Puerto Rico and Trinidad and Tobago fall under the engineering-based “one-size-fits-all” adaptation model, whereas Jamaica and Barbados experiment diversified options and combinations of options. Jamaica, Puerto Rico, Trinidad and Tobago, and Barbados are particularly active in taking adaptation action, while most dependent islands and sub-national island jurisdictions have no adaptation action reported. Considering the advantages and limitations of a web-based method compared to a field-based approach, we recommend the combined use of these two complementary approaches to support adaptation tracking and help structuring communities of practice to the benefits of decision-makers and practitioners and scholars.

Surf zone hazards before and after a beach nourishment in Virginia, USA

Beach nourishment is the leading coastal protection technique in the United States to combat erosion, enhance resilience to storm surge, and maintain recreational value. Despite these benefits, anecdotal reports suggest that beach nourishments elevate the surf zone hazard to beach patrons by steepening the beach face and altering the shoreface morphology such that conditions are more favorable for rip current formation. This study analyzes lifeguard rescue reports collected on the United States Atlantic Coast before and after a 2019 beach nourishment in Virginia Beach, Virginia, to assess whether the nourishment was correlated with an increased hazard to beach patrons. The data indicate that regardless of nourishment status, rescues were most probable during periods of high rip current probability (moderate to large wave heights and low-obliquity wave angles), along with low water level. To formally quantify pre-versus post-nourishment hazards, the proportion of rescues observed in nourished versus unnourished beach zones was compared with bootstrapped distributions of the pre-nourishment rescue proportions. Although the proportion of rescues in the nourished section of the beach exceeds the pre-nourishment average, it is not outside the overall range of pre-nourishment values obtained by random resampling. Consequently, there is insufficient evidence to conclude that the existing coastal management beach nourishment strategy increased the hazard to beach patrons at Virginia Beach.

Narrating of collaborative governance in Sejarah Beach restoration, Batu Bara Regency, Indonesia

This article examines the collaborative governance strategy implemented by the Batu Bara Regency Government in restoring Sejarah Beach. Beaches are critical assets that represent the identity of a region, provide economic benefits, and support the surrounding environmental ecosystem. Unfortunately, many beaches experience environmental degradation and other socio-economic problems. Pantai Sejarah in Batu Bara Regency is no exception, which faces issues such as prostitution, environmental degradation, and local poverty. Using a qualitative methodology, this research explores the collaborative approach used in the revitalization of Pantai Sejarah. In-depth interviews were conducted with various key stakeholders, including representatives from local government agencies (Environmental Agency, Forestry Agency, and Regional Development Agency), PT Inalum's HR management, and local community members. The findings of this study show that the implementation of the collaborative governance approach by the local government has transformed Sejarah Beach into an integrated tourist attraction. In addition, this collaborative initiative also created economic opportunities, including small businesses, new jobs, and revenue for the government. The collaborative effort also addresses social issues such as prostitution through coordinated action between law enforcement, government, and the local community. Furthermore, the collaborative governance approach provides a comprehensive solution to coastal area management by addressing social challenges alongside environmental conservation and economic development.

Beach Nourishment Protection against Storms for Contrasting Backshore Typologies

The protection against a storm event provided by nourishment to Costa da Caparica beaches near Lisbon, Portugal, is investigated numerically with a two-dimensional-horizontal morphodynamic model able to generate and propagate the longer infragravity waves. The beach has a groyne field and a multi-typology backshore. The nourishment of 106 m3 of sand was placed at the beach face and backshore. Pre- and post-nourishment topo-bathymetric surveys of the beach, which suffers from chronic erosion, were performed under a monitoring program. The morphodynamics of the pre- and post-nourished beach when exposed to a simulated historically damaging storm event and the post-storm morphologies were compared to evaluate the efficacy of the nourishment. Results indicate that the lower surface level of the beach face and backshore of the pre-nourished beach induces a larger erosion volume. The nourishment prevented the extreme retreat of the shoreline that occurred during the storm in the pre-nourished beach and reduced the storm-induced erosion volume by 20%, thus protecting the beach effectively against the storm. The beach backshore typology (seawall vs. dune) exerts differential influences on the sandy bottom. As a result, multi-typology backshores induce alongshore variability in cross-shore dynamics. The backshore seawalls exposed to direct wave action cause higher erosion volumes and a larger cross-shore extension of the active zone. The most vulnerable alongshore sectors of the beach were identified and related to the mechanisms responsible for the erosion phenomenon. These findings strengthen the importance of sand nourishment for the protection and sustainability of beaches, particularly those with a seawall at the backshore, where storm events cause higher erosion.

Changes in Loggerhead Sea Turtle Nesting Behavior on a Nourished Beach in Southeast Florida

Changes in Loggerhead Sea Turtle Nesting Behavior on a Nourished Beach in Southeast Florida

The recreational and economic value of Florida beaches

Florida is the world’s top travel destination and. if it were its own country, it would have more tourist visits than any other country. Its sandy beaches extend a shoreline length almost as great as the combined lengths of sandy beaches in California, Texas, and North Carolina. Florida’s beaches are easily America’s recreational playground. Every year, Florida beaches attract approximately 70% more day visits than combined attendance at national parks, college and professional sports, amusement parks, cruises, and NASCAR events. Beach tourism plays a huge role in Florida’s economy. Manufacturing and residential construction are major industries in Florida, but their revenues are each a fraction of beach-oriented tourist spending. Florida’s farmland, ranches, and forests cover 75% of its land area, but beach-oriented tourist spending is more than 10 times the total receipts of all Florida agriculture and forestry. Beach-oriented tourists generate $23.3 billion in tax revenues annually. These tax revenues are more than double the combined salaries of Florida K-12 public school teachers, law enforcement officers, and instructors at colleges and universities. Some Florida beaches have sand deficits because dams on rivers have blocked sand that normally would flow to the coast, and navigation projects have diverted sand out of the littoral system to ebb and flood shoals. Beach nourishment has then been needed to restore and maintain the beaches. Beaches widened by nourishment have not only been a magnet for tourists, but have also protected bil- lions of dollars of shore infrastructure from hurricanes. Beach nourishment has been a bargain, with beach-oriented tourists in Florida generating six times more tax revenues each year than have been spent on Florida beach nourishment during the 80 years from 1944-2023 (in 2022 dollars to account for inflation). Most Florida beach nourishment has been placed in the past 50 years, and beach-oriented tourists have generated $310 dollars in tax revenues and $1070 in Gross Domestic Product (GDP) annually for every $1 spent on beach nourishment. Miami Beach is a good example of the economic benefits of beach nourishment. It had almost no beach in the mid-1970s because of erosion, causing tourism to drop rapidly and itself to become a “seedy backwater of debt-ridden hotels.” Beach nourishment starting in 1978 caused a boom in tourism, and today Miami Beach has the most valuable property in Florida — worth more than the value of all Florida cropland. Miami Beach has had a return of $550 in tourist-generated taxes and $3900 in GDP for every $1 spent on beach nourishment.

Influence of structure characteristics on wave transmission and shoreline response at a low-crested segmented breakwater in Little Egg Harbor Township, NJ

Graveling Point Beach, a public beach within Little Egg Harbor Township, New Jer- sey, has been experiencing long-term erosion. To address the issue, a living shoreline project consisting of four low-crested rubble-mound breakwaters and a beach nour- ishment was constructed beginning in fall 2022 (structures) and finishing in spring 2023 (beach nourishment). A variety of field methods were used to investigate the influence of the breakwater system on wave transmission and beach fill evolution. The observations are then compared to common empirical estimations. A median wave transmission coefficient of 0.4 was measured for incident waves with a median height and peak period of 9 cm and 2 sec, respectively. The observed transmission coefficient was higher than that predicted by models such as Briganti et al. (2003) and Van der Meer and Daemen (1994) suggesting other processes such as diffraction may be influencing the results. Structure from Motion (SfM) was used to generate a series of Digital Elevation Models (DEMs) which show salients forming behind the structures. The resulting salient growth was compared to the model of Suh and Dalrymple (1987), which was shown to overpredict the amplitude of the salient at Graveling Point. However, the expected relationship of breakwaters with increased offshore distance having shorter salient lengths was generally observed. The equation was refit using the field data at Graveling Point and laboratory data with similar wave heights and periods from Suh and Dalrymple to derive a modified model that may be more appropriate in low-energy environments

Evaluation of beach nourishment in Mar del plata, Argentina: An application of the CoastSat toolkit

Sandy coasts play a crucial role in various human activities and support the economies of many coastal states. Due to their importance, coastal erosion mitigation techniques are often implemented. Among these techniques, beach nourishment is considered an environmentally acceptable method for coastal protection and restoration. In this work, a methodology for the evaluation of such projects is proposed and applied to the biggest beach nourishment project in the city of Mar del Plata, Argentina. The nourishment was carried out between 1998 and 1999 in Playa Grande (PG), Varese (V) and Bristol (B) bays. The CoastSat toolkit was implemented to obtain shoreline positions from satellite imagery and to derive a 36-year monthly time series of beach width in the region. For the analysis, three distinctives time lapses are identified: pre-intervention, response, and new equilibrium. An exponential decay function was fitted to determine the response lapse and its characteristics. Metrics such as mean beach width and trends were computed and used to compare the condition of beaches before and after the project. Results show that the region experienced a net growth after nourishment, with beach width doubling in Bristol and Playa Grande, and increasing tenfold in Varase. Nourishment did not alter the erosive trends of Playa Grande and Bristol, nor the growth trend of Varese. Regarding renourishment planning, according to our findings, for Playa Grande and Bristol beaches to achieve a net growth of 1 m, it would require the deposition of 17 m³ of sediment per meter of coastline. This study highlights the suitability of the CoastSat toolkit for assessing the effectiveness of beach regeneration.