- Table of Contents   Columbia River Estuary Dredged Material Management Plan

List of Tables

List of Figures

Acknowledgments

Introduction
Purpose and Plan Content
Plan Revision Process
Definitions

Guidelines
General Dredging and Disposal
Dredging
Dredged Material Disposal
Site Selection and Site Reservation
Dredging and Dredged Material Disposal Use and Activity

Plan Implementation
Local Jurisdiction Review
Tracking Use of Disposal Sites
Regional Coordination

Site Inventory
Site Inventory
Oregon
Washington
Map

Appendices
Appendix A - Dredging Options
Appendix B - Disposal Options
Appendix C - Beneficial Use Options
Appendix D - Agency Standard Removal/Fill Permit Conditions
Appendix E - Summary of Site Inventory Revisions
Appendix F - Overview of Dredged Material Management Regulations
Appendix G - Summary of Sediment Quality

 

GUIDELINES

Disposal
2. Upland Disposal

i. Dredged material disposal sites shall not impair scenic views and will be completely enclosed by levees or berms of sufficient capacity to allow for the settling of sediments before entrapped water leaves the leveed area. The outside face of the levees shall be sloped at 1 ½ to 1 (horizontal to vertical) or flatter and seeded with grass or otherwise protected to prevent erosion. Outlet structures in levees shall be placed so that water discharged within the levees will take the longest possible time to reach the outlet and shall be designed so that only water having the least possible amount of turbidity is allowed to return to the receiving waters.
ii. Except as noted below, upland disposal and site preparation
shall be conducted such that:

a) Surface runoff from disposal sites is controlled to protect water quality and prevent sedimentation of adjacent water bodies, wetlands, and drainage ways. Disposal runoff water must enter the receiving waterway through a controlled outfall at a location with adequate circulation and flushing characteristics. Underground springs and aquifers must be identified and protected;
b) Levees are constructed according to accepted engineering standards; are adequate to support and contain the maximum potential height and volume of dredged materials at the site; and form a sufficiently large containment area to encourage proper ponding and to prevent the return of dredged materials into the waterway or estuary. Containment ponds and outfall weirs shall be designed to maintain adequate standing water at all times to further encourage settling of dredged materials. The levees shall be constructed within the boundaries of the disposal site and shall be constructed of material obtained from within the site or other approved source.
c) Clean dredged material placed on upland disposal sites located directly adjacent to designated beach nourishment sites may be allowed to flow directly into the waterway without conforming to Items i and ii, above, provided that all policies and standards for in-water disposal and beach nourishment are met and the dredged materials are not allowed to enter wetlands or the waterway in areas other than the designated beach nourishment site.

iii. Upland disposal sites which are not intended for dredged material disposal or development use within a two year period following disposal shall be revegetated with native plant species as soon as site and weather conditions allow, unless habitat management plans agreed upon by resource management agencies specify that open sand areas should remain at the site. The dredging project proponent shall notify the local jurisdiction and State and Federal permitting and resource management agencies when disposal is completed and shall coordinate revegetation with these agencies. The notification shall be sent to at least the following agencies: the local jurisdiction, U.S. Army Corps of Engineers, National Marine Fisheries Service, Soil and Water Conservation District, Natural Resource Conservation Service, Division of State Lands, Oregon Department of Fish and Wildlife, Department of Ecology, Department of Natural Resources, and Washington Department of Fish and Wildlife. Revegetation of a disposal site does not preclude future uses of the sites for dredged material disposal.
iv. The disposal site design shall be reviewed to determine if
wetlands or other habitats will form on the site during the period between disposal actions. The disposal permit may be conditioned to allow future disposal actions to fill the created wetlands or habitats.
v. Oregon jurisdictions add: "The area shall not be a significant
Goal 17 wetland."
vi. The final height and slope after each use of a upland dredged
material disposal site shall be such that:

a) The site does not enlarge itself by sloughing and erosion into adjacent areas;
b) Loss of materials from the site during storms and freshets is minimized;
c) Interference with the view from nearby residences, scenic points, and parks does not occur.

vii. Coordinate with Oregon Division of State Lands or Washington Department of Natural Resources to determine what, if any, royalties are required.