1. Network Examples Distance to schools in Gambia Puerto Rico Streams Determine water availability for Nuclear Reactors in Russia Invasive fish moving “up stream”

2. Gambia

4. “Hydrology”/Stream Paths Fill Sinks Find direction Find Accumulation SetNull(“Accumulation”<Desired, ”Accumulation”) Stream Feature Make a network?

5. Fill Sinks

6. Direction

7. Flow Accumulation

8. Null Non-Stream Pixels SetNull("Accumulation"<10000,"Accumul ation")

9. Stream To Feature

10. What happened here?

11. Goes “straight” through lakes

12. A stream network?

13. Puerto Rico Streams

14. Missed Connections

15. Be Careful with “Near”

16. Islands and Channels

17. Natural Earth: Oregon

18. Stream Ordering

19. Stream Order

20. Gauge & Tidal Stations Gauge Data: USGS –Flow at a point on a stream/river Tidal Stations: NOAA –Tide and/or current at a location

21. Hydrologic Unit Codes (HUCs) http://water.usgs.gov/GIS/regions.html

22. Hydrologic Unit Codes

23. Sub-Catchments

24. Lakes

25. National Hydrography Dataset NHD http://nhd.usgs.gov/

26. Next Steps? Create a stream network –Combine streams from multiple rasters –Compare the accumulated pixels to gauge station measurements Create watershed –Point along the stream can be a “pour” point Create lakes? –Constant elevation above the “pour” point Get other software?

27. HEC-RAS

28. Hydrologic Flow