Developing Benton County topo map
I am in the #Data Collection stage currently.
Overview
About a year ago I did a volunteer "let's GPS the weeds" day and was dejected to find the Benton County Soil and Water people have a dozen or so Garmin eTrexes with NO MAPS in them! They cannot afford Garmin maps since they only use these on rare occassions.
So I decided to try to build a custom map for Benton county.
Intended users
- people doing conservation and habitat restoration work
- hikers and mountain bikers
Desired features
- Contours
- Roads: county, McDonald/Dunn forests
- Parks: federal, state, county, city
- Trails in parks
- Land cover- major vegetation polygons
- Hydro- creeks, rivers, ponds, lakes
Data Collection
Points of Interest
I will want to generate a POI file from point data.
ORGNIS - filter a subset of the Oregon Geographic Names database. This data set is notoriously inaccurate spatially since it's designed for small scale maps.
OpenStreetMap - maybe
Vector layers
Streets - Could use either Benton streets (likely) or OpenStreetMap as the source for this.
Railroads - Benton county
Trails - OpenStreetMap probably has the edge here right now. Corvallis Parks was going to have an intern update their trails in 2011 but I don't think that ever happened.
Parks - Benton and Corvallis each have polygon layers
Land trust - areas that have conservation easements or are owned by the Greenbelt Land Trust.
Hydro - Will probably sort out the poly and line layers. Might want to do a subset of lines (they are very detailed) but that detail might also be desirable for the intended audience. (Conservation efforts)
Aerial / raster layer
The newer Garmins (like my shiny new Garmin 62SC) support a raster layer. I have not tried it yet! Soon!
I intend to include a raster layer with this project, but not just yet.
Elevations
I want to try to develop a contour layer using DEMs.
I have LiDAR for eastern part of Benton County. (DoGAMI data which I got from Benton County GIS by special request) Great data but does not cover entire county, so I need to do some mosaicking.
According to DoGAMI, the western half of the county will be available eventually, at that time I will start over again! For now I consider it just part of the challenge.
Until then I will supplement the LiDAR with other DEM raster data at a lower resolution. There is a statewide layer in FGDB format from http://gis.oregon.gov/ They also have quads. The quads I need are
44123c2 44123c3 44123c4 44123c5 44123c6 44123c7
44123d2 44123d3 44123d4 44123d5 44123d6
44123e2 44123e3 44123e4 44123e5
44123f2 44123f3 44123f4 44123f5
As with the Benton county data, some of the Corvallis data was downloaded from their web site, and some provided directly upon request.
I have various existing contour layers too which I can use for comparisons.
Loading data into PostGIS
Because I am pretty much obsessed with PostGIS right now, I will be loading all vector data into it. I will do raster processing outside of PostGIS, at least for now.
County boundary
ogr2ogr -t_srs 'EPSG:4326' -f PostgreSQL PG:"host=bellman user=postgres dbname=benton_topo" County_Boundary.shp County_Boundary -lco GEOMETRY_NAME=the_geom -nln county_boundary
Cities
ogr2ogr -t_srs 'EPSG:4326' -f PostgreSQL PG:"host=bellman user=postgres dbname=benton_topo" cities.shp cities -lco GEOMETRY_NAME=the_geom -nln cities -skipfailures
Wetlands and water
ogr2ogr -t_srs 'EPSG:4326' -f PostgreSQL PG:"host=bellman user=postgres dbname=benton_topo" wetlands.shp wetlands -lco GEOMETRY_NAME=the_geom -nln wetlands -skipfailures
Rivers
ogr2ogr -t_srs 'EPSG:4326' -f PostgreSQL PG:"host=bellman user=postgres dbname=benton_topo" rivers.shp rivers -lco GEOMETRY_NAME=the_geom -nln rivers
Previewing data
I will use QGIS to build a test map,
I will use Mapnik too as soon as I learn what for. :-)
