Friday, May 28, 2010

Broken Benchmark

I have gotten into the habit of logging benchmarks when I stumble upon them.  Chaosmanor and I actively went searching for this particular benchmark, mainly because it hadn't been monumented in over 40 years.  A lot can happen in 40 years and to assume that a benchmark, no matter how sturdy or solid it appeared to be back then, will still be in the same place later on is foolhardy.

I think one of the reasons I didn't enjoy benchmark hunting at first is because when I "discovered" benchmarking, I immediately went out and tried to find the closest benchmarks to where I lived, only to come up empty on four or five attempts.  Being a rookie to this particular GPS activity, I didn't know all of the ins and outs at the time.  I'm not saying that I do now, but I understand what to look for and how to look better than I did 6 or 7 years ago.

The first benchmarks I went hunting weren't there, because of the federal government.  The Feds didn't destroy them, rather other agencies probably inadvertently destroyed them, while complying with the American Disabilities Act (ADA).  I had been looking for disks attached to curbs.  When streets had been widened or worked upon, the curbs had to be made wheelchair accessible.  New curbs were laid and the old curbs, which had the benchmarks attached to them were discarded.

In urban or suburban areas, I would suspect that many early benchmarks disappeared because of new construction all the time.  In rural areas, without as much construction, benchmarks tend to last longer, which is why I find most of the markers on my list out in the desert.  The marker that Chaosmanor and I went searching for was out in the desert, so we assumed that we'd find it in the ground where it should be according to the description listed on the benchmark page.

We were sadly mistaken on this account as we found the benchmark, attached to its concrete post lying on the ground.  The benchmark was in the general vicinity of where it was supposed to be, but some kind of construction, or possibly a farmer tilling his field had pulled the post out of the ground.

Because there hadn't been any kind of report on this benchmark in over 40 years, we can only speculate as to when this took place.  We both estimated that it had been several years at least that the benchmark had been in its present condition.  We could find no evidence of any kind of hole where the concrete post should have been in, indicating that several seasons had gone by for enough erosion to have occurred to refill the hole.

I'm going to assume that whoever pulled it out of the ground had one of those "Oooops" moments and didn't want to risk a fine, so decided to leave well enough alone and just disappear back into the desert environment.  With that assumption, the hole would have slowly filled up over the course of a couple of wet winters and there would have been little evidence of where the post should have been in the ground.  The post is about 3 feet in length, so three or more years would have been minimum I think to fill in a hole.  Then again, the person who pulled it out, might have helped it along by refilling the hole.

Overall, the benchmark is in pretty good shape.  It's just not useable the way it is, because it's not in the right spot.  At least with a little detective work, we've been able to piece together a little bit of its history over the past 40 years.

Pictures were taken near the following benchmark:

Profile for Webfoot


chaosmanor said...

That was an interesting Recovery; I've only found one other benchmark like that: completely out of the ground.

FWIW, I filed a Recovery (damaged) with the NGS on April 26th. On May 4th, the NGS declared the Mark to be Destroyed. It can't be found in a normal search of the Datasheet database, now. To find it, one has to ask for Destroyed Marks to be included. This is the first Mark that I've Recovered in poor or damaged condition that has subsequently been declared Destroyed. I wonder if they are making a greater effort to get missing Marks out of the system. If so, I think that that's a good thing.

Lincoln said...

I've yet to go benchmarking partly because there's so many geocaches and waymarking spots in my area to keep me busy, but I might go visit one just out of curiosity. Amazing how many of them still withstand the test of time!