Active Erosion Hazard Zone, Tillamook County, DOGAMI,
2001
Identification_Information
Data_Quality_Information
Spatial_Data_Organization_Information
Spatial_Reference_Information
Entity_and_Attribute_Information
Distribution_Information
Metadata_Reference_Information
Identification Information
Section
Index
Citation:
Citation Information:
Originator: Oregon Department of Geology
and Mineral Industries
Publication Date:
2001
Title: Active Erosion Hazard Zone,
Tillamook County, DOGAMI, 2001
Edition:
Preliminary
Geospatial Data Presentation
Form: vector digital data
Series
Information:
Series Name: Open File
Report
Issue Identification:
O-01-03
Publication Information:
Publication Place: Portland,
Oregon
Publisher: Oregon Department of
Geology and Mineral Industries
Other Citation
Details: A text report accompanies the vector digital
data
Online Linkage:
http://www.oregongeology.com
Larger Work
Citation:
Citation Information:
Originator: Oregon Department of
Geology and Mineral Industries
Publication
Date: 20011231
Title:
Evaluation of coastal erosion hazard zones along dune and bluff backed
shorelines in Tillamook County, Oregon: Cascade Head to Cape
Falcon
Other Citation Details:
Other Digital map data files associated with this Open-file
Report include: Historical shorelines - 1927, 1953, 1955, 1986,
1994, 1997, 1998; Dune hazard data - Neskowin cell beach data,
Netarts cell beach data, Rockaway cell beach data, Sand Lake cell
beach data; Erosion data - Spot erosion rates; Hazard zones - Active
hazard zone, Bluff hazard zones, high dune hazard zone, low dune
hazard zone, moderate dune hazard zone; Landslides - Tillamook
coastal landslides; Misc. geology -Basalt, Slide block widths
Tillamook.
Online Linkage:
http://www.oregongeology.com
Description:
Abstract:
Polygon data capturing Active Hazard Zone for the Tillamook County
coast. The Active Hazard Zone is the area of coastal bluffs and dunes that
is being actively eroded by waves and the mass movements directly
precipitated by wave action. This zone is by its very nature the least
speculative of all of the hazard zones, since it is directly observable
and requires no theoretical projections into the future. On dune-backed
beaches the active hazard zone is mapped at the vegetation line. On bluff
backed shorelines the active hazard zone includes all areas of active mass
movement (soil creep, landslides, etc.) that are driven by coastal
processes; hence it includes the bluff face and ends at the bluff top or
top edge of an active or potentially active coastal landslide. The active
hazard zone was mapped from observations of 1994 aerial photos
supplemented by fieldwork and by analysis of 1998 LIDAR data. This data
set is one portion of a larger study of the entire Tillamook County
Coastline. For full details on study results and methods please consult
DOGAMI Open-file Report O-01-03, and associated digital files.
Purpose:
To assess existing and potential coastal erosion hazards along the
Tillamook County shoreline, extending from Cascade Head in the south to
Cape Falcon in the north. Further, to assist County planners in effective
decisionmaking adjacent to the shoreline.
Supplemental
Information:
An active erosion hazard zone (AHZ) has been identified for the
Tillamook County coastline. For dune-backed shorelines, the AHZ
encompasses the active beach to the top of the first vegetated foredune,
and includes those areas subject to large morphological changes adjacent
to the mouths of the bays due to inlet migration. On bluff-backed
shorelines the AHZ includes actively eroding coastal bluff escarpments and
active or potentially active coastal landslides
The active hazard zone
identified for the Tillamook County coastline varies in width from a few
tens of feet on cliffy headlands to hundreds of feet on low-sloping
beaches (Appendix E). Furthermore, in the Cape Meares area, a large
bedrock landslide reaching 1.3 miles inland has also been included as part
of this zone. It is recalled that on dune-backed beaches, the active
hazard zone distinguishes the zone of beach variability. This is the area
of beach that has undergone considerable change up through April 1998, and
can therefore be expected to experience further changes in the immediate
future. Thus, there can be no doubt that building within the active hazard
zone can represent considerable risk to property and lives.
The
bluff top or active landslide headwall top is an important feature, since
it separates an area of currently active erosion and mass movement from an
area that may become that way some unknown time in the future. All areas
seaward of this feature were mapped as an active coastal erosion hazard
zone. To be conservative, all areas seaward of the headwall of potentially
active landslides were also mapped in the active hazard zone. If there was
some question about whether the landslide was potentially active, then it
was not placed in the active hazard zone. Mapping the active hazard zone
required delineation of the top edge of the bluff and top edge of active
and potentially active landslides. Mapping the landslides was therefore
essential to the project.
Time Period of
Content:
Time Period Information:
Single Date/Time:
Calendar Date: 2001
Time of Day: Unknown
Currentness Reference: 20010625
Status:
Progress: Complete
Maintenance and Update Frequency: None
planned
Spatial Domain:
Bounding Coordinates:
West Bounding Coordinate:
-124.063931
East Bounding Coordinate:
-123.894079
North Bounding Coordinate:
45.803229
South Bounding Coordinate:
45.046984
Keywords:
Theme:
Theme Keyword Thesaurus: NA
Theme Keyword: Beach Morphology
Theme Keyword: Coastal Erosion
Theme Keyword: Geology
Theme
Keyword: Hazard Zone
Place:
Place Keyword Thesaurus: NA
Place Keyword: Tillamook County
Place Keyword: Oregon Coast
Access Constraints: None
Use
Constraints: This regional investigation is not intended for use as
a site-specific analysis tool. It can be used to identify areas in need of
more detailed site-specific geotechnical studies.
Point of
Contact:
Contact Information:
Contact Person Primary:
Contact Person: Jonathan C.
Allan
Contact Organization: Oregon
Department of Geology and Mineral Industries
Contact Position: Coastal geomorphologist
Contact Address:
Address Type: mailing and physical
address
Address: 313 SW 2nd, Suite
D
City: Newport
State
or Province: Oregon
Postal
Code: 97365
Contact Voice
Telephone: 541 574-6642
Contact Facsimile
Telephone: 541 265-5241
Data Set
Credit:
This investigation was supported by a professional services agreement
with Tillamook County and from resources of the State of Oregon Department
of Geology and Mineral Industries (DOGAMI). County funds were derived from
the Project Impact program of the Federal Emergency Management Agency. The
project was greatly facilitated by the Netarts Littoral Cell Management
Planning Project supported by the Oregon Department of Land Conservation and
Development, Oregon Parks and Recreation Division, and Tillamook County. We
are especially grateful to John Beaulieu (Director of DOGAMI), Dennis
Olmstead (Deputy State Geologist), Zhenming Wang (acting Earthquake Program
Director for DOGAMI), Paul Komar (Oregon State University), John Marra
(Department of Land Conservation and Development), Richard Rinne (Hart
Crowser, Inc), and Doug Gless (H.G. Schlicker & Associates, Inc), for
their insightful comments on this report. Thanks must also be extended to
Randy Dana, Department of Land Conservation and Development, for his help in
collating the NOS T-sheets, Chris Chickadel, Oregon State University, for
helping out with the ARGUS photographic data, and James Good, Oregon State
University, who offered helpful advice early on in the project. We are also
extremely grateful to Stuart Albright of Hart Crowser, Inc. for sending
invaluable geotechnical data from The Capes project. Eileen Hemphill-Halley
of the US Geological Survey and University of Oregon kindly provided data
analyses of diatoms present in Quaternary deposits of The Capes landslide.
Native Data Set Environment: Microsoft
Windows Vista Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog
9.3.1.4000
Data Quality Information
Section
Index
Positional Accuracy:
Vertical Positional Accuracy:
Vertical Positional Accuracy Report:
Elevations in this data set are relative to the North American Vertical
Datum of 1988 (NAVD 88)
Lineage:
Source Information:
Source Citation:
Citation Information:
Title: Preliminary report for
Tillamook County shoreline
Source Scale
Denominator: 12000
Type of Source
Media: CD-ROM
Source Time Period of
Content:
Time Period Information:
Range of Dates/Times:
Beginning Date: 1999
Beginning Time: Unknown
Ending Date: 2001
Ending
Time: Unknown
Source
Citation Abbreviation: DOGAMI OFR O-01-03
Source Contribution: Original DOGAMI files were in
MapInfo format, and in UTM Zone 10N NAD27 projection.
Process Step:
Process Description:
For the entire project, the process steps included the following: 1.
Work with local advisory groups to guide the investigation. 2. Obtain
appropriate historical aerial photography. 3. Search the literature for
hazard data. 4. Map existing open coastal shoreline landslides,
classifying them as prehistoric, potentially active, or active. 6.
Collect shoreline topographic profiles and other data necessary to
estimate the width of a zone of shoreline variability on dune-backed
open coastal shorelines. 7. In collaboration with County and technical
advisers, establish a methodology for mapping erosion hazard areas. 8.
Map the erosion hazard areas. 9. Digitize all line data. 10. Transmit
all digital data to County. 11. Provide follow-up advice on use of the
maps in policy development.
Process Date:
1999
Process Step:
Process Description:
The landward extent of the active hazard zone was delineated
according to vegetation and topographic patterns that could be
identified on 1994 aerial photos, with the inclusion of some local
adjustments that were derived from the 1998 LIDAR dataset. The 1998
LIDAR data essentially characterizes those beach changes that occurred
in response to the 1997-98 El Niño. Therefore, the 1998 LIDAR data
provides the most recent assessment available to us, of the shoreline
position along the Tillamook County coastline. Unfortunately, due to the
absence of subsequent LIDAR flights, especially after the particularly
severe 1998-99 La Niña winter storms, we are not able to quantify those
more recent shoreline changes, and therefore provide the most current
assessment of the active hazard zone.
Process
Contact:
Contact Information:
Contact Person Primary:
Contact Person: Jonathan C.
Allan
Contact Organization: Oregon
Department of Geology and Mineral Industries
Contact Position: Coastal
geomorphologist
Contact Address:
Address Type: mailing and physical
address
Address: 313 SW 2nd, Suite
D
City: Newport
State or Province: Oregon
Postal Code: 97365
Contact
Voice Telephone: 541 574-6642
Contact
Facsimile Telephone: 541 265-5241
Process Step:
Process Description:
The original MapInfo Interchage Format files were exported from
CD-ROM and converted to ESRI Shapefile format. The data was reprojected
during this transformation in to the Oregon statewide Lambert
projection.
Process Contact:
Contact Information:
Contact Person Primary:
Contact Person: Tanya C.
Haddad
Contact Organization: Oregon
Coastal Management Program
Contact
Position: Coastal Atlas Coordinator
Contact Address:
Address Type: mailing and physical
address
Address: 800 NE Oregon St,
#1145
City: Portland
State or Province: OR
Postal
Code: 97232
Country:
USA
Contact Voice Telephone:
971-673-0962
Contact Facsimile
Telephone: 971-673-0911
Contact
Electronic Mail Address: tanya.haddad@state.or.us
Cloud Cover: 0
Spatial Data Organization Information
Section
Index
Direct Spatial Reference Method:
Vector
Point and Vector Object Information:
SDTS Terms Description:
SDTS Point and Vector Object Type:
G-polygon
Point and Vector Object Count:
12
Spatial Reference Information
Section
Index
Horizontal Coordinate System Definition:
Planar:
Map Projection:
Map Projection Name: Lambert Conformal
Conic
Lambert Conformal Conic:
Standard Parallel: 43
Standard Parallel: 45.5
Longitude of Central Meridian: -120.5
Latitude of Projection Origin: 41.75
False Easting: 1312335.958
False Northing: 0
Planar
Coordinate Information:
Planar Coordinate Encoding Method:
Coordinate Pair
Coordinate
Representation:
Abscissa Resolution: 0
Ordinate Resolution: 0
Planar Distance Units: international
feet
Geodetic Model:
Horizontal Datum Name: North American
Datum of 1983
Ellipsoid Name: Geodetic
Reference System 80
Semi-major Axis:
6378137
Denominator of Flattening Ratio:
298.257
Entity and Attribute Information
Section
Index
Detailed Description:
Entity Type:
Entity Type Label:
tillamook_cnty_active_hazard_zone_DOGAMI_2001
Attribute:
Attribute Label: Descriptio
Attribute:
Attribute Label: FID
Attribute Definition: Internal feature
number.
Attribute Definition Source:
ESRI
Attribute Domain Values:
Unrepresentable Domain: Sequential
unique whole numbers that are automatically generated.
Attribute:
Attribute:
Attribute:
Attribute Label: Shape
Attribute Definition: Feature geometry.
Attribute Definition Source: ESRI
Attribute Domain Values:
Unrepresentable Domain: Coordinates
defining the features.
Overview
Description:
Entity and Attribute Overview: See
accompanying Open-File Report text for a discussion and explanation of
digital map data attributes.
Entity and Attribute Detail
Citation: Oregon Department of Geology and Mineral Industries
Open File Report O-01-03
Distribution Information
Section
Index
Distributor:
Contact Information:
Contact Person Primary:
Contact Person: Donald
Haines
Contact Organization: Nature of
the Northwest Info Center
Contact
Position: Manager
Contact
Address:
Address Type: physical
address
Address: 800 NE Oregon
Street
City: Portland
State or Province: OR
Postal
Code: 97232
Country:
USA
Resource Description: Active
Erosion Hazard Zone for Tillamook County, DOGAMI, 2001, from OFR
O-01-03
Distribution Liability:
Although these data have been processed successfully on a computer
system at the Oregon Department of Geology and Mineral Industries (DOGAMI),
no warranty expressed or implied is made regarding the accuracy or utility
of the data on any other system or for general or scientific purposes, nor
shall the act of distribution constitute any such warranty. This disclaimer
applies both to individual use of the data and aggregate use with other
data. It is strongly recommended that these data are directly acquired from
DOGAMI, and not indirectly through other sources which may have changed the
data in some way. It is also strongly recommended that careful attention be
paid to the contents of the metadata file associated with these data. The
Oregon Department of Geology and Mineral Industries shall not be held liable
for improper or incorrect use of the data described and/or contained herein.
Standard Order Process:
Digital Form:
Digital Transfer Information:
Custom Order Process: For
the original OFR files in MapInfo format please contact the Oregon Department
of Geology and Mineral Industries
Metadata Reference Information
Section
Index
Metadata Date: 2/22/2013
Metadata Review Date:
Metadata Future
Review Date:
Metadata Contact:
Contact Information:
Contact Person Primary:
Contact Person: Tanya C.
Haddad
Contact Organization: Oregon
Coastal Management Program
Contact
Position: Coastal Atlas Coordinator
Contact
Address:
Address Type: mailing and physical
address
Address: 800 NE Oregon St,
#1145
City: Portland
State or Province: OR
Postal
Code: 97232
Country:
USA
Contact Voice Telephone:
971-673-0962
Contact Facsimile Telephone:
971-673-0911
Contact Electronic Mail
Address: tanya.haddad@state.or.us
Metadata Standard Name: FGDC Content Standards for Digital
Geospatial Metadata
Metadata Standard Version:
FGDC-STD-001-1998
Metadata Time Convention:
local time
SMMS Metadata report generated 2/22/2013