1. ERDC Knowledge Core
  2. Engineer Research and Development Center (ERDC)
  3. Coastal and Hydraulics Laboratory (CHL) - (before 9/1981 - present)
  4. Publication
  5. Technical Report
Please use this identifier to cite or link to this item: https://hdl.handle.net/11681/7327
Full metadata record
DC FieldValueLanguage
dc.contributor.authorThomas, Robert C.en_US
dc.contributor.authorDunkin, Lauren M.en_US
dc.creatorCoastal and Hydraulics Laboratory (U.S.)en_US
dc.date.accessioned2016-05-06T14:31:55Zen_US
dc.date.available2016-05-06T14:31:55Zen_US
dc.date.issued2012-07en_US
dc.identifier.govdocERDC/CHL TR-12-11en_US
dc.identifier.urihttp://hdl.handle.net/11681/7327en_US
dc.descriptionTechnical Reporten_US
dc.description.abstractThis report documents the investigation of coastal processes and development of conceptual alternatives to reduce beach erosion at two sites in Matagorda County. Sargent Beach has experienced the greatest erosion rates on the Texas Coast, prompting study into structural methods to protect beach habitat. Additionally, the three miles of beach to the east of the Mouth of the Colorado River is a candidate for structural stabilization. The proximity of the two project areas provided an opportunity to consider processes on a regional scale in an effort to improve regional shoreline stability and further understanding of regional processes. Sargent Beach is comprised of cohesive sediment overlain by a thin veneer of sand. It is located between an ephemeral inlet to the east and a flood relief inlet to the west. The region includes two major river diversion projects, an eight mile long revetment at Sargent Beach, and many other engineering modifications influencing transport. Because of the complex site, an investigation into coastal processes was conducted to determine alternative development. Understanding of physical processes developed during this investigation was applied to develop potential solutions to reduce erosion, including beach nourishment, groins, breakwaters, and installed bypassing systems.en_US
dc.description.sponsorshipUnited States. Army. Corps of Engineers. Galveston Districten_US
dc.description.sponsorshipBay City (Tex.)en_US
dc.description.tableofcontentsAbstract ................................................................................................................................................... ii Figures and Tables .................................................................................................................................. v Preface .................................................................................................................................................. viii Unit Conversion Factors ........................................................................................................................ix 1 Introduction ..................................................................................................................................... 1 1.1 Purpose .......................................................................................................................... 1 1.2 Project locations and history ......................................................................................... 2 1.3 Previous studies ............................................................................................................ 3 1.4 Existing data .................................................................................................................. 4 1.5 Report organization ....................................................................................................... 4 2 Site Conditions ............................................................................................................................... 6 2.1 Water level ..................................................................................................................... 6 2.2 Winds.............................................................................................................................. 7 2.3 Waves ............................................................................................................................. 9 2.4 Relative sea level rise .................................................................................................. 13 2.5 Tropical storms ............................................................................................................. 15 2.6 Shoreline change ......................................................................................................... 16 2.7 Regional geology .......................................................................................................... 19 2.8 Typical beach profile .................................................................................................... 21 2.9 Mechanisms of erosion ............................................................................................... 23 3 Conceptual Sediment Budget ..................................................................................................... 25 3.1 Sediment budget cells ................................................................................................. 26 3.2 Dredging ....................................................................................................................... 27 3.3 Beach volume change ................................................................................................. 27 3.4 River sand supply ........................................................................................................ 28 3.5 Published longshore transport rates .......................................................................... 29 3.6 Cross-shore transport .................................................................................................. 30 3.7 Relative sea level rise .................................................................................................. 30 3.8 Summary and conclusions .......................................................................................... 30 3.9 Recommendations to refine sediment budget in Phase 2 ....................................... 33 4 Coastal Process Model Development: GenCade ...................................................................... 35 4.1 Numerical model approach and conventions ............................................................ 35 4.1.1 Description ................................................................................................................... 35 4.1.2 Units, coordinate system, datum ................................................................................ 36 4.1.3 Direction convention .................................................................................................... 36 4.2 Model domain .............................................................................................................. 36 4.3 Model forcing ............................................................................................................... 36 4.4 Initial shoreline position .............................................................................................. 36 4.5 Inlet shoal volumes ..................................................................................................... 37 4.6 Sediment bypassing .................................................................................................... 38 4.7 Boundary conditions ................................................................................................... 38 4.8 Summary of model parameters .................................................................................. 38 4.9 Model calibration ......................................................................................................... 39 5 Preliminary Analysis of Alternatives .......................................................................................... 45 5.1 Sargent Beach ............................................................................................................. 45 5.1.1 Alternative 0: No Action ............................................................................................... 45 5.1.2 Alternative 1: Beach fill ................................................................................................ 46 5.1.3 Alternative 2: Single groin east of Mitchells Cut plus beach fill ................................ 50 5.1.4 Alternative 3: Groin field plus beach fill ...................................................................... 52 5.1.5 Alternative 4: Breakwaters .......................................................................................... 55 5.1.6 Alternative 5: Transition breakwaters ......................................................................... 59 5.2 Matagorda Peninsula .................................................................................................. 62 5.2.1 Alternative 0: No Action ............................................................................................... 62 5.2.2 Alternative 1: Groin and bypassing system ................................................................ 64 5.2.3 Alternative 2: Breakwaters and bypassing system .................................................... 66 5.3 Alternative comparison ............................................................................................... 66 5.3.1 Sargent Beach .............................................................................................................. 66 5.3.2 Matagorda Peninsula ................................................................................................... 68 6 Summary and Conclusions .......................................................................................................... 70 6.1 Phase 2 tasks .............................................................................................................. 72 References ............................................................................................................................................ 73 Appendix A: Overview and Shoreline Change Figures ..................................................................... 76 Appendix B: Sediment Budget Figures ............................................................................................. 83 Appendix C: Preliminary Alternative Layout ..................................................................................... 87 Appendix D: Historical Aerial Imagery ............................................................................................... 95 Report Documentation Pageen_US
dc.format.extent113 pages/14.12 MBen_US
dc.format.mediumPDFen_US
dc.language.isoen_USen_US
dc.publisherEngineer Research and Development Center (U.S.)en_US
dc.relationhttp://acwc.sdp.sirsi.net/client/en_US/search/asset/1007587en_US
dc.relation.ispartofseriesTechnical report (Engineer Research and Development Center (U.S.)) ; no.ERDC/CHL TR-12-11en_US
dc.rightsApproved for public release; distribution is unlimiteden_US
dc.sourceThis Digital Resource was created from scans of the Print Resourceen_US
dc.subjectBeach erosionen_US
dc.subjectBeach nourishmenten_US
dc.subjectBreakwateren_US
dc.subjectCoastal structuresen_US
dc.subjectGroinen_US
dc.subjectSediment budgeten_US
dc.subjectShoreline changeen_US
dc.subjectTexas Gulf Coasten_US
dc.titleErosion control and environment restoration plan development, Matagora County, Texas: Phase 1: Preliminary investigationen_US
dc.typeReporten_US
Appears in Collections:Technical Report
Technical Report

Files in This Item:
File Description SizeFormat 
CHL-TR-12-11.pdfERDC/CHL TR-12-1114.12 MBAdobe PDFThumbnail
View/Open
Show simple item record