"X" mark in a manhole

grinder, run off an invertor from your vehicle..

Drill a hole (1/16") and plug with a copper nail pounded flush.

Drill it in the lid so you can adjust your closure as needed. 😀

I'm always reluctant to leave anything on a manhole rim other than temporary control, because when the street gets rebuilt and the rim reset, the mark will persist but it won't be in its original position. (It might not even end up on the same manhole.)

That said, if I had to have an X I'd use a die grinder with an abrasive wheel. If a smaller mark will do, a tungsten carbide center punch is the quickest way to go.

perhaps after grinding the "x" marking the spot, grind two index marks into the lid & rim (not 180° apart) to check if later the rim had been reseated/rotated.

> I'm always reluctant to leave anything on a manhole rim other than temporary control, because when the street gets rebuilt and the rim reset, the mark will persist but it won't be in its original position. (It might not even end up on the same manhole.)

4 MAG nails or PKs as straddles will work, until the road is repaved. Better than the cross cut in the rim that winds up turned from it's original location...

While he's at it might as well put a permanent Bench Mark on the truck bumper 😉

How permanent? Latex paint would last a while.

Cold chisel is what we use.

Derek

> perhaps after grinding the "x" marking the spot, grind two index marks into the lid & rim (not 180° apart) to check if later the rim had been reseated/rotated.

Perhaps I misunderstand your idea, but it seems to me that this won't work. The relationship between the lid and rim will change every time the lid is disturbed, and in any case won't conclusively disclose movement of the rim itself, as would occur with road reconstruction.

I don't mark manholes.

I call for point in manhole lid and give a witness reference to the center of the manhole.

0.02

If temporary is ok... Paint marker on rim.

Pop the lid and use a hacksaw to saw an "X" in the rim - done a jillion that way. Or use a die grinder or Dremel tool with a very fine abrasive wheel. Or drill a 1/8" hole in the rim and fill with paint.

What is the purpose of the X? If it is to mark a property corner I definitly would not set an X on a MH lid as they are far from permanent. Either set straddles about 1-2 feet away or set a reference monument somewhere close.

Nothing faster than a chisel mark.

The rim of a sanitary sewer manhole makes a good benchmark when running levels or if the corner falls in the manhole cover, the X can be called for as the witness to the corner.

> The rim of a sanitary sewer manhole makes a good benchmark when running levels or if the corner falls in the manhole cover, the X can be called for as the witness to the corner.

As noted above, anything on a manhole rim must be considered temporary. When the road gets reconstructed, the rims are relocated -- sometimes at the same manhole and sometimes not, but almost certainly not in the same position as before.

In regards to an X being placed on a manhole as a property corner, what are the odds of someone running a string line from it to a rear lot pin to mark a property line after it has been opened and replaced in a different position. I would say slim to none but I have run across some pretty stupid home builders. You don't need all of the corners to locate a form for a new home or building so in that regards my firm notes that corner falls in manhole lid. If you assume it cant happen then it probably will.

Thanks!!!! We have a job to report elevations, temporary use, of 95 manhole rims. Thought there may be an easier way than the old chisel mark. FEMA's proposing on new FIRM maps to remove oceanfront lots from a "VE" to an "X"..............