Transcript Trails in the Santa Monica Mountains NRA

Trails in the Santa Monica
Mountains National
Recreation Area
Liz Baumann, December 2015
CVEN 5381 – Intro to GIS
Trails in the Santa Monica
Mountains NRA (SAMO)
1. Introduction
2. Objectives
3. Procedures
4. Results
5. Challenges
6. Conclusions
7. Data Sources
Introduction
The Santa Monica Mountains NRA (SAMO):
• over 150,000 acres or ~240 sq miles
• east of Los Angeles; north of Pacific Ocean
• 4 state parks occupy about 1/4 of the area
• elevation: sea level to over 3,000 feet
• over 430 miles of trails
Objectives
Maps with meaningful backdrop layers
Show trails by combination of:
• Trail use (bikes, dogs, or horses allowed)
• Trail difficulty rating (how strenuous)
Procedure
1: establish background layers
2: join trails to non-spatial trail use table
3: add elevation and develop trail ratings
1: Background Layers
Lines:
trails, roads, hydrology
Polygons:
SAMO, state parks, counties, cities, fires
Multiple file formats:
gdb feature classes, shp, web map
Different coordinate systems:
NAD83, NAD27, WGS84
1: Background Layers
1: Background Layers
2: Trail Use
• Assemble non-spatial table:
• one column each for bikes, dogs, horses
• from paper maps, online lists, books
• large in scope => incomplete; State Parks ok
• Join to Trails layer
• Also calculate trail miles and join park name
• Results: 499 trails, 750 km / 466 miles
2: Trail Use
2: Trail Use: Bikes Allowed?
3: Elevation, Trail Rating
• Two Elevation (DEM) rasters
• Added elevation and slope fields to vector Trails
• 3D Analyst “Add Surface Information” tool
• analyzed results, developed formula
• (Z_Max – Z_Min) / Shape_Length * 1000 →
easy, mild, moderate, strenuous, very strenuous
• Added field with applied formula
• Python scripts for attribute management
3: Elevation, Trail Rating
3: Elevation, Trail Rating
Results: Map Layout
Results: Multi-featured Report
• sorted by descending trail rating, miles, trail name
• also shows if bikes, horses, dogs allowed
Challenges
• Python with ModelBuilder
• Data management / scope
• Reports
• Field names change after join => layer files issue
Challenges: New Skills
Managing bookmarks
--
Python
--
Editing metadata
Conclusions
• Trail rating formula is effective
• Reports show multiple features at once
• Useful backdrop layers in geodatabase
Could be even better if…
• trail use complete
• trail rating revisited
• combine trail segments
• extend to other parks!
Data Sources
Note, in reference to various disclaimers given with below data sources, the
data presented in this document should be viewed as a general guide and
should not be used for wayfinding, official or legal determinations.
• ArcGIS Online: Public Trails in the Santa Monica Mountains National
Recreation Area, by NPS. Last modified March 2015.
• SAMO small scale base GIS water quality data from IRMA (Integrated
Resource Management Applications). Released January, 2001.
• The National Map, National Elevation Data: 1/3 arcsecond digital elevation
models for n35w119 & n35w120. As of January 2013.
• Fire perimeters from California Department of Forestry Fire and Resource
Assessment Program (CDF-FRAP). Through July 2014.
• California State Park boundaries, as of March 2012.
• Census Tiger/Line shapefiles, county boundaries as of 2015.
• National Geographic Maps Trails Illustrated #253-Santa Monica Mountains
National Recreation Area (a paper map), 1998.