SalmonChinook_SnakeRiverspringsummerrunESU_19991025

Data creation process 2023.

FINAL_CH_SNRspsuChk_POST_PROCESSED_v2.shp

Snake River (SNR) spring/summer-run Chinook data were developed as part of an effort to interpret and depict several salmonid critical habitat designations completed in the 1990s that relied on text-based descriptions but lacked GIS data.

Critical habitat areas were identified based on the following:

- The regulatory definition of ESA critical habitat for this ESU found at 50 CFR 226.205 (b) and the supporting final rule (58 FR 68543, December 28, 1993) and revision (64 FR 57399, October 10, 1999);

- United States Geological Survey (USGS) high resolution National Hydrography Dataset (NHD) downloaded February 2018;

- Intrinsic Potential (IP) data developed by the Northwest Fisheries Science Center (NWFSC);

- Technical Recovery Team (TRT) fish population data developed by the NWFSC;

- National Elevation Data and Digital Topographic Maps;

- Oregon Fish Passage Barriers Geodatabase (ODFW_44_5_ofpbds_gdb, published 2020-05-28);

- Washington Fish Passage Barriers Geodatabase (WdfwFishPassage.gdb, published 2021-03-15);

- Idaho Fish Passage Barriers shapefile (downloaded 2021-03-18);

- StreamNet Generalized Fish Distribution, Summer Chinook (January 2012);

- StreamNet Generalized Fish Distribution, Spring Chinook (January 2012);

- Columbia River Intertribal Fish Commission (CRITFC) data (critfc_chinook_extent_May2020.shp) historic and current spring chinook salmon distribution in the Grande Ronde River basin;

- United States Forest Service (USFS) and Bonneville Power Administration (BPA) juvenile Chinook density model output (FDAT_Phase2_Chinook_StreamSegmentScenarios_DensityResults.shp published 2020-04-30);

- Snake River steelhead DPS critical habitat data (2005-08-15) used as a proxy;

- The professional judgment of biologists from NMFS West Coast Region (Interior Columbia Basin Office and Protected Resources Division).

Spatial analysis steps to produce data:

1) Clipped the NHD to the text description from the critical habitat designation.

2) Partitioned the NHD into 100 meter segments.

3) Calculated the gradient of each 100 meter segment using a 10 meter USGS digital elevation model (DEM).

4) Used the NHD's flow direction and a geometric network to analyze gradient, removed segments upstream of 7% gradients.

5) Retained segments downstream of 7% gradients that were too small (<= 20 meters) to rely on the gradient value (i.e., 1 to 2 pixels in the DEM) or were artificial paths (NHD FCode 55800) to maintain network connectivity.

6) Removed intermittent and ephemeral streams, canals/ditches, and pipelines according to NHD FCodes.

7) Retained segments that overlapped with StreamNet chinook distribution data (field observations) and/or NWFSC intrinsic potential data (model).

8) Removed segments upstream from total natural barriers, Napias Ck falls, Dworshak Dam, Hells Canyon Dam.

9) Removed segments identified by NMFS biologists as not being accessible to or suitable habitat for Chinook salmon.

10) Retained segments identified by NMFS biologists as being flagged for inclusion as critical habitat (e.g., NHD errors where streams were disconnected from mainstems, presumed historical habitat above 7% gradient breaks, etc.).

11) The output was FINAL_CH_SNRspringsummerChinook.shp (final critical habitat footprint in 100 meter segments) which was then post processed and exported into FINAL_CH_SNRspsuChk_POST_PROCESSED_v2.shp. Post processing involved using the final source data to clip the 2018 NHD Flowline, i.e., remove 100 meter segments to reduce number of vertices and capture the critical habitat footprint on the original 2018 Flowline. Process captured in FINAL_POST_PROCESSING_SNRspsuCHK_ch.gdb.

Converted source data FINAL_CH_SNRspsuChk_POST_PROCESSED_v2.shp (GCS_North_American_1983) into standardized feature class SalmonChinook_SnakeRiverspringsummerrunESU_19991025 (GCS_WGS_84 wkid 4326) using the West Coast Region Critical Habitat Geodatabase processing protocol.

During standardization, geometry was not edited. Attributes were edited. Metadata was edited and populated using the final rules/CFR and the source FINAL_CH_SNRspsuChk_POST_PROCESSED_v2.shp (GCS_North_American_1983).

Migrated field: "GNIS_Name" into "UNIT".

Dropped fields: OBJECTID, Permanent_Identifier, FDate, Resolution, GNIS_ID, LengthKM, ReachCode, FlowDir, WBArea_Permanent_Identifier, FType, FCode, MainPath, InNetwork, VisibilityFilter, Shape_Length.