At the start of this lab I had the freedom to choose my own
research question. I decided to determine the best location to build a cabin in
Sawyer County, Wisconsin. This question appealed to me because after a long
hectic week of finals, a nice secluded cabin would be ideal. With that being
said, this research can help hardworking families or individuals create a
home-away-from-home that provides a quiet environment to relax and enjoy the
outdoors. Criteria for this cabin includes…
Location on
a lake
Near a
forest or national park
An isolated
location
At
least 5 miles from nearest city
About
2 miles away from any major roads
Located near
a hospital in case of an emergency
These parameters would create the best area for a nice-get
away cabin.
Data
Sources
Luckily, the data needed to complete this project was found
relatively easily in the Wisconsin and ESRI geodatabase. The data necessary to
complete this project included Wisconsin county boundaries, lakes, county
forests, U.S. parks, hospitals, cities, and major roads. Sources of the data
are as follows
County Boundaries: Wisconsin
DNR 2014 Data
Lakes: ESRI 2013 USA Data
County Forests: Wisconsin Forest Inventory &
Reporting System (WisFIRS)
U.S. Parks: ESRI
2013 USA Data
Hospitals: Geographic Names
Information System (GNIS) Hospitals
Cities:
Wisconsin DNR 2014 Data
Major Roads: Census 2000 TIGER/Line files
The data I retrieved concerned me in a few ways. For
starters, I am concerned about the cities data. I am curious as to what the
data determines a city to be. Is it based on area or population? I feel as
though Sawyer County may have more cities than portrayed which may alter the
findings throughout the project. Initially, I was concerned about the water bodies
shown in the map. Originally, the layer had several rivers/streams, along with
some rather small bodies of water. After looking through the attribute table, I
realized the data had all types of water bodies. After conducting a simple
query, I was able to select only the lakes to create a “lakes” layer. Because
most of my data is rather static, I was not concerned with the accuracy or
chance that the data has changed since collected.
Methods
Before starting the project, I first made a database
connection to both the ESRI 2013 geodatabase and the Wisconsin DNR geodatabase.
This allowed the process of selecting and adding the necessary layers to the
map much easier. The process of my project is shown in Figure 1 as a data flow
model.
To begin, in ArcMap, I created a blank document and
added the Wisconsin county boundaries. From here, I selected Sawyer County and
exported it to create a new layer in the map. Once Sawyer County was a new
layer, I then added the needed data layers from the two geodatabases to the
map. These data layers included the lakes, county forests, U.S. parks,
hospitals, cities, and major roads layers. I then clipped the each data layer
with the Sawyer County layer to have only the data within Sawyer was shown.
This allows the software to run much faster because it narrows the data being
geoprocessed to those only within Sawyer County’s boundaries.
To begin the narrowing process, I put a union
between the county forests and U.S. parks layers. I then put a 1 mile buffer
around them because I want the cabin to be within that distance from a forest. I
then dissolved the buffer to generalize the data. I then put a buffer of 100
feet around all the lakes within Sawyer County. I did this to ensure a lake
front property. I then intersected the lake buffer layer and U.S. Parks/county
forests layer. This allowed me to narrow down the locations to lakes near a
forest. To ensure a somewhat close proximity to a hospital, I put a 20 miles
buffer on the hospital layer. I chose 20 miles because that is a reasonable
driving distance in the case of an emergency. If the buffer had been smaller it
would have put the location closer to cities or major roads. By taking the
hospital buffer layer and the lakes and pakrs/forest intersect layer and
applying another intersect, I could see all of the desirable locations for a
new cabin thus far.
Next, I started to take out the areas I did not
want. I put a 2 mile buffer around the major roads layer to ensure a quiet
location without noise pollution from traffic but still close enough for easy
accessibility. I then determined the distance from a city would be 5 miles. I
assumed that any closer would bring more noise and chaos to the area. I then
but a 5 mile buffer on the city layer. I then took the two layers containing
the areas I do not want and put a union between them.
Now that I know the areas near roads and cities, along
with the desirable traits of a cabin location, it is time to take out what I do
not want. To do this, I performed an erase between the desirable layer and the
undesirable layer. This left me with the lakes near forests and a hospital but
away from major roads and cities.
However, after looking at the final product I realized
my data and answer did not make any sense. If I had left it the way it was, it
would have shown that a desirable location for a new cabin would be in the
middle of a lake. To solve this problem I erased the original lakes layer from
the output. This left me with just the areas along the lake that were near
forests and hospitals and a desired distance from any cities or major roads.
 |
| Figure 1: Data Flow Model |
Results
As a final product, I decided to create two separate maps. The first map shows the desired areas in Sawyer County that meet the specified parameters (Figure 2). The second map, though very similar, shows the buffers created in the process to show the reasoning behind the highlighted desirable areas in both maps. Also, in both maps, I provided a small locator map of Wisconsin along with a large-scale map of the top locations. Large-scale Map #1 shows the locations on Nelson Lake in the Northwest corner of Sawyer County. Nelson Lake has a lot of possible locations for a cabin which makes it a marketable location. Large-scale Map#2 shows the locations on Spider-Clear Lake in the Northern region of Sawyer County. This lake is smaller compared to Nelson Lake which can come with both benefits and disadvantages. This lakes also has a substantial less amount of land to choose to from when deciding where to build a cabin.
 |
| Figure 2: Top Cabin Locations in Sawyer County, Wisconsin |
 |
| Figure 3: Top Cabin Locations in Sawyer County, Wisconsin showing criteria |
Evaluation
I felt this project did a good job in showing the new skills
we have learned throughout the semester in GIS I. If I had to repeat the
project, I would add some criteria to it. I am interested in finding out
whether or not the areas found desirable are DNR managed land or already owned
by others. I could do this by adding the DNR managed land layer in found in the
WiDNR geodatabase. Some challenges I faced involved the buffers throughout the
project. Some of the preferred distances would have landed me with no locations
to choose from. I had to change the buffer distances to ensure a desirable
location would result. Something I would like to do in the future is expand the
area of interest to the entire state of Wisconsin.
No comments:
Post a Comment