We were recently at Yachats --pronounced “Yaw Hots”-- on the coast and our morning walk to town for coffee took us along a footpath that is a portion of the historic “804 Road” (more on the 804 road below).
Along the trail there are rebars marking the right-of-way which were set in this 1987 survey. Most are in coastal death brush that I’m not that ambitious to wade through, but a few of the rebar are easy to spy. It’s been a tough 27 years for these monuments:
Which begs the question, how long do rank and file rebars, pipes or iron rods last along coastal areas? Do they rot as rapidly underground as the exposed portions shown above?
--------------------------------------------
The 804 Road has an interesting history in this area and in 1985 a case over its existence and validity as public R/W went to the state court of appeals, which affirmed that the road, although unused as such for decades, was still a public right-of-way. Much to the chagrin of the landowners who hadn’t acknowledged its existence when they built their humble ocean view dwellings along the bluffs.
The following slide show from the Lincoln County Legal Counsel is an excellent account of the history of the road, surveys and court cases.
To get the slide show to work properly on my computer I had to go into the IE web browser “compatibility view setting” and add the web Lincoln.or.us site to the compatibility view website list.
804 Road photos from last month
804 in front of our motel (the beach was the road in this segment near the 7 mile mark):
804 along the bluffs:
Humble little house inland of the 804 road:
View to the south of Cape Perpetua from around the 9 Mile mark of the 804:
View from the top of Cape Perpetua looking further south. Surveying on the coast is a bitch, or so the locals would lead you to believe...
The wear is common from a few tenths underground to the top that lies above ground around here along water edge of lakes and bayous.
It will eventually wear to a sharp point.
Most of the rod that is below that grade will last a very long time.
Many will become subject to gravity and in the wet conditions without some anchor like a sizable cap or crossbar will sink into the ground making it hard to be found years later (the deeper you dig the more water fills the hole).
Larger pipes and rods will do the same.
Some alloys will last better.
😉
Early in my career I worked in White Rock, British Columbia - a beach front community. I don't recall any particular problem with bars corroding, but the bars used are all galvanized, per statute.
In Oklahoma we have a lake and surrounding area known as the "Salt Plains". Pipes and rebar don't last 20 years in the salinity. The BLM did a lot of work up there in WWII (it was a military ordnance testing site). Their "one inch iron pipes" are probably all gone. We retraced a number of them in the early nineties and all we could find was a 1" vertical column of iron oxide in the surrounding silt. It did provide a good signal for a pin-finder however.
When I was working for another firm in the late '80s one of the other crews worked on a job for BLM on the coast in Marin County, CA. BLM provided 2"x30" Berntsen stainless steel split-bottom pipes with bronze caps for marking the corners. I don't know what those pipes cost back then, but today they're around $70 apiece. They should hold up well in most soils, though.
Old benchmarks in South Louisiana monumented by the USC&GS are copper-clad iron rods with brass/bronze discs crimped on. Nowadays they're stainless. I don't know how well the old marks have withstood corrosion, but the surface marks still exist when not disturbed.
One thing I wish I had done differently here in Southwest coastal Florida, is to use glavanized pipe instead of 5/8" rebar. One of the original surveyors around here, Carl Johnson (no relation), used that and I see them in near pristine condition, even today. I would probably use a different cap though, as they put a plastic cap that ends up flush with the top, inside diameter, of the pipe. When they disintegrate, you still have a stable position, as the range pole tip slides in.