Tags
The Flow_zone attribute provides an identification number for each evacuation flow zone. The actual value is arbitrary; the intention is to allow a user to differentiate flow zones in order to more clearly see the larger evacuation regime for a region. Flow_zone IDs link with the corresponding Evacuation Route feature class Flow_zone IDs.
Symbolize with arrow at end, using the right arrow symbology, to see direction of line segments. This feature class contains a single data-bearing attribute: Flow_zone contains the evacuation flow zone (using the XXL1 tsunami scenario) associated with each evacuation route.
We evaluated pedestrian evacuation in the Nehalem Bay area of Tillamook County, Oregon in the event of a local tsunami generated by an earthquake on the Cascadia subduction zone (CSZ). Our analyses focused on a maximum-considered CSZ tsunami event covering 100% of potential variability, termed XXL1 and generated by a magnitude 9.1 earthquake. This feature class shows the most efficient routes to safety for every point in the inundation zone (on the road and trail network) assuming all non-retrofitted bridges within the inundation zone fail due to earthquake shaking. Symbolize with arrow at end, using the right arrow symbology, to see direction of line segments. See the text from this Open-file Report O-20-07 for technical information on mapping methods and a discussion of results and interpretation.
The purpose of this data is to provide local government with a quantitative assessment of pedestrian evacuation in order to evaluate mitigation options such as evacuation route improvements, better wayfinding, land use planning actions, and potential vertical evacuation options.
None
REPORT DATA: This product is for informational purposes and may not have been prepared for or be suitable for legal, engineering, or surveying purposes. Users of this information should review or consult the primary data and information sources to ascertain the usability of the information. This publication cannot substitute for site-specific investigations by qualified practitioners. Site-specific data may give results that differ from the results shown in the publication. See the accompanying text report for more details on the limitations of the methods and data used to prepare this publication.
When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregongeology.org
This project was funded by the National Oceanic and Atmospheric Administration (NOAA) through the National Tsunami Hazard Mitigation Program under award No. NA18NWS4670076.
All attributes were checked using automated QAQC tools designed specifically for tsunami data. Attributes were also reviewed visually in ArcGIS.
The following topology checks were performed and any errors were resolved: Must Be Single Part, Must Not Intersect, Must Not Self Intersect and Must Not Self-Overlap.
This feature class provides the most efficient routes to safety for every point in the inundation zone along all road, trail, and beach networks (per local government review) for the Nehalem Bay area of Tillamook County, Oregon. This is defined as the area from Neakahnie Beach in the north down to mouth of the Nehalem River in the south. To the east it extends slightly upstream of the MacDonald Dike Rd bridge on the North Fork of the Nehalem River, and slightly upstream of the Highway 53 bridge on the Nehalem River.
Horizontal positional accuracy is very good because most roads and trails have 1) either been digitized based on lidar or 2) have been checked for accuracy against lidar.
Not Applicable
This feature class was generated using Esri ArcGIS 10.7 and Esri ArcPro 2.5 software. The path distance tool uses geospatial algorithms to calculate the most efficient route from each point in the evacuation zone to safety. Inputs include sub-sampled lidar and a road and trail network. Additional ArcGIS tools used to convert path distance results to evacuation routes include several from the Hydrology Toolbox and the backlink raster. Most of the methodology for these processes are described in Priest et al, 2016 and Gabel et al, 2018b. The source tsunami modeling data can be found in Priest et al, 2013a and Priest et al 2013b. See the text from this open-file report for technical information on mapping methods.
When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregongeology.org
Symbolize with arrow at end, using the right arrow symbology, to see direction of line segments. This feature class contains a single data-bearing attribute: Flow_zone contains the evacuation flow zone (using the XXL1 tsunami scenario) associated with each evacuation route.
When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregongeology.org
Although these data have been processed successfully on a computer system at the Oregon Department of Geology and Mineral Industries, no warranty expressed or implied is made by DOGAMI regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty.
When contacting DOGAMI about this data set, please reference the data set title or other identifying information in your correspondence. DOGAMI publications can be downloaded from https://www.oregongeology.org