Mapping Fripp Island, South Carolina with OpenStreetMap (OSM)
In December of 2010 I saw a piece about OpenStreetMap in the Wall Street Journal. I will hereafter refer to it as OSM. A full description of OSM on Wikipedia can be found at http://en.wikipedia.org/wiki/OpenStreetMap. Essentially, OSM is a collaborative project to create a free editable map of the world. What the WSJ article said was that updating in certain parts of the world had been going on for some years but in the USA, except for the big cities in America, not much had been done.
I’ve always loved maps and I was curious to see what Fripp Island looked like on OpenStreeMap. I was delighted to find that it needed help badly. Most streets did not line up with the satellite photos, many were misnamed, points of interest were unnamed and there was a lot of data just plane missing. In other words, I had a project if I wanted to get into it. I did.
The map database in OSM can be edited through your browser with an editing tool which OSM provides. Through trial and error and use of the OSM Help Center to post questions I gradually got going. My first steps were to realign streets to make them line up with satellite photos. I spent a few days doing this but I could see this would only get me so far. Often the foliage in satellite imagery obscured the view of the street. The only way I could get all the streets aligned was to make gps traces and then upload these traces to OSM. From the traces, I could then trace the path actually taken by a street or trail whether I could see it or not. I needed a GPS unit.
Again the OSM Help Center was a great source. Some helpful people recommended the Garmin eTrex Legend HCx . Not cheap but it has a very sensitive gps receiver (good in heavy foliage for example) and good battery life, I got one from an on-line store and started doing traces. The first traces I did were of the small trails between properties to the beach from various roads paralleling the beach. I started at the south end of the island, walking with my GPS unit getting a trace for each one. There are 32 of these and here is a section of the OSM map showing some on the north end of the island.
The public beach accesses are the red dotted lines going out to the beach. Some are labeled. If you like, you can go to Open Street Map using this link:http://www.openstreetmap.org/?lat=32.32208&lon=-80.46806&zoom=15&layers=M.
Lots more to do. In some cases, whole neighborhoods were so badly represented I found it easier to do gps traces of all the roads in those areas and replace the original TIGER maps. Also, lakes, ponds were not aligned well. I added parks, trails, tennis courts, community swimming pools and lots of buildings. Here is a section in the middle of the island containing the tennis courts, some pools, restaurants etc.
I walked the beach at high tide and low tide to be able to capture the approximate current shoreline. The OSM rendering of the island (what you see in the “View”) shows the shoreline approximately as it existed at high tide on December 30, 2010. I tried to be sure that all the Points of Interest on the island were shown. I added as many “tags” as possible to roads, buildings and POI’s. As I understand it, these tags help the rendering programs to show these features more accurately.
Why, you are wondering, would I want to do this. Well, mostly just for the fun of doing it, of creating something. I love maps. I like walking around the island. It was winter and gave me something to do. Several hours on most days over a span of several weeks. I also like the idea that OSM data will be used more and more in mapping software and when someone looks at Fripp Island using OSM data, they will see what really exists. The roads, trails, pools, parks, golf courses, restaurants, and other amenities will be where they are supposed to be. In a nutshell it was fun. I can also say that none of the other on-line maps that I have looked at are as accurate as mine. That includes Google Maps which I love and use often but it has many inaccuracies. Google is now allowing updates from people like me and I have made some but the process is much slower than with OSM.
Take a look at OpenStreetMap in your neighborhood. Go here http://www.openstreetmap.org/ and then type in your zip code or city and state in the search box and GO. Maps are fun.