The purpose of the Aquatic Natural Zone is to assure the protection of significant fish and wildlife habitats; of continued biological productivity within the estuary; and of scientific, research, and educational needs. These areas are managed to preserve natural resources in recognition of dynamic, natural, geological, and evolutionary processes. Natural aquatic areas include all major tidal marshes, tide flats, and seagrass and algae beds. The designation is intended to preserve those natural aquatic resource systems existing relatively free of human influence.
The following uses and activities and their accessory uses and activities are permitted in the A-3 zone if the Community Development Director determines that the uses conform to the standards in Section 16.80.040, applicable Development Code standards, and other City laws:
A. 
Low-intensity water-dependent recreation.
B. 
Passive restoration.
C. 
Navigational aid, such as beacons and buoys.
D. 
Vegetative shoreline stabilization.
E. 
Emergency repair to existing dikes.
F. 
Marine research and education.
G. 
Piling installation as necessary for permitted uses.
H. 
Similar uses as those listed in this section.
The following uses and activities and their accessory uses and activities may be permitted in the A-3 zone when approved under Chapter 16.220, Conditional Use Permits. They are also subject to the provisions of Section 16.80.040, Development Standards. These uses and activities are also subject to a resource capability determination (Section 16.164.050), and an impact assessment (Section 16.164.010).
A. 
Maintenance and Repair of Existing Structures or Facilities. Temporary encroachments in the floodway for the purposes of bridge construction and repair:
1. 
This use shall comply with Chapter 16.88 (Flood Hazard Overlay (FHO) District) prior to issuance of any permits.
2. 
The temporary permit shall state the number of days the structure or other development will be on the site. If a longer period is required, a new permit shall be issued.
3. 
A flood warning system for the project should be in place to allow equipment to be evacuated from the site and placed outside the floodplain.
4. 
Placement of equipment in the floodway should be restricted to only equipment which is absolutely necessary for the purposes of the project. All other accessory equipment and temporary structures (i.e., construction trailers) should be restricted from the floodway. Structures should be placed on site so that flood damages are minimized. Anchoring the construction trailers in case evacuation is not practical.
B. 
Fill as necessary for the conditional use in subsection A of this section, pursuant to the applicable standards in Chapter 16.160.
C. 
Communication facilities subject to the standards of Chapter 16.148.
D. 
Active restoration.
E. 
Pipeline, cable and utility crossing.
F. 
Dredging as necessary for conditional uses in subsections A through E of this section, pursuant to the applicable standards in Section 16.160.040.
G. 
Aquaculture facilities limited to temporary removable structures which require no dredge or fill.
H. 
Piling as necessary for conditional uses as listed.
I. 
Similar uses as those listed in this section.
The following standards are applicable in the A-3 zone:
A. 
All uses and activities shall satisfy applicable Columbia River Estuary Shoreland and Aquatic Area Development Standards in Chapter 16.160.
B. 
A proposal involving several uses shall be reviewed in aggregate under the more stringent procedure.
C. 
All applicable policies in the City's Comprehensive Plan, mediation panel agreement and goal exceptions shall be met.
D. 
All other applicable Development Code requirements shall also be satisfied.
E. 
A use which requires new dredging, fill, in-water structures, riprap, new log storage areas, water intake, in-water disposal of dredged material, beach nourishment, or other activities which could affect the estuary's physical processes or biological resources is subject to an impact assessment (Section 16.164.010).
F. 
Uses that are not water-dependent shall be located either on a floating structure or on pilings, and shall not increase the need for fill if in association with a water-dependent use located on fill.
G. 
Uses that are not water-dependent shall not preclude or conflict with existing or probable future water-dependent uses on the site or in the vicinity.
H. 
Maximum height of structures shall by 35 feet above MLLW
I. 
Uses that are water-dependent and/or water-related must meet the criteria in Section 16.160.080.
J. 
Uses and activities permitted under Section 16.80.020 of this chapter are subject to the public notice provisions of Section 16.208.040 if an impact assessment is required pursuant to Sections 16.164.010 through 16.164.050, or if a determination of consistency with the purpose of the A-3 zone is required pursuant to Section 16.164.020, or if the Community Development Director determines that the permit decision will require interpretation or the exercise of factual, policy or legal judgment.
K. 
All new sewer and water connections for a proposed development shall comply with all City regulations.