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Figure 1: Location Map West Basin Marina Maintenance Dredging (USGS Astoria, OR 2014) Project Location Columbia River N N NWP-2009-565-1 1 Drawings
Figure 1: Location Map
West Basin Marina Maintenance Dredging (USGS Astoria, OR 2014)
Project Location
Columbia River
N N
NWP-2009-565-1 1 Drawings
Figure 2: Tax Lot Map
West Basin Marina Maintenance Dredging (ORMAP 2017)
Project Area
Yaquina River
N
Columbia River
00100
NWP-2009-565-1 2 Drawings
Figure 3: Aerial Photograph
West Basin Marina Maintenance Dredging (Google Earth 2017)
Columbia River
N
Project Area
1,070 ft.
630' ft.
All docks and piers will remain in place
during dredging. Finger docks average
approximately 30 ft. long by 4 ft. wide.
Main piers average 6 ft. in width.
NWP-2009-565-1 3 Drawings
Figure 4A: Pre-Dredging Surface (2016 Bathymetry)
West Basin Marina Maintenance Dredging (Advanced Remediation Technologies, Inc. 2017)
N Vertical datum is mean low low water (MLLW)
NWP-2009-565-1 4 Drawings
Figure 4B: Dredging Plan (Post-Dredging Surface)
West Basin Marina Maintenance Dredging (Advanced Remediation Technologies, Inc. 2017)
N Vertical datum is mean low low water (MLLW)
NWP-2009-565-1 5 Drawings
Figure 4C: Dredging Cross Sections
West Basin Marina Maintenance Dredging (Advanced Remediation Technologies, Inc. 2017)
HMT (12.0 MLLW)
HMT (12.0 MLLW)
NWP-2009-565-1 6 Drawings
Figure 5A: Dredge Material Disposal Location
West Basin Marina Maintenance Dredging (Disposal location provided by Jon Gornick [Corps Technical Manager for Dredging])
Columbia River
Project Area
Proposed flow lane
disposal location
Submerged disposal pipe
(46.1937 N / -123.8606 W)
(46.1929 N / -123.8604 W)
(46.1933 N / -123.8545 W)
(46.1941 N / -123.8547 W)
N
NWP-2009-565-1 7 Drawings
Figure 5B: Bathymetry of Disposal Location
West Basin Marina Maintenance Dredging (U.S. Army Corps of Engineers 2017)
Columbia River
Project Area
Proposed flow lane
disposal location
N
NWP-2009-565-1 8 Drawings
