High Uinta Backcountry Guide
Paul Craig
John Newton
* Every aspect of this project was done
jointly from start to finish, working
separately on adjacent computers dividing
the work as we went along and coordinating
our efforts. The first half of the paper was written by
John Newton and the second half by Paul Craig.
Introduction
The objective of our project was to create a GIS system of user friendly maps of the High Uinta Wilderness area. These maps give hikers, fishermen, and the like a guide to streams, lakes, and other features of the High Uinta Mountains. The following paper describes three major themes we used in GIS to achieve this. These themes are; Data Collection, Data Manipulation, and Creating New Features and are discussed at length in this paper.
Data Collection
Digital Raster Graphics (DRG)
At the onset of our project we knew that we wanted some form of topographical digital maps, but we did not know in what forms they were available or even what a DRG was. Through some research we found that USGS has made available 7.5 minute quadrangles in digital raster format. These are scanned images of the U.S. Geological Survey of standard series topographic maps. The images are georeferenced to the earth in the Universal Transverse Mercator projection. They are available in 1:24,000 (7.5 minute), 1:100,000 and 1:250,000 scales. We needed the highest resolution possible to allow the hiker to identify the natural features on the map and to enable us to calculate trail distances with some degree of accuracy. For this reason we chose to use the 24k resolution maps. These images come with the map collar. As a result the images look like those shown in Figure 3. This problem will be addressed later in the paper. We obtained the DRGs from the Merrill Library. They have all the DRGs for the nation. They are available, with a little persuasion, for students to check out for two hours at a time.
National Elevation Dataset (NED)
In
order to attain a three dimensional look we added NEDs to our maps. Prior to this project we did not fully
understand what the NED was nor how to obtain it. We downloaded the NEDs from the The National Map Seamless Data Distribution
Center provided by USGS (http://seamless.usgs.gov/). The process
was relatively simple and self explanatory (see Figure 1). These images were placed on our map with
fifty percent transparency to add the three dimensional look we desired. Following is a brief description of what the
NED is and how it is created.
The NED is created by USGS.
According to USGS the “NED is
designed to provide National elevation data in a seamless form with a
consistent datum, elevation unit, and projection. Data corrections were made in the NED
assembly process to minimize artifacts, perform edge matching, and fill sliver
areas of missing data.” The NED is
derived from Digital Elevation Models (DEM).
DEMs are also produced by the USGS.
They are an array of elevation values sampled at regualarly spaced
intervals. All DEMs are sampled using
the same methods and are in raster format.
The 10m DEMs (highest resolution currently available) are sampled at 10m
intervals, the 30m DEMs at 30m and etc.
NEDs are assembled using 10m resolution DEMs where 
possible. After the filtering process, which reduces
line distortion and provides other additional benefits, they are resampled at
one arc-second resolution (approximately 30m resolution). USGS had availble for our area 1/3 arc-second NEDs, but due to the size of the
files we were unable to use them in our project. Instead we used the one acr-second NEDs.
Digital Line Graph (DLG)
For our project it was necessary
that we have hydrographic features such as streams and lakes and also trails to
display on our map. We were unsure how
to obtain this data. We learned that
USGS has digital representations of cartographic information called DLG
data. DLGs are derived from 7.5-minute
topographic quadrangle maps and other sources.
They were collected as part of the National Mapping Program. We obtained our data from the Utah Automated
Geographic Reference Center (AGRC). They
converted their data from the USGS DLG files to ARC/INFO format. We were able to obtain roads, lakes, stream,
and springs. In addition we obtained
shapefiles of state boundaries, wilderness boundaries, hospital locations, and
weather stations from AGRC (http://agrc.utah.gov/agrc_sgid/sgidlib/shpindex.htm). We obtained our trail data from the road DLG
files, which include both roads and trails.
We downloaded the NLCD at the same
time we downloaded the NEDs from the The
Figure 2. NLCD displayed with stream DLGs
Data Manipulation
Topographic Map
The topographic map used in our
project was derived from forty-six 7.5-minute quadrangles. As mentioned previously they are scanned
images of the original paper maps in a digital raster format. The collars of the maps were also scanned as
part of the image. When combining the
maps an image similar to the following image is generated.
Figure 3. Original DRG .tif files displayed in
ArcView
Upon inspecting the image one can see that the map collars are not only retained, but that they also overlap and cover a portion of the adjacent map. In this format the maps are difficult to use. We needed to devise a way to remove the collar. We found a tool called a clipper on the Geocommunity website (http://data.geocomm.com/drg/).
This tool (shown above) is an
ArcView tool. After downloading the tool
and installing it we imported all our quadrangles into ArcView. Then we simply clicked on the DRG
clipper. It prompts you to select a
projection (UTM in our case), a datum (NAD 27), and asks if you want to recode
the cells outside the map area to 255 (we clicked “yes”). It then created new grid files of our maps
with the collars removed. These grid
files are saved in the same location as the original data. For this reason one cannot clip DRGs from a
closed CD because the clipper cannot store the new data on the CD. The data must therefore be copied to the hard
drive.
We imported the new grids back
into ArcView. There were still some
regions that overlapped. These regions
were assigned a value of 255 by the clipper and were colored black. A sample of the imported grids are shown
below.
The make clipped DRG
overlap transparent tool came with the DRG
Clipper tool. This tool makes the
black regions transparent, so the DRGs appear as one image. Unfortunately the tool didn’t work. But because we knew these cells were assigned
a value of 255 we were able to change these cells to a transparent color in
ArcMap.
The next problem we encountered is
that when the DRG Clipper creates a grid file it does not retain its coordinate
system.
This made it impossible to project
the topographical map accurately with our other data. We therefore had to add the coordinate
system back in. This is done in ArchToolbox in the Define Projection Wizard as illustrated
below.
The coordinate system had to be
defined for all 46 maps separately. It
was also important that we assigned it the coordinate system it had prior to
the clipping in order to maintain the integrity of the data. It is interesting to note that all of our
data coordinates, except for the DRGs (which were in NAD27), were in
NAD83. Fortunately ArcMap is able to
project data with different coordinates onto the same page with accuracy. As a result we did not have to project the
data to a different coordinate system.
Organizing Data
Geodatabases and
Feature Data Sets
The data for our project is
divided into counties. Our area of study
contains part of the following counties:
Wasatch, Duchesne, Uintah, Dagget, and
Grouping Layers
Our project contains 86 layers of
data. This many layers are very
difficult to work with. Waiting for the
map to refresh wile deactivating or activating layers becomes very
tedious. To solve this problem we
grouped our layers into 16 different group layers (shown at right). By doing this we were able to turn on and off
a group of layers at one time. For
example now we can turn on or off all the topographical maps at the same
time. This made our data much more user
friendly. The process of grouping layers
is quite simple. Simply highlight
several layers in the layer display, right click, and select “Group.”
Activating Layers at Defined Extents
Our project consists of
approximately 700 MB of data. Even after
grouping our layers we still have 16 grouped layers to turn on and off. Turning on and off layers with this much data
takes a great deal of time for ArcMap to process. However, leaving all the data on makes the
map very difficult to view. With all the
layers turned on at full extent our area looked like a mess of blue and grey lines. We decided that at full extent it was never
necessary to have the topographical maps, trails, or trailhead names tuned
on. And that when zooming in close on
the topographical maps it was unnecessary to have the NED and NLCD turned
on. As a result we defined the extent at
which these layers would turn on and off while zooming on the map. This is defined in the general tab of the
layer properties (see screen capture below).
The only difficulty lies in
selecting the appropriate extent (max and min scale) at which to turn on and
off the layers. This was achieved by
trial and error.
The process for turning label
names on and off at different extents is slightly different. Go to the labels tab of the layer properties
window and click on “
The figures below Illustrate what
our project looks like as one zooms in and layers turn on and off.
1 2
3 4
5 6
Creating new features
There were a number of features that weren’t available to us for downloading. So we decided to create our own new features to help the map be more user friendly and make the data easily accessible. This was an easy thing to do, and as we got further into it we realized more and more tools that were available.
Trailheads
Trailheads were the first features that we created. We had all the trails on our map but as we got further into the project, we found that the 7.5 minute quadrangles that we used for our map had no apparent trailheads on them. We wanted to make the map user friendly for hikers so we decided to see what type of information was available that hikers and campers might want to have. We found a paper map of the High Uintas and found a lot of good information that would be beneficial for our user friendly map. Not only did it have the locations of the trailheads, it also told us what types of services were available at each specific trailhead. With this information we decided to try to see how GIS could help us organize it.
To do this we had to create new feature classes. The process for creating a new feature class is done inside of ArcCatalog. First we navigated to the geodatabase that we created for the project, right clicked on it and clicked, New, then Feature Class… and named it Trail heads. Because the new Trailheads feature class that we created was going to have point features in it, we needed to define its geometry as a point feature. By doing this, it enabled us to create new points within this feature class. Another thing that we wanted to do was to organize information that we found on our paper map in the attribute tables within each respective trailhead point feature. To do this we had to create new fields in the attribute table. While in the same screen that we configured the geometry type of the new feature class, we added these new fields by clicking on the tabs to the left of the field names that were blank. We created five new fields that we had information on; trailhead name, drinking water, bathrooms, information stations, and developed campsite. With the new feature class created and the new fields, we had to create 28 new trailhead points and input the information into the attribute tables. Creating the trailheads was a very tedious and time consuming task. We took the paper map that we had and zoomed in on our GIS map and manually created the trailhead points. This is done inside the editor toolbar in ArcMap. Under task in the editor toolbar we selected Create New Feature and as our target we selected our Trailheads feature class, so that GIS knew where to put the new point features. After creating all the trailheads, we had to input the information into the attribute tables of each trailhead. While we were still in the editor mode we went into each trailhead attribute table and typed the information for the new fields that we created earlier. For this we put YES or NO as the value of the field to show if the service was available or not at that particular trailhead. Once this process was complete, the user of the map could click on the identify icon in the tools toolbar, then click on one of the trailhead symbols on the map and the Identify Results screen would come up for that trailhead which has the information in it. The screen capture below shows an example of the Uinta trailhead that we created, with its Identify Results screen.
Another thing that we did was to go through all the major trails that we downloaded from AGRC.Utah.Gov to make sure that they matched up to our 7.5 minute quadrangle trails. While we were creating all the new trailhead point features, we checked to see if the trails were updated. There were several that weren’t so we created them by tracing over the 7.5 minute quadrangles trails as new line features.
Another feature that we created to help us visually organize our map was a new state boundary. All the data that we collected and used in the map were organized in counties. We were only interested in the High Uinta wilderness area which has five different counties. So there was a lot of extra data that we had to work with. We only wanted to have the lakes, streams, trails, etc… show in the wilderness area and not in all five counties. We started trying to delete all the trails that weren’t in the wilderness area, but this would have taken a very long time to do this to all of the information. So we decided to create a new polygon feature called UtahStateBoundary. The screen capture below shows this new polygon feature. To do this we again had to create another new feature class within our working
geodatabase. This was done the same way as before with the trailheads. But this time we needed to define its geometry as a polygon feature instead of a point feature. Once we created our new feature class we created the new polygon. This was done once again in the editor tool in AcrMap. Again we set our task as Create New Feature, but this time we set the target as our new UtahStateBoundary feature class. We activated the original state boundary that we downloaded as well as the wilderness area on our map and traced the new polygon that cut out the wilderness area. This was done with the sketch tool in the editor toolbar. We placed this new Utah state boundary over the top of the lakes, streams, trails, etc… so that these layers were only shown in the wilderness area.
Weather and Sunset Information
Another feature that we wanted to have accessible on the map
was information about the weather, sunset and sunrise. We decided to add
hyperlinks to certain points that would send you to websites that have this type
of information. To do this we needed to create a few new point features that
people could click on to go to these websites. We decided to have two general
points that would have links to general weather forecasts for
The two new points that we created were created in the same manner as the trailheads except for the feature class was named Information. To create the hyperlinks for the points that we had we had to click on the Identify tool in the toolbar, click on the information points and the Identify Results screen comes up as shown in the screen capture below. Right click on the point and then Add Hyperlink… There you have the option to either add a URL or a document.
We added the following two web pages to our information points.
The way that these websites are accessed by the user is with
the Hyperlink tool. 
With that tool you can click on the point
feature that you want to access the websites from and this Hyperlinks screen appears and you can choose which site you want to
jump to.
The other website that you can access from the weather station points is shown below.
This website has information on the average monthly temperatures and precipitation over the last 30 years for the specific area in
question. We thought that this would be good information for people who were planning camping or hiking trips and wanted to know
what to expect the weather to be like.
References:
http://nrwrt1.nr.state.ut.us/quads/
http://agrc.utah.gov/agrc_sgid/sgidintro.html
http://atlas.utah.gov/MetadataExplorer/explorer.jsp