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The northern sector of Waihi Beach is an example of chronic erosive tendency. The sediment deficit along the area of beach fronting the seawall means that there is often no beach at high tide. This existing situation, and the various remedial options suggested, has created an emotive issue for beach residents. Accordingly, the current study was undertaken to identify and evaluate the fundamental coastal processes impacting upon the erosion at northern Waihi Beach. Methods used to investigate this problem included: beach profiling and shallow water hydrographic surveying; mapping of sediments and the distribution of bedforms on the inner shelf using side-scan sonar, identification of nearshore sediment transport pathways from sediment textural analyses; collection and analysis of nearshore wave and current data; and numerical modelling of wave refraction and sediment transport processes. A side-scan sonar survey, ground-truthed by surficial sediment analyses and underwater video and diver observations, indicated that the shallow inshore zone is characterised by a relatively featureless seabed dominated by fine sands. Large shore-normal sand ridges (η=0.4-2.5 m, λ=300-1400), with crests oriented northeast to southwest were identified between 15-30 m water depth offshore northern Waihi Beach. These very pronounced features consist of coarse megarippled (η≈0.12 m, λ≈1 m) sediment. Sediment textural analyses revealed that offshore sediments vary from fine to coarse sand, showing a seaward-coarsening progression. Beach sediments consist of predominantly fine sands, with a slight inferred fining in grain size that occurs towards the northern end of the beach. This is possibly a result of lower wave energy when subject to swell and sea waves from the north, due to sheltering in the lee of Rapitiotio Point. 80 days of wave and current data were collected offshore northern Waihi Beach, during two separate deployments in Nov/Dec 2007 and May/June 2008. The summer deployment was characterised by waves from a northeast-east origin (Hs=1.09m; Ts=7.13s). Similar conditions were exhibited during the winter deployment (Hs=0.95m; Ts=6.79s). Observed relationships between wind direction and near-bed current direction, combined with calculated sediment entrainment rates, enabled predictions of the frequency of shoreward sediment transport by bottom currents to be made. Onshore currents, associated with winds from the southwest, prevailed during the deployment period. However, observed current velocities alone were generally incapable of inducing sediment motion. Analysis suggests that wave properties are likely to govern the frequency of sediment transport in the nearshore, as their presence is required to lift sediment into suspension for dispersal by ambient background currents. Onshore movement of sediment was estimated to be ~11,800 m3/year or 2.6 m3/m. Monochromatic wave statistics measured during the field study were used to calibrate a numerical wave refraction model. The wave refraction influence of Mayor Island was found to be the major feature influencing the distribution of wave energy along the shoreline, which is likely to contribute to localised accelerated beach erosion and dune setback. Wave energy focusing at northern Waihi Beach is maximised by swell waves, resulting in greater wave heights along eroding sectors of the beach. Potential sediment transport rates were investigated. Results suggest the littoral drift direction was bi-directional at northern Waihi Beach, although net littoral drift was southeasterly during the study period. An estimated net loss of 46,200 m3/year or 10.3 m3/m was predicted for northern Waihi Beach during the present study. Longer-term drift patterns were examined using a five year record of wave data collected offshore Pukehina by Environment Bay or Plenty from 2003-2008. Similar patterns but with lower magnitudes of sediment transport were obtained, with net annual drift rates estimated to range from 1,300-58,000 m3/year. A conceptual model of nearshore sediment dynamics is proposed for Waihi Beach to identify the major factors contributing to long-term erosion in the northern sector. Approximately 115,000 m3 of sediment was estimated to be moving within the defined northern Waihi Beach littoral cell during the study period. The derived sediment budget produced a net deficit of sediment of approximately 36,000 m3/year or -8 m3/year during the year commencing November 2007. The net southeasterly littoral drift was determined the major contributor to the net erosion rate during the study period, with alongshore transport rates exceeding available supply to the beach from diabathic movement of sediment onshore. Several aspects of the erosion problem at northern Waihi Beach are recommended to be researched further to identify what coastal management options are required.

This research undertakes to examine factors that contribute to make Australian national and cultural identity: shared history, narratives symbols, icons, places and memories that are united by a single political and geographical boundary. In particular, it considers the role of place on Australian national and cultural identity. This is a timely exercise since 'Australianess' is increasingly cited as a factor in federal government policy development. In order to address such a broad and complex area, the agenda has been limited to three specific locations: the beach, the verandah and the backyard. These sites have been selected first because of their prominent iconic status within the notion of 'Australianess' and, second, because of the underlying functional parallels that unite them. The present thesis contends that, unlike the function-specific sites where identity is neutralised by globalised standards of appearance, behaviour and harsh fluorescent light, the beach, the verandah and the backyard are ambiguous zones of in between that provide escape, shelter as well as spiritual sanctuary. The figures engage with the nominated locations in accordance with the significance, the meanings that they ascribe to that particular site. These meanings, however, vary greatly from person to person and from demographic to demographic, hence, the grasp of a universally binding sense of identity becomes a slippery proposition. National and cultural seity - the way we are and the way we perceive ourselves as a unified collective - is conditional to a number of factors, the most enduring and pervasive of these is the sense of place, the landscape, the way we affect it and, reciprocally, the way it affects us. National and cultural identity is never static, but remains in a state of perpetual evolution. It must be continually re-assessed in order to remain abreast of the cultural palimpsest as successive waves and generations of people from a variety of backgrounds, situations, ideas and forms of expression inscribe notions of self into their immediate environment.

Thesis (M.C.E.)--University of Delaware, 2007. / Principal faculty advisor: Nobuhisa Kobayashi, Dept. of Civil & Environmental Engineering. Includes bibliographical references.

Excess sedimentation began affecting the wetland dynamics of Pine Gully in Seabrook, Texas during the first quarter of 2004. This sedimentation was sudden and became a serious problem for the dynamics of the Pine Gully wetland because the fine, well sorted, quartz rich sediments began plugging the main channel of the previously tidally dominated wetland. Progressive sedimentation has produced overbank deposits in the marine grasses, contributing to the death of wetland grasses by sediment chocking. The main purpose of this study is to determine the new source and mechanism of sedimentation in Pine Gully, document changes from sedimentation, and determine a solution to prevent future sedimentation. Sedimentation in Pine Gully and coastal areas adjacent to Pine Gully has occurred in a region that has experienced subsidence and sea level rise. The sedimentation in Pine Gully is a direct result of new and sustained sediment at the mouth of Pine Gully. These new sediments are transported into Pine Gully by displacement waves from ships moving through the Houston Ship Channel. Beach renourishment at Wright Beach, located a half mile north of Pine Gully, occurred as Pine Gully experienced sedimentation. Construction of a breakwater at the mouth of Pine Gully and subsequent removal of sediment in Pine Gully itself is ultimately the solution to revitalizing the wetland to its pre-sedimentation state. Replanting of native vegetation killed off by sedimentation is recommended and would hasten the recovery of the wetland. Documenting the effects of this unique sedimentation in Pine Gully has implications for the future. Beach renourishment or coastal projects that may contribute excess sediment to the coastline should be concerned with unintended effects they may cause. Although an historically eroding shoreline exists, the effects of excess sedimentation can be severe. A coastal study should be done before sediment is added to the shoreline to identify any areas within the sphere of influence of the project. Ecosystems determined to be within the sphere of influence by a coastal study should implement preventative measures at those locations to avoid an ecological disaster similar to that in Pine Gully.

Erosion problems are not only in the Texas area, but exist also along the coastline all over the world. Even though many researchers have studied coastal processes related with beach erosion and deposition over the decades, these processes are too complex to understand completely and field measurements are difficult to obtain during landfall of storms which cause fatal damages. Overwash is strongly suspected to cause extreme erosion as seen from long-term field measurements in the upper Texas coast. Overwash and washover are the source of cross-shore erosion and deposition of beach material along the coast, respectively. Waves superimposed on increased storm surges overtop and generate serious erosion of the berm. However, the data for these processes do not completely describe the shoreline erosion problems. Providing better descriptions requires field measurements and laboratory experiments with careful calibration. This study was conducted in two major sections. First was a field measurement and second was a laboratory experiment. This study used the RTK-DGPS to measure the change in the beach profile over multi year period. The GPS system is one of the ways to have the best resolution. The laboratory experiment was done in a 2D wave tank on mid-scale based on similitude law at Texas A&M University. The experiment was necessary to obtain better empirical formulas. The erosion rate of the sand was measured at different wave conditions and slopes of the berm or upper beach face in regular and irregular waves respectively. The erosion rate is much bigger at higher wave height, longer wave period and steeper beach face. The erosion rate is increased proportional to speed of bore and it is decreased with time. The empirical formulas were the first approach to simulate the impact of overwash. The laboratory results represented good agreement with the field data and might be applicable to predict the shoreline recession by overwash induced by storms. Further improvements can be expected by adding these empirical formulas to a numerical model to predict sediment transport in the swash zone.

Excess sedimentation began affecting the wetland dynamics of Pine Gully in Seabrook, Texas during the first quarter of 2004. This sedimentation was sudden and became a serious problem for the dynamics of the Pine Gully wetland because the fine, well sorted, quartz rich sediments began plugging the main channel of the previously tidally dominated wetland. Progressive sedimentation has produced overbank deposits in the marine grasses, contributing to the death of wetland grasses by sediment chocking. The main purpose of this study is to determine the new source and mechanism of sedimentation in Pine Gully, document changes from sedimentation, and determine a solution to prevent future sedimentation. Sedimentation in Pine Gully and coastal areas adjacent to Pine Gully has occurred in a region that has experienced subsidence and sea level rise. The sedimentation in Pine Gully is a direct result of new and sustained sediment at the mouth of Pine Gully. These new sediments are transported into Pine Gully by displacement waves from ships moving through the Houston Ship Channel. Beach renourishment at Wright Beach, located a half mile north of Pine Gully, occurred as Pine Gully experienced sedimentation. Construction of a breakwater at the mouth of Pine Gully and subsequent removal of sediment in Pine Gully itself is ultimately the solution to revitalizing the wetland to its pre-sedimentation state. Replanting of native vegetation killed off by sedimentation is recommended and would hasten the recovery of the wetland. Documenting the effects of this unique sedimentation in Pine Gully has implications for the future. Beach renourishment or coastal projects that may contribute excess sediment to the coastline should be concerned with unintended effects they may cause. Although an historically eroding shoreline exists, the effects of excess sedimentation can be severe. A coastal study should be done before sediment is added to the shoreline to identify any areas within the sphere of influence of the project. Ecosystems determined to be within the sphere of influence by a coastal study should implement preventative measures at those locations to avoid an ecological disaster similar to that in Pine Gully.

Taiwan is surrounded by the ocean. Her coastal plains are the centers of urbanization and economic developments, where various activities have taken place frequently in the regions abundant in natural resources. Having been benefited by the martial law reinforced until 1988, the natural ecology, landscapes and historical relics in many coastal areas were preserved without large scale development. After the abolition of the martial law, many sensitive and vulnerable coastal areas have been affected by over exploitation or improper shore protection schemes undertaken by public and private sectors without due consideration of their consequence, thus resulting in large scale nearshore reclamations for industrial zones and seawalls incorporating precast armor units to replace the coastal strips that were once beautiful sandy beaches. The engineering works associated with these developments not only have spoiled the natural coastal landscapes but also have caused severe beach erosion, in addition to the adverse impact on sensitive and fragile ecological systems. Located in the west of Kaohsiung city, Sizihwan is not only the facade of the gateway of Kaohsiung international harbor, but also a major attraction for the people living in Kaohsiung to gain intimacy with the sea. The sandy sea shore at Sizihwan, bounded between the rocky hills and the northern breakwater to the Kaohsiung First Harbor, is the precious property of Kaohsiung City. The length of the sandy beach of Sizihwan, about one kilometer originally, was halved resulting from the reestablishment of the National Sun Yat-sen University soon after 1980 for land reclamation to make space for her College of Marine Sciences. Due to increasing number of visitors in recent time under the policy of tourism promotion, it has become vital to recover Sizihwan beach to its past glory. For this reason, the Kaohsiung City Government has determined to undertake this project with a comprehensive investigation, in the hope of making Sizihwan a model of scenic and ecological restoration in Taiwan. This thesis reports in details the process of how the Kaohsiung City Government in carrying out the Sizihwan restoration project since 2005, It consists the complete events from planning, tendering, extra funding to engineering implementation, to serve as the first technical literature in Taiwan for the construction of an artificial headland-bay beach with nourishment. With the support from people in various government authorities, engineering consultants, construction industries and coastal experts in Taiwan, the promotion of beach recovery at Sizihwan has gained sufficient momentum since 2005, aiming to install two artificial headlands incorporating beach nourishment for the provision of a stable sandy bay beach. The author of this report has had the honor in participating in this unique beach restoration project at Sizihwan, as part of his administration duty while serving himself in the Kaohsiung City Government.

Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 81-83). Also available via World Wide Web.

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