Wyoming’s NHD and WBD Maintenance and Enhancements

1. Wyoming’s NHD and WBD Maintenance and Enhancements Paul Caffrey Wyoming Geographic Information Science Center (WyGISC) NHD/WBD Stewardship Conference March 29-30, 2012 New Orleans, Louisiana

2. What have we done What have we not done What next Discussion/Questions Overview

4. Dams Gaging stations Diversion structures State Events

5. 1,458 new Dam Events were added that were not originally captured in NHD 56 existing Dam Events were spatially corrected (these dams were originally captured in NHD, but not at correct location/point along NHD Flowline) 90 new Gaging StationEvents were added 24 new Diversion StructureEvents with radio telemetry State Dam/Gaging Station/Diversion Structure

6. GNIS & NHD • Performed a check to locate and correct • Missing • Misspelled • Misplaced • named features for the streams, rivers, lakes and point features in Wyoming

7. GNIS & Hydrographic Features

8. GNIS & Hydrographic Features

9. GNIS & NHD • For the NHD, the task for assigning names to water features using the GNIS was a pretty straightforward process. Unfortunately, discrepancies and errors persist due to: • low resolution GNIS vectors and points and coordinate errors • interpretative mistakes made during GNIS conflation process while creating the hydrographic data.

10. Example: GNIS line vectors

11. Streams: 97 NHD Flowlines (originally unnamed) received GNIS names and ID numbers 129 NHD Flowlines received corrections to their GNIS name and/or ID number 19 are unable to be corrected due to inherent GNIS coordinate errors and other issues GNIS updates made to Wyoming’s NHD

12. Lakes/Reservoirs: 638 NHD unnamed Waterbodiesreceived GNIS names and ID numbers 118 NHD Waterbodies received corrections to their GNIS name and/or ID number 123 WB features missing geometry have been captured

13. Lakes/Reservoirs (cont.): 34 NHD Waterbodies with missing or incorrect GNIS names/IDs are still in need of correction 294 are unable to be corrected due to inherent GNIS coordinate errors and other issues

14. Springs/Waterfalls/Rapids: 206 missing features currently being captured, soon to be added to NHD Point geometry 236 NHD Points with missing or incorrect GNIS names/IDs in need of correction 62 not corrected due to inherent GNIS coordinate errors

15. 151 watersheds (10-digit units) have received an updated HU_10_NAME 52 of these are shared with one or more bordering states and are awaiting coordination 1,309 subwatersheds (12-digit units) have received an updated HU_12_NAME 153 of these are shared with one or more bordering states and are awaiting coordination WBD- Hydrologic Unit Name Updates

16. NHD/WBD Pour Points

17. Primary purpose for creating the True Pour Point features was twofold: • To capture the most accurate geographic location of all WBD outlets/stream drainage points using the 2009 NAIP • To assess the horizontal accuracy and vertical alignment discrepancies between a stream's current pour point location and its WBD and NHD counterpart • Pour Point/NHD average offset distance equaling ~70 meters • Pour Point/WBD average offset distance equaling ~121 meters. NHD/WBD Pour Points

18. 2,327 True Pour Points were placed at the most horizontally accurate/current geographic location of drainage points for all streams at WBD outlets The number of True Pour Points exceed the number of WBD outlets (2,195), due to multiple drainage points from complex stream channels 2,192 NHD Pour Point Events were indexed to the top of all NHDFlowline reaches draining from WBD outlets NHD/WBD Pour Points

21. NHD/WBD Pour Points

24. Acknowledgements- USGS/NRCS NHD/WBD Team Barb Ray, WY Geo-Liaison Wyoming BLM: State Office, Rick Schuler Wyoming State Engineers Office Jason Feltner Wyoming Board of Geographic Names UW/WyGISC Team Pat Madsen, GIS Specialist

25. Discussion Questions