Overall costs of maintaining authorized or required project depths in the navigation channels and harbors of the United States by dredging have increased dramatically during the last decade. To reduce these costs by extending the interval between maintenance dredging operations - - and to provide full project dimensions for a greater period of time -- advance maintenance is performed at critical shoaling areas of many navigation projects. Advance maintenance is dredging done beyond the existing authorized depth of a project to provide a predetermined amount of catchment capacity below design depth. It is exclusive of the allowable dredging tolerance (usually 1 to 2 ft) common to most dredging operations which compensates for inaccuracies inherent to the practice. This report, the third of a series, examined and evaluated the effectiveness of advance maintenance dredging in producing desired results for six selected navigation channel segments. These segments are: Shipyard River, S.C., Coos Bay, Oreg. (miles 0 to 1 and 12 to 15), and three reaches of the Columbia River, Oreg .-Wash., between miles 73 and 84. This was accomplished by comparing shoaling rates and distributions and dredging frequencies resulting from maintenance operations on these projects which included advance maintenance with others which did not. Data used were obtained from predredge and postdredge surveys and other pertinent dredging information from Corps district offices and annual reports of the Chief of Engineers. Results indicated that advance maintenance was beneficial in some, but not all, cases and that it should be evaluated on a case-by-case basis.


    Zugriff

    Download


    Exportieren, teilen und zitieren



    Titel :

    Effects of Depth on Dredging Frequency. Report 3: Evaluation of Advance Maintenance Projects



    Erschienen in:

    Technical Report ; H-78-5 rept.3


    Erscheinungsdatum :

    1985


    Format / Umfang :

    3596562


    Medientyp :

    Report


    Format :

    Elektronische Ressource


    Sprache :

    Englisch



    Klassifikation :


    Dredging/Projects

    Online Contents | 2013


    Dredging Projects

    Online Contents | 2013


    Effects of Depth on Dredging Frequency. Report 1: Survey of District Offices

    Trawle, Michael J. / Boyd, Jesse A. Jr. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1978

    Freier Zugriff

    Effects of Depth on Dredging Frequency. Report 2: Methods of Estuarine Shoaling Analysis

    Trawle, Michael J. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1981

    Freier Zugriff