14.250.300 Regulations Specific to Grading, Filling, Dredging, and the Disposal of Dredge Material.
A. Grading, dredging, and filling shall be located, designed, and conducted to protect shoreline ecological functions and ecosystem-wide processes, including channel migration, and mitigation shall employ the mitigation sequence specified by Chapter 14.255 SMC.
B. Grading, dredging, dredge material disposal and filling shall be consistent with Chapter 14.270 SMC.
C. Fill may be permitted below the ordinary high water mark only:
1. When necessary to support a water-dependent use;
2. To provide for public access;
3. When necessary to mitigate conditions that endanger public safety, including flood risk reduction projects;
4. To allow for cleanup and disposal of contaminated sediments as part of an interagency environmental cleanup plan;
5. To allow for the disposal of dredged material considered suitable under, and conducted in accordance with, the Dredged Material Management Program of the Washington Department of Natural Resources;
6. For expansion or alteration of transportation or utility facilities currently located on the shoreline upon demonstration that alternatives to fill are not feasible; or
7. As part of mitigation actions, environmental restoration projects and habitat enhancement projects.
D. Dredging and disposal of dredged material below the ordinary high water mark shall be permitted only:
1. When necessary for the operation of a water-dependent use;
2. When necessary to mitigate conditions that endanger public safety or fisheries resources;
3. For establishing, maintaining, expanding, relocating or reconfiguring navigation channels and basins when necessary to ensure safe and efficient accommodation of existing navigation uses where:
a. Significant ecological impacts are minimized and mitigation is provided;
b. The substantive requirements of Chapter 14.255 SMC are satisfied; and
c. Dredging is maintained to the authorized location, depth and width;
4. For restoration projects associated with implementation of the Model Toxics Control Act or the Comprehensive Environmental Response, Compensation, and Liability Act; or any enhancement or restoration project;
5. For flood risk reduction projects conducted in accordance with Chapter 14.270 SMC.
E. Dredging and dredge material disposal shall be performed in a manner which avoids or minimizes significant ecological impacts. Impacts that cannot be avoided should be mitigated in a manner that assures no net loss of shoreline ecological functions.
F. Maintenance dredging of established navigation channels and basins should be restricted to maintaining previously dredged and/or authorized location, depth, and width.
G. Dredging is not allowed waterward of the ordinary high water mark for the primary purpose of obtaining fill material except where the material is necessary for the restoration of ecological functions. Where permitted, the site where the fill is to be placed must be located waterward of the OHWM and the action must be required for an approved habitat enhancement project.
H. Disposal of dredged material shall be allowed only in approved disposal sites.
I. Stockpiling of dredged material in wetlands and habitat conservation areas and their associated buffers, and in or under water, is prohibited.
J. No dredging may commence in any shoreline environment without the responsible person having first obtained either a substantial development permit or a determination of exemption.
K. The removal of gravel for flood management is allowed only after biological and geomorphological studies show that extraction has a long-term benefit to flood hazard reduction, results in no net loss of ecological functions, and is part of a comprehensive flood management solution.
L. Dredging in or the disposal of dredge spoils on known archaeological sites is prohibited unless approved in writing by the Department of Archaeology and Historic Preservation in consultation with any affected tribes.
M. Applications for dredging permits shall include the following information (at a minimum):
1. Physical analysis of material to be dredged: material composition and amount, grain size, organic materials present, source of material, etc.;
2. Chemical analysis of material to be dredged: volatile solids, chemical oxygen demand (COD), grease and oil content, mercury, lead and zinc content, etc.;
3. Biological analysis of material to be dredged;
4. Information on stability of bedlands adjacent to proposed dredging and spoils disposal;
5. Dredging procedure: time of dredging, method of dredging, and spoils disposal; and
6. Dredge spoils disposal area: location, size, capacity, and physical characteristics.
N. New dredging projects shall, in addition to the above, provide the following information with their application:
1. Total initial spoils volume;
2. Frequency and quantity of project maintenance dredging;
3. Area proposed for initial spoils disposal; and
4. Provisions for long-term/ongoing disposal of maintenance spoils.
O. Applications for dredge spoils disposal sites shall include the following, whether in the City of Snohomish shoreline jurisdiction or elsewhere:
1. Disposal site area and final depth of spoils;
2. Methods to control water quality from spoils, including a perimeter dike or similar control system, and methods of ingress and egress from the spoils site that will not result in off-site water quality impacts;
3. A landscaping plan providing landscape screening and erosion control during the period of disposal; and
4. A description of the ultimate use of the site after spoil disposal is complete.
P. New development shall be sited and designed to avoid the need for new and maintenance dredging. (Ord. 2336, 2018)