Proper Witness Post Terminology?

[Wintertime]

I want to file some recovery reports with the NGS and want to make sure that I use the correct terminology. A bunch of survey marks along the Wawona Road in Yosemite National Park originally (back in the 1940s) were described as being "near a white wooden witness post."

 

Those wooden posts are long gone, but some survey crew came along at some point and installed concrete and/or metal witness posts. E.g.:

 

 

and:

 

 

Would it be correct for me to say, "The mark is now near a concrete witness post" or "The mark is now between a concrete witness post and a red metal witness post"? I noticed that last year, I included the following information in one recovery report: "WITNESS POST IS NOW A CONCRETE POST APPROXIMATELY 6 INCHES SQUARE AND 2 FEET HIGH." But maybe that's too detailed.

 

Suggestions?

 

Patty

[evenfall]

Patty,

 

You have raised a great question! I am going to answer in a way that may also help others who may be wondering how to approach their own recoveries like this as well.

 

In this case, since you are no longer in Yosemite, you could say something like this;

 

The original wooden witness post was not found. two new witness posts without signs have been placed near the Station. One is a concrete post and the other is a metal post painted red. The metal post is the closer post to the station and the station is situated between them.

 

If you do know the directions and distances or even the post heights, you could simply say something like;

 

The description is adequate with the following updates. The original wooden witness post is not found. A new (or two new) witness post(s) have been placed near the station. A concrete post, 6x6 square which stands 2 feet high is located 7.5 feet southwest of the Station and a metal post currently painted red about 2.5 feet high is 3 feet southeast of the Station.

 

It is cool to know the bearings and distances, even cardinal directions are helpful, but if you don't have a way to check them there are other ways that can help. Any way that a description that can be improved and updated can be helpful, as the world changes and some of the described items can be removed or changed in an area over time. if I am stumbling through the woods and I know I am looking for a couple witness posts and I see them from a ways away, that is an aha moment, especially if I am looking for a Scaled Bench Mark that could be anywhere near by. Triangulation should have coordinates which are more accurate than consumer grade GPS can do so it may be easier, but in the woods without a good GPS signal, perhaps knowing I am looking for a couple posts, one red and one concrete can be super helpful.

 

On the NGS recovery page you can put in up to 15 lines of text. The key to it is just be succinct and descriptive. Please feel free to write as much as is needed, that you feel will help improve the description. If the description is adequate, you do not need to say that, nor do you have to write anything at all, just click the button that said it is found in good or poor condition, and then on the next page mark the button that appropriately defines the Station's GPS usability.

 

In the cases where you do find a replaced witness post, feel free to take a bearing from the post to the Station Mark and a distance between them and add them to the description if it has not been done. All it takes is a compass and a tape measure and it is a helpful addition to the Datasheet. In your photo it shows that the Station could cover with needles and such and so it can speed up the hunt to know where to look if it is covered.

 

There is no standard practice for where to put a witness post. There are schools of thought. Some feel it best to put it close to the station to aid in finding the station, others feel that it should not be too close, but in the vicinity, so as to avoid vandalism to the Station... In either case, and we will see both schools of thought in the field. Either way if we improve the Datasheet the person looking for it will have the most up to date aid to help them find it.

 

One other thing that is helpful is to look on the NGS Datasheet to see if the Latitude and Longitude are scaled. This will define the station as a Bench Mark Station in most cases. (some GPS Station Observations include both Triangulation and Elevation data) If they are, we can improve upon this by adding our GPSr's waypoint coordinates for the station to the description, in NAD 83 ddd.mm.sss format. That suddenly becomes a digital witness post that will be in the datasheet forever. It isn't necessary for a triangulation station however because the coordinates are already accurate to at least a half inch accuracy already.

 

Overall, most Surveyors will appreciate the details, because as you know, sometimes it takes everything there is to help find the station. In 25 years, who knows which details will still be true?

 

Rob

[+PFF]

Evenfall wrote:

 

On the NGS recovery page you can put in up to 15 lines of text. The key to it is just be succinct and descriptive.

 

Hi, Rob:

 

I have found that when the error message LINE TOO LONG appears, I can fix the situation by going back to the text and adding a 'carriage return and line feed', using the ENTER key.

 

I agree with you about being succinct. But does anyone know how NGS officially defines a 'line'? Is it what we would call a 'paragraph'?

 

-Paul-

[Z15]

Since the reason for the witness post is to find the station, it makes more sense (IMO) to describe the mark from the witness post or other objects as C&GS did. [Most land surveying describes the reference from the point which means if you can't find the point you have to turn around the bearings to look, nore time consuming]

 

Such as;

 

It is 5 ft NW of a 4-inch square by 2 ft high concrete post.

 

or

 

It is 1 ft SE of a metal witness post without a sign attached.

 

or

 

It is 1 ft SE of a metal witness post with a sign attached.

 

I see no point in mentioning that the original witness post is gone unless there is nothing else there to replace it. Such as; There is no witness post at this mark.

[Wintertime]

Thanks, Rob and Mike, for the detailed answers. In the future, I will gather distance and bearing information from the witness posts. For now, I'll simply indicate the presence of the post(s) and say "near" or "between." (FWIW, the original reports don't have detailed information, either! They all just say "near." :-) )

 

Patty

[+GEO*Trailblazer 1]

One note.

 

On witness posts that I find down I place them at the point given in the original data sheet.

1 ft.NW of the Station ect.

 

If no witness post is present I make the note no witness post found.

[evenfall]

Paul,

 

What I understand, from people I have spoken with at NGS, is that they have discovered a quirk in the online recovery program. They say you should keep typing until you get to the end of the line. Each line can hold 426 characters and there are 15 total lines.  They ask that you not put hard returns sooner, because you limit your available space. If you need more than 15 lines to re-describe a Station, and it can conceivably happen sometimes, just contact them directly. They may just ask that you email the recovery and they will submit it for you. I wouldn't use a program like Word to rough these out because Word will insert a hard carriage return where ever you set the page to wrap the text. I use a basic text editor and I have it show me word and character count, as well as all the invisible characters so I can see where I put my returns and spaces, then I paste it to the recovery form and tweek it from there.

 

Patty,

 

It was a really good question. I am glad you asked it because it helps clarify what helps a description. I recently recovered a Station that had not really been recovered since 1953. The Power Squadron said they found it 2 years ago but I have my reservations about that. It was a really tough find. Most of the old description was unusable, in fact the reference mark is not findable, as there is nothing left that references the RM. It was poorly described to begin with. The Power Squadron would have had to perform a lot of measuring with tools they would be unlikely to have in order to find it, I had to uncover it from under 8 inches of top soil and cut a 2 inch diameter root that had grown over the top of the Station. There were so many roots in there that there was no way the station had been recovered in less than 2 years. Then all they submitted was that it was found. They entered no narrative entry. Yeah Sure. I used a good bit of 15 lines writing a good description for that Station.

 

Mike also makes a great point. Another Station I recently recovered was a 2nd Order Triangulation Station with 2 Reference Marks, Both of the RM's were set in drill holes in the curb by the street. The Station itself was under 4 inches of sod between 45-50 diagonal feet away from the RM's. simple enough right? There were 2 pages of narrative recovery listed after the station's basic metadata... It was described in so many ways... They measured from a ton of objects all around, some of which were gone, others not. Many difficult ways. Can you imagine a line projected south, 29 feet from the curb which is 17 feet west of a line projected south from the approximate centerline of a sidewalk leading to the entrance of a building across the street? Ok, I'll bite, the building across the street has three entrances. Great. Which? Oh and the Station was 29 feet... South... From the back of a 6 foot wide sidewalk, not the curb. The curb is a funny object too because we Surveyors have many ways to reference from a curb so naturally that starts us to thinking, Face of Curb? Top Back of Curb etc... Hmmmmm... But the curb is definitely not the back edge of sidewalk. In this case there was no described method to do it the easiest way. Nobody ever measured the bearings and distances from the Reference Marks to the Station. Duh. Reference Marks in broad daylight, shiny, happy 60 year old reference marks in the curb... I spent 50 minutes triangulating the station position to find it in the first place using all the esoteric methods that the former describers used. then once I found it I spent less than 5 minutes taking bearings and distances to the station from the reference marks. I included that in my recovery along with other repairs. Now it is a simple two tape find. The RM's are for finding the Station so Mike makes the best point, describe toward the station not away from it. On how many recoveries could we often repair this little mistake on alone?

 

Edit, Spelling.

 

Rob

Edited November 8, 2004 by evenfall