Alan Rea Kenneth D. Skinner 2009 vector digital data U.S. Geological Survey Data Series 412 Reston, VA U.S. Geological Survey http://water.usgs.gov/lookup/getspatial?ds412_perennialstreamsevents Alan Rea Kenneth D. Skinner 2009 raster and vector digital data U.S. Geological Survey Data Series 412 Reston, VA U.S. Geological Survey http://pubs.usgs.gov/ds/412/ Perennial streams in Idaho have been modeled using regression equations for 7-day, 2-year low flows (7Q2) described in Wood and others (2009, U.S. Geological Survey Scientific Investigations Report 2009-5015). The model produces "synthetic" streams based on 10-meter resolution digitial elevation models that have been processed to agree closely with 1:24,000-scale National Hydrography Dataset flowlines. See Larger_Work_Citation report text for a complete description of the modeling process. In this dataset, the synthetic stream lines have been indexed to the NHDPlus Version 01_02 (schema version 1, data version 2). Points along the synthetic streams where 7Q2 model estimates exceeded 0.1 cubic feet per second were snapped to the NHDPlus 1:100,000-scale flowlines, and then traced downstream using the NHDPlus network. The data are presented in the form of a dBase-format event table. The traced line events correspond to synthetic stream lines having PerCode values of 2 or 3. The model was developed to provide a more consistent and uniform representation of perennial streams in Idaho than was provided by the hydrographic categories of the National Hydrography Dataset, as of 2004. Additional information regarding the modeling of 7Q2 flows and perennial streams in Idaho may be found in the following report: Wood, Molly S., Rea, Alan, Skinner, Kenneth D., and Hortness, Jon E., Estimating Locations of Perennial Streams in Idaho Using a Generalized Least-Squares Regression Model of 7-Day, 2-Year Low Flows, U.S. Geological Survey Scientific Investigations Report SIR 2009-5015, 2009, U.S. Geological Survey. 2008 publication date Complete None planned -118.566350 -110.219926 49.048670 41.088104 None inlandWaters perennial streams hydrography National Hydrography Dataset NHD National Hydrography Dataset Plus NHDPlus GCMD Location Keywords Idaho ID NORTH AMERICA UNITED STATES UNITED STATES OF AMERICA None None U.S. Geological Survey Ask USGS -- Water Webserver Team mailing address

507 National Center

Reston VA 20192 USA 1-888-275-8747 (1-888-ASK-USGS) http://answers.usgs.gov/cgi-bin/gsanswers?pemail=h2oteam&amp;subject=GIS+Dataset+ds412_perennialstreamsevents Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.2.4.1420 Comparisons of the modeled perennial streams with field observations are described in detail in Wood and others (2009). Different regression models were applied to eight different regions in Idaho. Differences in drainage density may be observed at the boundaries between regions. The region boundaries were determined based on similarity of basin characteristics at stream-gage locations, geographic and geomorphic features such as mountain ranges or breaks between mountains and plains, and professional judgement. Extensive checking or editing of the resulting dataset is beyond the scope of this project. A known issue is that features estimated to be perennial streams in the synthetic streams dataset may have no corresponding feature in the 1:100,000-scale NHDPlus flowline feature class. Often this is due to scale generalization in the NHD. No attempt has been made to address these discrepancies. The synthetic streams dataset (ds412_SyntheticPerennialStreams.shp) more completely represents the modeled results, but does not provide any direct linkage to the NHD. The model was not developed for the eastern Snake River Plain. This undefined area is delineated in the low-flow regions grid "id_lowreg" in the statewide datasets group included in Data Series 412 (see Larger Work Citation). U.S. Geological Survey 2004 Sioux Falls, SD U.S. Geological Survey http://ned.usgs.gov/ 24000 disc 2004 publication date 1/3-second NED elevation grid U.S. Geological Survey in cooperation with U.S. Environmental Protection Agency, USDA Forest Service, and other Federal, State and local partners 2004 vector digital data http://nhd.usgs.gov/ 24000 disc 2004 publication date High-Resolution NHD hydrography used to burn into elevation model Idaho Department of Water Resources and others Unpublished Material 200506 vector digital data http://www.idwr.idaho.gov/watersheds/default.htm 24000 disc 200506 publication date Idaho 2005 Draft WBD 8-digit HUC boundaries were used as "walls" around processing units Molly S. Wood Alan Rea Kenneth D. Skinner Jon E. Hortness 2009 model U. S. Geological Survey Scientific Investigations Report 2009-5015 Boise, ID U.S. Geological Survey http://pubs.usgs.gov/sir/2009/5015/ paper 2009 publication date Wood and others 2009 regression equations for 7Q2 U.S. Environmental Protection Agency (USEPA) and the U.S. Geological Survey (USGS) 2005 V01_02 vector digitaldata http://www.horizon-systems.com/nhdplus/ 100000 disc 2005 publicationdate NHDPlusV01_02 linear referencing system to which synthetic streams wereindexed Development of Hydro-Enforced DEMs. See USGS Data Series Report 412 for complete process description. 1/3 arc-second NED High-resolution NHD Idaho 2005 Draft WBD 2007 HydroDEM Applied regression equations to estimate 7Q2 flows for every grid cell for each region. Added and subtracted standard errors to compute ranges of flows representing uncertainty levels. Classified grids into uncertainty ranges and converted to vector shapefile. HydroDEM Wood and others 2009 2007 ds412_SyntheticPerennialStreams The following procedure was followed to transfer the model of perennial streams to the NHDPlus as linear events. 1. The synthetic streams shapefile was converted to an Arc/Info coverage, and nodes were built. The NODETYPE field was added to the NAT. 2. Relates were set up in Tables between NAT and AAT for incoming arcs and outgoing arcs. Reselects were done to select for the following conditions, which were then coded in the NODETYPE field: NODETYPE CONDITION 12 Grid_code 1 flowing to a Grid_code 2 (this is where 7Q2 = .1) 13 Grid_code 1 flowing to a Grid_code 3 23 Grid_code 2 flowing to a Grid_code 3 3. Only the above nodes (79,071 of them) were saved out to a shapefile named syntheticnodes_1_2_3. 4. The NEAR tool (from toolbox Analysis Tools) was used with a 500 meter search radius to match the nearest Flowlines in the Med Res NHD (from NHDPlus). The large radius was used to see the distribution of distances. The vast majority are less than 100 m. 5. The syntheticnodes_1_2_3 points having "NEAR_DIST" <= 100 AND "NEAR_FID" = 0 were selected. There are 54,007 points meeting these criteria. These were exported to a file named near_nodes.dbf. This file was loaded into ArcMap using Add XY data and the NEAR_X and NEAR_Y coordinates (the points falling on the Flowlines). This was then exported to the pstrms_nodes feature class in the Drainage feature dataset in the NHDMedResID.mdb geodatabase. 6. The NHDMedResID.mdb contains the Drainage feature dataset, in US Albers projection. The NHDFlowline shapefile was loaded into it as Flowline, loading only the flowlines having FLOWDIR of "With Digitized", and dropping the ENABLED field. 7. Before the network could be built, the pstrms_nodes feature class needed Z values in order to match the Flowlines. (It had None for Z Coordinate system, but was still type PolylineZM.) So the pstrms_nodes feature class was copied with the Copy Feature tool, and the Output has Z Values General Environment setting was set to Enabled. The old pstrms_nodes feature class was deleted, then the copy renamed to pstrms_nodes. 8. A Geometric network was created using Flowline. No complex edges were used. The snap tolerance was set to 0.001 meters, and Flowline was allowed to snap. There were no sources/sinks, and no weights. 9. The network was added to ArcMap, along with pstrms_nodes. The NODETYPE (short integer) field was added to Drainage_Net_Junction feature class so pasted values would be carried over. 10. The Point Distance tool was used to identify pstrms_nodes points within 2 meters of Drainage_Net_Junctions. These will cause problems because they can't be pasted on top of existing junctions. A join was made from the Drainage_Net_Junctions table to the node_junc_dist table (result of Near), then another join was added to the pstrms_nodes table using the Near_FID linked to ObjectID. The Drainage_Net_Junctions were selected using query: pstrms_nodes.NODETYPE = 0 745 records were selected. (There were 759 records in the distance table, so somewhere we lost 14 records.) The table was opened for editing and the Drainage_Net_Junctions.nodetype field was calculated to be equal to [pstrms_nodes.NODETYPE]. 11. The Point Distance tool was used to find pstrms_nodes within 2 meters of each other. The DONOTUSE field was added to the resulting pstrms_pstrms_dist table. Records that were duplicates (INPUT_FID eq NEAR_FID,) were unselected. The 84 records with distance less than 1 meter of each other were true duplicates and should not be pasted on top of each other. The distance table had two records for each FID, so I manually unselected one of each pair, then calculated DONOTUSE to 1 for those records. A join from pstrms_nodes to pstrms_pstrms_dist was set up, and the DONOTUSE field was computed for matching records in pstrms_nodes. 12. A relate was set up from node_junc_dist to pstrms_nodes, using Input_FID linked to ObjectID. All records in node_junc_dist were selected (759 records), then the relate was followed to pstrms_nodes, where 759 records were selected. The records having DONOTUSE = 1 were added to the selected set, resulting in 788 records selected. The pstrms_nodes selection was switched so the nodes within 2 meters of existing junctions were not selected. At that point, 53,219 nodes were selected. Because ArcMap crashed when pasting the entire dataset, it was broken into pieces by adding the PASTEGRP field and calculating it = OBJECTID mod 10. The records in node_junc_dist were unselected. The geodb was opened for editing, with Drainage_Net_Junctions set as the target layer. The Editor Options snapping tolerance was set to 1 meter. The first group of pstrms_nodes (pastegrp = 0) were selected. Then the nodes were copied and pasted into Drainage_Net_Junctions. ArcMap was closed, a copy of the GeoDB was made, and the process repeated for each of the 10 groups. The GeoDB was compacted after each 2nd or 3rd group. The ArcHydro Tools were used to set the flow direction on the network. 13. The Drainage_Net_Junction feature class was selected for [nodetype] 0 (the ones pasted from pstrms_nodes). The Flags on Selected Junctions tool (downloaded from ESRI EDN web site) was used to set junction flags on each of these selected junctions. 14. The Utility Network Analyst toolbar was used with Trace Downstream Task, and output set to select features. The selected Flowline features were exported to a new feature class in the geodb (named pstrmslines). 15. The Locate Features Along Routes GP tool was used to make output event table temp_events.dbf, using pstrmslines as input features, Flowline as Input Route Features, COMID as Route Identifier Field, search radius 0, and other options defaulted. 16. Some very small negative values on FMEAS were found in the data. to correct this, FMEAS and TMEAS values were rounded to 3 decimal places by making an info table out of it in ArcMap, adding double-type fields with precision 7 and scale 3, calcing to those fields, then calcing back to FMEAS and TMEAS, and exporting back to DBF format. This eliminated the tiny negative FMEAS values. 17. The Dissolve Route Events tool was used to eliminate duplicative events. The REACHCODE attribute was added and computed by joining to the original NHDPlus data. Three short remaining duplicate events were found and were removed. 18. The RID field was a long integer and contained COMIDs, so it was dropped from the event table, leaving just FMEAS, TMEAS, and REACHCODE attributes. ID_SyntheticPerennialStreams NHDPlus V01_02 20080410 ID_PerennialStreamsEvents Alan Rea U.S. Geological Survey Hydrologist mailing and physical address

230 Collins Road

Boise ID 83702 USA 208-387-1323 ahrea@usgs.gov Vector String 69570 Transverse Mercator 0.999600 -114.000000 42.000000 2500000.000000 1200000.000000 coordinate pair 1.0 1.0 meters North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222 ID_PerennialStreamsEvents dBase event table NHDPlus V01_02 and ID_SyntheticPerennialStreams OID Internal feature number. ESRI Sequential unique whole numbers that are automatically generated. FMEAS From Measure, in percent along reach, from downstream to upstream NHDPlus 0 100 TMEAS To Measure, in percent along reach, from downstream to upstream NHDPlus 0 100 REACHCODE Unique ID from NHD for reach being referenced NHDPlus REACHCODE of referenced NHDPlus flowline feature U.S. Geological Survey Ask USGS -- Water Webserver Team mailing address

455 National Center

Reston VA 20192 USA 1-888-275-8747 (1-888-ASK-USGS) http://water.usgs.gov/user_feedback_form.html Downloadable Data Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of these data, software, or related materials. The use of firm, trade, or brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey. The names mentioned in this document may be trademarks or registered trademarks of their respective trademark owners. DBF 4 dBase file 0.8 MB http://water.usgs.gov/GIS/dsdl/ds412/index.html None 20080531 U.S. Geological Survey Ask USGS Ask USGS -- Water Webserver Team mailing address

455 National Center

Reston VA 20192 USA 1-888-275-8747 (1-888-ASK-USGS) http://answers.usgs.gov/cgi-bin/gsanswers?pemail=h2oteam&subject=GIS+Dataset+ds412_perennialstreamsevents FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998