1. Cost Path Analysis of Skid Trails Using GIS Laura Heath December 14, 2006 FOR 557

2. Outline Purpose Purpose Location Location Analysis Approach and Obstacles Analysis Approach and Obstacles Results Results

3. Purpose Cost Distance Analysis Cost Distance Analysis Raster analysis that calculates the cost of traveling from one cell to the next based on assumptions specified by the user. Raster analysis that calculates the cost of traveling from one cell to the next based on assumptions specified by the user. Goal: Goal: Determine least cost paths for skid trails in logging operations. Determine least cost paths for skid trails in logging operations.

4. Best Management Practices Limit the crossing of streams Limit the crossing of streams No cutting within a 50 ft. buffer around streams and bodies of water No cutting within a 50 ft. buffer around streams and bodies of water Skid trail distances from water: Skid trail distances from water: 50 ft with slope <10% 50 ft with slope <10% 100 ft with slope >10% and 10% and <30% 150 ft with slope > 30% 150 ft with slope > 30% Landings should be flat and well-drained Landings should be flat and well-drained Use existing roads/trails as much as possible Use existing roads/trails as much as possible

5. Approach Obtain necessary information: Obtain necessary information: Roads Roads Tax parcels Tax parcels DEMs DEMs Hydrography Hydrography Edit data to match with orthophotos Edit data to match with orthophotos Vector Data Raster Data Cost Surface Cost Distance Cost Path

6. Location Sexsmith Lake in Davenport, NY Delaware County

7. Step 1: Find location of landing Slope ≤ 3% Slope ≤ 3% Within 100 meters of road Within 100 meters of road Intersecting the road Intersecting the road Not within 50 meters of a body of water Not within 50 meters of a body of water Located within the harvest stands Located within the harvest stands

8. Step 2: Erase Hydrography Buffers from Harvest Stands Step 3: Convert DEM to Percent Slope Classes blue: >30% pink: 10-30% purple: 5-10% green: <5%

9. Step 4: Create Concentric Polygons Within Harvested Stands

11. Step 5: Convert to Raster Spatial Analyst Toolbar → Convert → Features to Raster Spatial Analyst Toolbar → Convert → Features to Raster Slope (%) Slope (%) Concentric polygons (distance from edge) Concentric polygons (distance from edge) Roads (ID of 1) Roads (ID of 1)

12. Step 6: Reclassify Change values of cells to reflect cost of travel Change values of cells to reflect cost of travel Concentric polygons: Concentric polygons: -300 → 1 -300 → 1 -250 → 2 -250 → 2 -200 → 3 -200 → 3 -150 → 4 -150 → 4 -100 → 5 -100 → 5 -50 → 6 -50 → 6 NoData → 7 NoData → 7 Slope: Slope: 0-5% → 1 0-5% → 1 5-10% → 2 5-10% → 2 10-30 → 5 10-30 → 5 >30% → 10 >30% → 10 Road: Road: ID 1 → 1 ID 1 → 1 NoData → 50 NoData → 50

13. Step 7: Overlay Rasters to Create the Cost Surface GIS Help says to use Weighted Overlay Tool GIS Help says to use Weighted Overlay Tool I used the Raster Calculator in Spatial Analyst I used the Raster Calculator in Spatial Analyst [concentric polygon] + [slope] + [roads]

14. Cost Surface

15. Step 8: Create Cost Distance Raster The cost raster was created using the cost distance tool The cost raster was created using the cost distance tool

16. Cost Distance Raster

17. Step 9: Cost Path Calculates most efficient pathway given a destination, cost distance raster and cost backlink raster. Calculates most efficient pathway given a destination, cost distance raster and cost backlink raster.

18. Results

19. Questions?