الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
El-Alamein new city (ANC) is situated on the northwestern coast of Egypt, extending 110 km from Alexandria. The city is being constructed to meet the high standards requested of a fourth generation city, which is projected to house millions of citizens, representing a major accomplishment for the North Coast region and the beach stretches for over 14 km. The study area is divided into 3 zones. ANC is on the western side of the study area (zone1) for 14 km, Marina village is on the middle side (zone2) for 12 km, and El-Alamein down drift area (ElAhlam and El Louts village...) is on the eastern side (zone3) for 12 km. Internal artificial lagoons will be included in the planned city’s design with inlets at the Mediterranean Sea. As a consequence, hard structures such as jetties and groins will be constructed to partially reduce the strength of attacking waves and scientifically minimize sedimentation at lagoon inlets, which helps to renew water and increase the quality of internal lakes. Study similar near projects as Marina to protect the entrances of the artificial lagoon’s inlets of EL Alamein New City is one of the main objectives of the study. Marina resort lagoons and protections are considered as a prototype for ANC in hopes of avoiding its negative impacts on the study area. In March 2019 and March 2021, hydrographic surveying was conducted twice for ANC, where topographic and hydrographic surveying was implemented over approximately 40 km to cover the study area from Badr village in the east to Al-Hamra harbor in the west for 80 profiles, extending 1.5 km from the shoreline to create extensive bathymetric maps and represent the bottom characteristics, and used as inputs for numerical models. Thirty-four sediment samples collected from the study, and geomorphological analysis for the shoreline samples to estimate the geological characteristics in front of the study area. Therefore, there are three types of shorelines: rock, sand, and rock with sandy shoreline. Shoreline erosion at down drift area of coastal jetties and sedimentation at lagoons inlets are considered the critical issues which shall be balanced and modeled so the effect of coastal structures – jetties and groins – in front of Marina village was evaluated using remote sensing imagery and the Digital Shoreline Analysis System (DSAS) software to evaluate historical shoreline changes from 1988 to 2021. For Marina resort lagoons case study, shoreline change shave been digitized for google earth historical images between 1988 to 2021 by using the Digital Shoreline Analysis System (DSAS) software. Cutting natural longshore current drift by Marina jetties has significantly eroded the down drift area eastern of Marina border with an average rate of -5 m/ year for 1988 to 2001 and -18 m/ year for 2005 to 2019. Highly rates of erosion with an average rate of -54 m/year were digitized between 2019 to 2021 according to starting of ANC coastal proposed structures. Historical analysis of shoreline changes for the long term clarify that Marina was the main reason for preventing the movement of the longshore current to the eastern side of Marina to cause significant erosion in front of the down drift village since 1988 till 2018 also the rates of accretion decreased from +27 m/year before the construction of Marina jetties to +6 m/year during the construction to reach 19 m/year after the construction of jetties and groins, also the rate of accretion increased again because the cycles of sand nourishment around the coastal structures on the other side the rate of erosion increased from - 5 m/year to - 18 m/year. The analysis of the short term of shoreline changes by using real measured data aid to estimate more accurate shoreline changes rates therefore the rate of accretion increased to be +52 m/year because the new man-made coastal protection structures at the eroded unstable beaches as Petro Beach, presidential Palace, and El Masa platform which aid to protect the shoreline from erosion. The construction of the two jetties at the first eastern lagoon inlet in front of ANC cause significant erosion in front of Marina 7 therefore reservation of large quantities of sediments at up drift area. The main target of the study is to estimate the effects of the coastal protection structures of Marina at the down drift area and assessment the construction ages of ANC to protect the entrances of artificial lakes inlets and its effect at the down drift area in front of marina7and evaluation of the different scenarios for the inlet’s coastal protection structures.