Closure Reports and sanity…………

[Ian Wilson]

I just got the first set of requested revisions back from a certain city for a simple Parcel Merger. Two rectangular lots being consolidated into one. Same individual owns both.

The closure around the merged parcel was “perfectâ€￾ (1:INFINITY). It is a rectangular lot – opposite sides parallel. That’s not good enough. The closure has to be expressed in…


wait for it…


THOUSANDS OF AN INCH!!!

I’m hoping this is an error on the part of the reviewer…We’ll see tomorrow.

[Gromatici]

Infinity is 0.00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000...............................
and that’s impossible unless you are carrying out your seconds to infinity and that is impossible unless you are surveying with an electro microscope. Significant figures really should only require that we close within 0.01' and reporting our results in the appropriate decimal places too.
I normally supply closures out at least to the thousandth because the software is set up to do so. Carlson, LD and others are set up that way. I've worked at several firms and they all do it this way, and we check maps and expect the same.

[Ian Wilson]

Eric! Y'all work in inches? You KNOW what they say about peole wh owork in inches!

[Jim Frame]

When a 4-sided parcel is a parallelogram I don't provide closure calculations, I simply state that the parcel closes by inspection. So far I've not had to provide calculations, but I suppose someday I will.

[dmi]

I feel your pain. Aren't you glad you do not have a couple of curves in there!!!!

I work with a closure program one time where you could change .005' to .004'
and then all the hundreths would add up. Natually we printed out the closure report to 0.00'.
Why do we do closure reports for map submittals? It certainly not to prove that the parcel closes perfectly. What we are aiming at is providing evidence
that what has been drafted is labeled correctly.

We are trying to prove the drafting so it does not matter if there are small rounding errors, or if the closure is 1:10,000 or !:1,000,000. these days in most cases it is easy to have closures with really small errors. It looks like it is time for word processing magic. replace all "infinity" with 1,000,000 and call it a day.

I like what Jim said better and it has worked for my in the past.

[bruce hall]

"Listen fella, my boss gave me a checklist, and it says I need a printout showing a closure of less than 0.02', or your map don't fly. I know it's a square, I can see it's a square, but I don't see a printout, and I have to have one." I don't see a problem with that. I could say a whole bunch about inspection. I wouldn't need a narrative if all it took was inspection to review the map. (Well maybe that's being too tough)

[goodgps]

one in ten thousand boys. . . .

Check the standards. Just being less than 0.02' wont fly in court and with the board. 1:10,000 is the standard.

Sure we can close it better than that with fancy computors and all.

Whoever is checking this is violating his/her authority and looking pretty stupid. . . .plain and simple.

Go over this persons head to a licensed person. If this person is licensed, then an inquiry to the board is in order.
I really HATE to go this route but in a case like this it will be better for the industry.

It is not the goal of a land surveyor to "merely be licensed", but rather to continue the learning adventure throughout an entire carreer lifetime.

We dont reinvent the wheel, but we can smooth the rough edges off.

Grandpa "good"

[Gromatici]

Well, apparently I'm a doophus! Sorry Ian, I got got sidetracked by the "INFINITY" thing and totally missed your point. My bad. I'll wait by the wood shed for ya.

[Scott]

Ian, I saw that you stamp and seal your closures. Now that I think about it, it is a "report" generated by me and should be stamped, but I have not been doing that, nor can I think of seeing any stamped that come to me to check as a city surveyor. I will start stamping mine.
Question for everyone: Are you stamping your closures?

I did see the post about stamping cutsheets;
http://www.californiasurveyors.org/clsa ... +signature

My cut sheets are stamped and signed.

[PLS7393]

Planners, don't you love them???

But com on Ian, I know you can do better than that, heheheee. We are the superior profession, except planners make more and do less in most cities.

My past experience employed by a certain city allowed the survey section to do the survey related work for the city.

Bringing me to my next issue pertaining your situation. Who is reviewing, and overseeing the survey work, in responsible charge, for that particular city? Are planners doing survey related work, in reviewing descriptions for your Lot Merger?

Hmmmmm, interesting, very interesting. (rolls eyes).

As for your question Scott, I have only seen one or two closure reports with a seal and signature in 11 years of map review work, but I have seen them.

Now back to our regularly scheduled programming . . .

[Berk Blake, PLS CA]

Just add the inch " mark after infinity and I believe that you have satisfied the request. One wonders how they can allow you to work in decimals of feet with the inch closure req.

[Ian Wilson]

I had a nice chat with the “Junior Engineer” this morning.

He saw my point and agreed that the closure report was fine as is.

We discussed a number of points and clarified things.

I provided him with a copy of AG Op 94-809 to clarify my point regarding the dedicated lots on the original Parcel Map. I still maintain that the ownership is to the centerline of the streets and that any actions, LLO or merger or whatever, needs to address the lettered lots on the Parcel Map so that the changes apply to them as well. The dedication won’t change, but the disposition of the lettered lots may well change depending upon the action being requested.

All is right with the world once again….

As far as the stamp, really, anything going out of the office with an opinion or a professional action such as a calculation, description or the like, should bear your stamp and signature. If the work going out is a result of a professional action, stamp it!

[bruce hall]

"Check the standards. Just being less than 0.02' wont fly in court and with the board. 1:10,000 is the standard."

This is what I'm gonna do. I gonna tell Ray, Wanda, and Carlos, "Good says if I have a Lot that is 100 x50 then I got 0.03' closure. You take your 0.017' and do something with it."

Maybe in someone's dreams, but not mine. Not even in real life. I'll continue to send in my closures even if it is a rectangle, and I'll sure try and make them close by 0.017' or less. For no other reason than, "Just because it makes them happy". Although I'm gonna have a tough time stamping the closures. Maybe I should also stamp the copies of the recorded maps that I submit that I use as references. Granted I didn't perform the survey on these record maps, but I am stating that these maps are my references, and I am stamping them as such(I printed them up in my office and used them on my document that give a professional opinion.) I am being stupid here, folks, just trying to make some kind of a point, although I don't know what it is. Things used to be so much simpler.

[goodgps]

Of course we can produce wonderful multi-decimal place calculations to satisfy the public agencies need for mathmatecal proof. We have the easy "snap and poof" I will never advocate sloppiness I AM addressing the silliness of the request for Ian to produce this magical "perfect" closure report which is on a piece of paper (or electronic spread sheet).

Think of it this way. . . A generated closure report relates to the reality of the ground survey, as a restraining order relates to a violent perpetrator.
The closure report carries no warrantee that the actual ground survey is correct/ perfect.
and the "restrainee" can still getcha. just hold up the paper as he's stabbing you.

Now . . . if you stamp and sign the closure report, is that an implied warrantee that the ground survey truely matches the report ?

but then we do stamp our maps though '^)

And then we use a perfectly imperfect spheroid to define our coordinate system too.

[subman]

Darth,

For final maps and parcel maps in my County, our local ordinance specifies the 1:10,000 allowable closure error (copy below)

21.20.010 Standards for survey work.
A. The procedure and practice of all survey work done on any division of land, whether for preparation of a final map or parcel map, shall conform to the standards and details set forth in Chapter 15, Division 3, of the Business and Professions Code, the Land Surveyor’s Act. The allowable error of closure on any portion of a final map or parcel map shall be 1/10,000.
B. In the event that the county engineer, county road commissioner, the State Highway Engineer or any city engineer shall have established the centerline of any street or alley in or adjoining a division of land, the final map or parcel map shall show such centerline, together with reference to a field book or map showing such centerline and the monuments which determine its position. If determined by ties, that fact shall be stated upon the final map or parcel map. (Ord. 9071 § 11 (part), 1966: Ord. 4478 Art. 7 § 111, 1945.)

[Ben Lund]

What is the closure calculation being done on? Are you doing a closure calculation on
A. the field traverse
B. the AutoCAD lines representing the boundary solution
C. record bearings and distances
D. some conglomerate of the above
E. None of the above

[Gromatici]

Those reports can be faked. What if, in your surveying you find a 3" BC 100 years old along the r/w. The centerline monuments are all done by a subsequent survey 80 years later and you can only get the two to resolve within .02'. You and I both know that the old monument is really on the Right of Way, but the County or City won't accept it as being on the Right-of-Way because of the Law (which is in stark contrast to Case-law). Many Counties view the centerline as being superior, although in this case the old R/W is because it was set by the original subdivider and the centerline was done at a later time: City Eng. However, you look at your least-squares adjustment and see an error ellipse of 0.02'. You know that some other surveyor will have a 95% chance of measuring within 0.02' of that monument. That monument is on the right of way line. You’re not going to tell your client otherwise and decide that you'll just show it as 30' M&R. Now the trouble is: Parcel Closures. No problem! For most CAD users you’re just clicking on lines not points, so it's easy to create a Parcel Closure from lines that may or may not really represent the fieldwork done. It's that easy.

I've always thought it was really a check on the drafting of the final product and not really a check on the survey itself.

Should we report what we measure? Yes. Should we have to not accept something because our measurements are off by a "little"? NO!

[goodgps]

So we've explained the error of closure, the relationship of closures to surveys, old vs new monuments, centerline vs. sidelines, How inthe heck do we explain the moron who is requesting thousands of an inch for Ians closures ?

"good" ness gracious !

[Ian Wilson]

Good...

we don't...we just chalk it up to inexperience. I manag3ed to turn it into a learning experience. I don't think this will happen again in this jurisdiction...

Ian

[goodgps]

Greg, you are one of the "good" ones it sounds like guys like Ian is only one of a great many who you you're learning from.

Some guys obtain a map checking job and take it as a license to request any whim du jour [these guys must be from fresno state] HA HA

I had a map checker tell me my survey was wrond because I showed an angle point on the section line at the quarter corned AND the two "half" section lines werent equal. in otherwords he was tossing an old concrete monument set in 1918 which replaced the found original 4x4 rwd 1/4 corner.
I called him a moron too.

We are good friends now and he is studying for his LS.

Your'e not a moron, and I'm sure your kids love you. . . good job

Captian "Good"

[Ian Wilson]

I agree.

Closures no longer have anything to do with the field work. They are relative to the mapping alone.

With modern survey techniques, such as use of GPS equipment, and CAD programs for map drafting, the traditional Closure Report may well be a useless item, the sole purpose of which is to “pad” map check time. (The scenario in my original post likely cost my client an hour of time at approximately $150 per hour of review time on a deposit based fee.)

As an example, if the survey boundary is drafted as a closed 2D figure from found point to found point, and the internal portions are created by dividing the exterior boundary lines appropriately, what does the Closure Report provide? Other than a gross check for the reviewers, not much. The rounding error often displayed as a 0.01’ or 0.02’ discrepancy between the sum of the parts and the dimension shown for the whole is just that, a rounding error and not a survey or mapping error. The magnitude of that error will not likely create havoc in the field, the office of the court room. It certainly won’t create the same mess that the 9.33’ error I’m dealing with on a Record of Survey drafted in 1963 or the exactly 20.00’ error on a late ‘70’s Parcel Map that serves as the base map for a new Parcel Map about to record.

Hmmm….I have to shrug off huge multi-foot errors on record maps but I must resolve the computer’s 0.01’ rounding discrepancy on the sum of two line parts, each of which is over 800’ long.

[Jim Frame]

As far as I'm concerned, the sole purpose of closure calculations is to provide a check on the drafting. The use of CAD has reduced the frequency of blunders in map dimensions, but at the same time it has introduced new ways of creating those blunders. Without a closure report, the reviewer has no way to verify that the annotated dimensions are correct short of running the closures himself, and few of us want to see that happen.

[E_Page]

Perhaps I'm out of step with many, but I would consider not keeping notes, or raw DC files at least, to fall below the Standard of Care.

Storing coordinates only gives you no way to perform any error checking.

[Ian Wilson]

And what, pray tell, is wrong with “GPS surveyors”?

I perform most of my boundary surveys with GPS equipment. As I have shared many times, I use “pre-calculated” files “calibrated” to the job site to search for monuments and then use fast static observation techniques to collect the monument locations. I post-process the observation data files along with the observation files from local CGPS Stations to derive the positions of the found monuments.

Incidentally, the raw observation files are kept in a separate folder. The paper field notes, including point descriptions, pole heights, etc. are scanned and kept, along with the statistical files, in sub-folders.

And, no, I do NOT use RTK positions for my monument locations. They simply do not produce verifiable results and do not demonstrably produce solutions that are reliable 100% of the time. Knock on Roger or Alan’s door for a quick discussion about “RTK Boundary Surveys”.

I believe this is a methodology supported by both Messrs. Frank.

[Ian Wilson]

Greg:

Any decent GPS post-processing software should have the ability to define a network or closed figure once the data has been processed and adjusted. The definition of the network should include a statistical analysis of that figure which, for all intents and purposes, should suffice as the "closure" for the field portion of the work.

The mapping "closure" should be based on a closed 2D figure, the vertices of which coincide with the positional locations of the adjusted field points. In other words, the way we are forced to do things, the field closure is lost from our work and all that remains is the closure based on the ability of the software to calculate the bearings and distances between the adjusted points. The discrepancies will be based on rounding and the ability to generate point-to-point-to-point bearings and distances.

We are in a world where the traditional methodology has not yet caught up to the current technology.