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Tangent Curve? What's That?

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Luke CO PLS
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Had to check a Legal Description for a developer before they executed the deed.
It was for a ditch relocation which was going to separate the open space from the Phase 4 development.
The Tech that created it did a good job. It mathematically closed.
But I had to wonder about the geometry of it all with 86 courses and having 34 curves of which none were tangent! NONE!
Asking myself if that Tech worked for me, would I have made them do it over?
Would I mentor that person in how to set up the centerline alignment and have every curve be tangent and then just offset to each side?
Being old-school I think I would have done that (perhaps even before they finished the job)!

Glad to be retired so I only have to see this once in a while.


 
Posted : November 15, 2017 8:03 am
a-harris
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To do it justice, you would need to fix the entire route from end to end and thus, making some monuments being in the wrong place.
When monuments rule over math, you get non tangent curves.


 
Posted : November 15, 2017 8:17 am
peter-ehlert
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Luke does the legal provide adequate data to calc the true curve data? Like radial bearings or some such.
I have prepared many maps and descriptions that had non-tangent curves, lots of them. But those were Found to be non-tangent from a combination of hard evidence. Existing Situation.
There is no excuse for creating a new alignment like that. You should see if you can confer with the Tech directly and explain how things work.
... did some "engineer" or "surveyor" review and bless this crude product? Hunt that person down and do some face slapping, in private.


 
Posted : November 15, 2017 8:31 am
Jim in AZ
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A Harris, post: 455652, member: 81 wrote: To do it justice, you would need to fix the entire route from end to end and thus, making some monuments being in the wrong place.
When monuments rule over math, you get non tangent curves.

What monuments?


 
Posted : November 15, 2017 8:32 am
a-harris
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Something has to be in place to retrace the boundaries and easements.


 
Posted : November 15, 2017 8:34 am

peter-ehlert
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A Harris, post: 455662, member: 81 wrote: Something has to be in place to retrace the boundaries and easements.

how about CORS ties? it is getting common
with proper metadata it can work well


 
Posted : November 15, 2017 8:55 am
Kris Morgan
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Luke CO PLS, post: 455650, member: 1220 wrote: Had to check a Legal Description for a developer before they executed the deed.
It was for a ditch relocation which was going to separate the open space from the Phase 4 development.
The Tech that created it did a good job. It mathematically closed.
But I had to wonder about the geometry of it all with 86 courses and having 34 curves of which none were tangent! NONE!
Asking myself if that Tech worked for me, would I have made them do it over?
Would I mentor that person in how to set up the centerline alignment and have every curve be tangent and then just offset to each side?
Being old-school I think I would have done that (perhaps even before they finished the job)!

Glad to be retired so I only have to see this once in a while.

Why do they have to be tangent? If you're tying to fit a feature it may not be tangent, say such as a drainage ditch. I'm a HUGE fan of three point curves which fit was is there but may not be tangent. I've yet to chase a highway curve that was truly laid out and monumented as tangent. I've seen some that are close but mostly not. The only thing where I really work on tangency is on railroads because of the way the rails are spiral, curve, spiral, you can't really work with the centerline, as it exists today, to come up with the simple curves of the 19th century. But you can use the tangents, PI's and tangent distances to generate tangent curves that work VERY well. Otherwise, who cares if the curve is tangent or not?


 
Posted : November 15, 2017 9:23 am
lmbrls
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If an alignment is being created, there is no excuse for the curves not to be tangent. If you are defining an existing alignment like an old roadway or other feature that just happened and was not designed, you have the option of
1. Using a tangent curve that doesn't quite fit the existing alignment.
2. Creating a PI no curve before and/or after the curve to make it tangent.
3. Using a non tangent curve that fits the existing alignment.
4. Define the alignment by short chords.

The approach for the specific applications "depends". Sometimes a tangent curve does not fit the situation.


 
Posted : November 15, 2017 9:36 am
aliquot
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If the engineers are OK with non tangent curves why should the surveyor care? As long as enough curves elements are given a non tangent curve is just as easy to locate as a tangent curve.


 
Posted : November 15, 2017 9:45 am
daniel-ralph
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I don't know how much from tangent the description is but let me guess; the preamble of the description cites something like the centerline of a ditch which is the following courses and distances...
Oh sure the ditch was located/measured in significant detail to warrant the non-tangent description. Its a ditch! And besides, that's what my fancy program said to do.
I suggest that the OP recommend that the description be rejected and that another be crafted that will not cause distress to the adjacent development and those who have to regenerate its location. And thank them for allowing you to review it.
As to "if the engineers are OK with"... I reject that premise. I don't know but a very small handful of engineers that are qualified to speak on the subject of legal descriptions much less craft one.


 
Posted : November 15, 2017 1:31 pm

brad-ott
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Why would an "engineer" make this curve non-tangent?
Why?

EDIT: it only took this "surveyor" several hours to discover that it was non-tangent (it seems so obvious now, doesn't it?).


 
Posted : November 15, 2017 3:02 pm
scott-ellis
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What kind of Utility Easement is a DUE? I have never seen a DUE before.


 
Posted : November 15, 2017 3:41 pm
Kris Morgan
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Scott Ellis, post: 455771, member: 7154 wrote: What kind of Utility Easement is a DUE? I have never seen a DUE before.

Dedicated Utility Easement????


 
Posted : November 15, 2017 3:43 pm
stacy-carroll
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Drainage & Utility


Me. "What's the difference?"
T.C. Carroll "It's the difference between right and wrong!"

 
Posted : November 15, 2017 3:44 pm
scott-ellis
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Stacy Carroll, post: 455774, member: 150 wrote: Drainage & Utility

That makes sense in my area it is common to have it as D.E. & U.E.


 
Posted : November 15, 2017 3:45 pm

jkinak
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I see that you are in CO.
CRS 12-25-202. Definitions
[INDENT](6) (a) "Professional land surveying" means the application of special knowledge of principles of mathematics, methods of measurement, and law for the determination and preservation of land boundaries.[/INDENT]

Clearly legal descriptions are for the determination and preservation of land boundaries. So do you need special knowledge of mathematics and law to prepare a valid, defensible legal description? Given the large volume of discussions on this forum, disagreements in the interpretation of legal descriptions and court cases related to legal descriptions - the answer is a solid YES.

Luke CO PLS, post: 455650, member: 1220 wrote: The Tech that created it did a good job. It mathematically closed.

Not knowing the CO statutes very well I ask - are unregistered technicians exempt from the law?

If not, just ask the PS in responsible charge over the tech why they did it.
AND
If there is not PS in responsible charge then it looks to me like you are obligated to report it.
12-25-208. Disciplinary actions - grounds for discipline
[INDENT](1) The board has the power to deny, suspend, revoke, or refuse to renew the license of, or place on probation, limit the scope of practice of, or require additional training of any professional land surveyor or land surveyor-intern for:
(h) Failing to report to the board any professional land surveyor known to have violated any provision of this part 2 or any board order or rule;[/INDENT]

I realize that we all "just want to get along" - me too (and we don't want to alienate clients) but I suspect that you need to explain to your client that the law requires that legal descriptions be prepared by a PS licensed in CO (and they may need to be stamped (see 12-25-217(2) below). They need to know that the law does this to help avoid all of the downstream problems that a improperly prepared "forever" document like a legal description can create. The client also needs to know that if you don't report it, you may be jeopardizing your livelihood (although it's my understanding that non-reporting is rarely prosecuted).

As much as we all loath to do so - If preparing a legal description falls under the definition of Professional land surveying - then it's appropriate to educate your client about the law - let them know that you can write the legal description or that you can give them the names of others qualified to do so, but you can't use it. If you want to make it your product - then feel free to do so if it's OK with the client if you use their tech's work (which it sounds like they have already agreed to do. ).

AND
It sure looks like it needs to be sealed because it's a document resulting from the practice of land surveying (see definition 12-25-202 (6)(a)) UNLESS there's a statutory exemption for legal descriptions (which there may be - I don't really know CO law)
12-25-217. Professional land surveyor's seal ƒ?? rules.
[INDENT](2) All documents, plats, and reports resulting from the practice of land surveying shall be identified with and bear the seal or exact copy thereof, signature, and date of signature of the land surveyor in responsible charge.
(3) A professional land surveyor shall use a seal and signature only when the work to which the seal is applied was prepared under the professional land surveyor's responsible charge.[/INDENT]

It's always been common practice around here to NOT stamp legal descriptions that are parts of deeds/easements etc. After reading the law (in AK), it's clear that they are REQUIRED to be sealed and signed. If we all did that then the clients would begin expect it and EVENTUALLY, we'd see fewer legal descriptions written by unqualified people.


 
Posted : November 15, 2017 5:40 pm
FrozenNorth
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JKinAK, post: 455800, member: 7219 wrote: I see that you are in CO.
CRS 12-25-202. Definitions
[INDENT](6) (a) "Professional land surveying" means the application of special knowledge of principles of mathematics, methods of measurement, and law for the determination and preservation of land boundaries.[/INDENT]

Clearly legal descriptions are for the determination and preservation of land boundaries. So do you need special knowledge of mathematics and law to prepare a valid, defensible legal description? Given the large volume of discussions on this forum, disagreements in the interpretation of legal descriptions and court cases related to legal descriptions - the answer is a solid YES.

Not knowing the CO statutes very well I ask - are unregistered technicians exempt from the law?

If not, just ask the PS in responsible charge over the tech why they did it.
AND
If there is not PS in responsible charge then it looks to me like you are obligated to report it.
12-25-208. Disciplinary actions - grounds for discipline
[INDENT](1) The board has the power to deny, suspend, revoke, or refuse to renew the license of, or place on probation, limit the scope of practice of, or require additional training of any professional land surveyor or land surveyor-intern for:
(h) Failing to report to the board any professional land surveyor known to have violated any provision of this part 2 or any board order or rule;[/INDENT]

I realize that we all "just want to get along" - me too (and we don't want to alienate clients) but I suspect that you need to explain to your client that the law requires that legal descriptions be prepared by a PS licensed in CO (and they may need to be stamped (see 12-25-217(2) below). They need to know that the law does this to help avoid all of the downstream problems that a improperly prepared "forever" document like a legal description can create. The client also needs to know that if you don't report it, you may be jeopardizing your livelihood (although it's my understanding that non-reporting is rarely prosecuted).

As much as we all loath to do so - If preparing a legal description falls under the definition of Professional land surveying - then it's appropriate to educate your client about the law - let them know that you can write the legal description or that you can give them the names of others qualified to do so, but you can't use it. If you want to make it your product - then feel free to do so if it's OK with the client if you use their tech's work (which it sounds like they have already agreed to do. ).

AND
It sure looks like it needs to be sealed because it's a document resulting from the practice of land surveying (see definition 12-25-202 (6)(a)) UNLESS there's a statutory exemption for legal descriptions (which there may be - I don't really know CO law)
12-25-217. Professional land surveyor's seal ƒ?? rules.
[INDENT](2) All documents, plats, and reports resulting from the practice of land surveying shall be identified with and bear the seal or exact copy thereof, signature, and date of signature of the land surveyor in responsible charge.
(3) A professional land surveyor shall use a seal and signature only when the work to which the seal is applied was prepared under the professional land surveyor's responsible charge.[/INDENT]

It's always been common practice around here to NOT stamp legal descriptions that are parts of deeds/easements etc. After reading the law (in AK), it's clear that they are REQUIRED to be sealed and signed. If we all did that then the clients would begin expect it and EVENTUALLY, we'd see fewer legal descriptions written by unqualified people.

Do you think this was the intent of the law or is this simply a letter-of-the-law interpretation? I actually think it sounds like a great practice. Have you advised DOT (one of the largest producers of legal descriptions in the state) that they are consistently in violation of the law?


 
Posted : November 15, 2017 5:56 pm
jkinak
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FrozenNorth, post: 455801, member: 10219 wrote: Do you think this was the intent of the law or is this simply a letter-of-the-law interpretation? I actually think it sounds like a great practice. Have you advised DOT (one of the largest producers of legal descriptions in the state) that they are consistently in violation of the law?

I do think this is both the intent and letter of the law. I suspect that the folks who are NOT stamping legal descriptions (in AK) are simply unaware of the law. I have shared information regarding seals and the statutes at ASPLS meetings in Anchorage. There was a fair amount of "we've never done that" and "DOT and the MOA don't require it" and "attorney's do them all the time" and so forth but there was no disputing what the law said, nor was there any doubt that it would benefit downstream users. I don't know the law well enough to know if attorneys can legally write legal descriptions but I do know what the statute says about surveyors. I also know that if the expectation is to see a seal, some (possibly many/most) people will start demanding it.

DOT (in AK) is a state entity so they aren't required to have a corporate authorization - it's the registrants responsibility (whether working for DOT or a borough or whoever) to seal all final products in AK.
Sec. 08.48.221. Seals. (a) ...When a registrant issues final drawings, specifications, surveys, plats, plates, reports, or similar documents, the registrant shall stamp the documents with the seal and sign the seal....

So it's the registrants responsibility to seal final surveys, plats, documents regardless of DOT's (or any other client/employer) position on the matter.
This would also apply to parcel plats/parcel exhibits.
I'm not aware of DOT rejecting any legal descriptions because they were sealed and signed.


 
Posted : November 15, 2017 6:20 pm
Luke CO PLS
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OK. Back to address some of the issues mentioned today:
1. This was a new ditch. No monuments.
2. The Legal Description had adequate data to calc the location.
3. There was nothing to match into. Just a ditch. All the cuts and fills fall within the 40ƒ?? width.
4. The description went down one side and back up the other side. The sides were not congruent in any way.
5. This Legal Description was signed and sealed by a PLS. It closed. I could follow it and calculate it. No problem with any of that.
Just why not use tangent curves when you can?
To me it is a sign of an untrained survey tech or engineering tech.
Kind of like a button pusherƒ??ƒ??
We can do better.


 
Posted : November 15, 2017 10:39 pm
charles-l-dowdell
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A lot of municipalities have incorporated in their subdivision regulations & design standards the all curves be designed as tangent curves.


 
Posted : November 15, 2017 11:28 pm

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