Tucked into the Sierra Foothills, Sly Park sits at 3,500 foot elevation. The lake is approximately one mile wide and two and a half miles long.   It offers swimming, boating, fishing, camping and trails for hikers and equestrians.  Sly Park came into existence went James Calvin Sly settled into the area in 1848.  Of course it wasn’t named Sly Park back then, as it was a much needed stop over for settlers traveling the Mormon Emigrant Trail.  After a change in ownership and then the passing of the new owner, his son Park Stark took over operating the ranch which consisted of cattle, dairy, one hotel and a store.  Hence the name Sly from Calvin and Park from Stark.  It was just over 100 years later when Sly Park became a reservoir and renamed after the death of the individual who worked so hard to see its reality – Walter Jenkinson.

During my search for maps of the trails, I found generalized maps that were readily available which included campsites and trails – but they lack any real detail.  My goal wasn’t so much as providing complete detail as it was to bring life to the trail itself with the use of GPS, photographs and various backgrounds.  In doing so it became a family outing with my children taking part in each trip. 

Now to explain a little about GPS itself.  The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense.   The satellites are solar powered with backup batteries which compensate during a solar eclipse. Each satellite circles the earth twice a day and transmits signal information to earth. GPS receivers take this information and use triangulation to calculate the user's exact location.   To keep the satellites on track each are equipped with small rocket boosters.  Their approximate speed is 7,000 miles an hour. GPS was originally intended for military applications, but in the 1980s, the government made the system available for civilian use. GPS works in any weather conditions, anywhere in the world, 24 hours a day. 

Since I was not very familiar with the tracking feature I decided to make a test run to try out the process with a short trip around town.  This was quite successful and gave me the ability to review the various files generated with the GPS photo link. 

Next I acquired information on the trails in a current and proposed format.  Using ArcGIS I started with an aerial and overlaid the trail information.  Now it was time for another test run but this time at Sly Park.  I felt a second test run was appropriate as the terrain around town was quite different from Sly Park and we would be adding vegetation/forest into the mix.  Captured below is the first live test run.  The yellow symbols indicate tracking points and the red indicate a GPS photo link is present. 

Again a success!  After processing the points and photos I brought both into ArcGIS, then by simply hovering over one of my photo points a thumbnail photo would appear.  If I clicked on the point then the photo appears with complete photo details.

Even without ArcGIS I could view an overview with photos showing up in numerical sequence.

By clicking on one of the photo links an enlarged photo is brought up along with all the point position information and photo details. 

Sly Park Trails

GPS Tagged Photo : DSC00387_tag.jpg

Now I was ready for the complete trip around the lake.  This time I took the Garmin 76 and a Trimble Geo XT to experiment with the accuracy.   Halfway through I experienced difficulty with tracking using the Geo XT and had failing batteries on the Garmin.  Ultimately I had to make a third trip to repeat the final leg of the loop.  Below are the results.  The larger symbols represent GPS photo links while the smaller symbols represent tracking points.

Overall, after the bugs were worked out everything went smoothly, I was able to produce a very nice map complete with photo links.  Also, as I mentioned in my introduction my daughter was so impressed with this that she asked for extra maps to take to school.

Although this project covered an area of known location it would be extremely useful when exploring areas that you are not familiar with.  This was my intention after completing the loop around the lake but weather just wouldn’t permit it.  The problems I encountered were weather, poor planning on my part by not having extra batteries, additional steps required for linking GPS photo software with Trimble GeoXT, obtaining the correct time for linking photos and setting the tracking interval too fast.

The next time I would definitely explore an area more remote.  The added benefit to this experience was the involvement of my wonderful children.