Map Review

[David Kendall]

As a seasoned map checker, I would ask for radial bearings on all points of reverse curvature (PRC), point of compound curvature (PCC) and any non-tangent curves. Additionally, I would ask that the radial bearing, both direction and annotation, be directed towards the radius point on a PCC.

The basis for the request is to be able to determine the direction of curvature. On flat PCC or PRC curves or short curves without a detail the map scales does not distinguish the direction of concavity. Having the radial bearings shown on the map saves a ton of time for the next surveyor. The alternative is to request a detail. Labeling a bearing takes minutes, drafting details takes hours. Pick your poison.

DWoolley

I don't find radial bearings difficult to draw on a map but I probably wouldn't add them to tangent lines or curves. County Surveyor map review comment was "why do I not hold the given radius when retracing the curves?" I was holding monuments and line tangency instead as it makes the map cleaner and I truly believe that the first time a curve (or line) is drawn on the map is the last time it will be perfect on the ground in any of the given elements anyway so what difference does it make? Any curve with a radius over 30 or 40 feet is impossible to tell if the radius is off a tenth or two.

Back in Texas the custom was to list chord bearing and chord distance for curve data along with your radius and delta. These two profound items can serve as one of the three elements defining a curve on a map. This solution solves all of the problems you guys are describing here with your radial bearings and detail drawings. It also dramatically simplifies the issue for the poor schmuck who has the misfortune to layout your goofy compound curve on the ground.

Everytime I suggest the chord bearing and distance to a CA surveyor they look at me like I got a booger on my chin so I stopped trying. To me it's just like the centerline monument in the middle of the freeway idea....

Leave it to a Californian to make an issue gratuitously complex then try to propose a solution to make it look easy! Sometimes I just sit back and wonder....Seasoned map-checker? Please, tell me more about this! Explain the practical value of the arc length on the curve data....

Someday, when I get to be a seasoned map-checker, I am going to request chord bearings on every survey plat and on subdivisions I'll require deflection angles and tangent lengths because I feel this is how it ought to be. More curve data on maps is protecting the public from unfortunate curve construction

[DWoolley]

To be clear, there is no need to show a radial bearing at the beginning of curve (BC) or the end of curve (EC) of a tangent curve. Wattles states the presumption is the curve is tangent unless stated otherwise. My example, requiring a radial bearing, was for PCC and PRC - at the point of reversal or compound. An added benefit is the radial bearing provides a check on the delta.

DWoolley

[PLS7393]

I'm so happy everyone feels my simple poll is a good place to ask mapping questions. What other topics would you like me to begin a post for? LOL!!!

As a seasoned map checker, . . . Additionally, I would ask that the radial bearing, both direction and annotation, be directed towards the radius point on a PCC.
DWoolley

Dave, what reference do you have that shows a radial line is towards the radius point?

My reference states the same as L. Stevens states, "RADIAL or RADIAL BEARING: A radial line is any straight line extending from the center of a defined circle to the circle's circumference. A radial bearing is the direction of a given radial line. On plats the work radial next to a bearing indicates that the line is radial from the center of the given circle"
(See Boundary Control and Legal Principles, by Brown, second edition.)

[William Magee]

As a seasoned map checker, I would ask for ........

DWoolley

I know a lot of seasoned map checkers.

Some have 30 years of experience.

Some have 1 year of experience, 30 times.

The latter seem more adament that their way is the “right” way.

[Jim Frame]

Dave, what reference do you have that shows a radial line is towards the radius point?

I think he meant that the bearing label should be placed on the map between the radius point and the curve as a way of visually indicating the location of the radius point. We probably all agree that the bearing quadrant should always be chosen to indicate the bearing *from* the RP *to* the curve.

[mpallamary]

When preparing a map, it is good practice to include enough data, especially with regards to curves, to annotate the in such a way that they are conducive to future use and modification. The map may serve as the basis for an easement description or some other segregation. When describing a curve, how does one describe the curve points? "A radial to said point bears XXXXXXX" perhaps? It is preferable to prepare any map or description in such a way that it avoids reverse calls. Food for thought.

[Gwen del Castillo]

Illinois Plat.pdf

I also lurk on another Surveyor chat room. Apparently in Illinois, they don't need no stinking radials!

[David Kendall]

Apparently in Illinois, they don't need no stinking radials!

I believe the radial bearing at the midpoint of the arc is coincident with the line perpendicular to the midpoint of the chord. That's a good one!

They should probably provide a detail.... Damn Yankees!

[btaylor]

This plat needs several radial lines. I don't think the curves for that access easement strike the lot line at a tangent either.

[Scott]

PLS7393, Sorry about the hi-jack, but back to the OP subject:
Certificate of Corrections submitted Jan. 8, 2019 and still no word about them. Almost twice as long as allowed by:
Government Code - GOV
TITLE 7. PLANNING AND LAND USE [65000 - 66499.58]
DIVISION 2. SUBDIVISIONS [66410 - 66499.38]
CHAPTER 3. Procedure [66451 - 66472.1]
ARTICLE 7. Correction and Amendment of Maps [66469 - 66472.1]
66471.(b) As to a certificate of correction, the county surveyor, city surveyor, or city engineer shall have 20 working days in which to examine the certificate of correction for compliance with Sections 66469 and 66470, endorse a statement on it of his or her examination and certification, and present it to the county recorder for recordation. In the event the submitted certificate of correction fails to comply with Sections 66469 and 66470, the county surveyor, city surveyor, or city engineer shall return it within the same 20 working days to the person who presented it, together with a written statement of the changes necessary to make it conform to the requirements of Sections 66469 and 66470.

I did not find any mention of what is supposed to happen if they do not make the 20 working day limit, so the above is probably toothless.

[PLS7393]

Over 1100 views and only 18 votes? I'm guessing the three (3) "Acceptable" votes are in government, or map checkers.

As Phil says, Surveyor to Recorder may be a valid point!

[dedkad]

Radial – the bearing of a radial line is the bearing
from the radius to a point on the curve.

I'm hoping that's what Mr. Woolley meant, otherwise it would be confusing to future surveyors.

[Scott]

My Certificate of Corrections finally were recorded March 12, 2019.

Jurisdictional Surveyor signed them February 13, 2019.

I submitted two COCs for different recorded maps.

3 COCs were recorded, all 3 were copies of just 1 of the 2 that I submitted.

You gotta laugh, it will all get worked out, I'm sure...

[bruce hall]

The radial "radiates" from the radius, isn't that correct?

[Scott]

Yes, from the radius point out.

Like a "ray" of light from the sun always travels in the direction away from the sun.

[William Magee]

The radial "radiates" from the radius, isn't that correct?

I suppose.

Unless, of course, you are standing at the POT and want to lay out the curve from there.

[bruce hall]

it is or it isn't. one of the two. shouldn't be either/or.

what do I know?

[Lee Hixson]

As I'm constructing a legal description my surveyor brain places me, vicariously, at the BC and, as I get into the specifics of the curve data I look from that point toward the radius point. Makes intuitive sense. No reason to insist on one or the other...they both work.

[Peter Ehlert]

As I'm constructing a legal description my surveyor brain places me, vicariously, at the BC and, as I get into the specifics of the curve data I look from that point toward the radius point. Makes intuitive sense. No reason to insist on one or the other...they both work.

I agree.

It is Our job to make it super clear what we intend when we write descriptions... especially when we refer to a radial bearing.
The problem is, some people are locked into some "definition" of how it "must be" because of a preconceived notion...
*it is clear Radial Bearing can have more than on meaning (see comments above)

In my pea brain using a phrase like "from which the radius point bears (bearing)" is unambiguous.

[mpallamary]

When Paul Cuomo, Roy Minnick and I wrote Advanced Land Descriptions, one of our goals was to try and eliminate ambiguities such as this.

A radial originates from the center of the curve, also known as the Radius Point - the Radius Point is where all things originate from.

It is the source of the rays. The name comes from the Latin radius, meaning ray but also the spoke of a chariot wheel

https://en.wikipedia.org/wiki/Radius

[dedkad]

Leave it to a Californian to make an issue gratuitously complex then try to propose a solution to make it look easy! Sometimes I just sit back and wonder....Seasoned map-checker? Please, tell me more about this! Explain the practical value of the arc length on the curve data....

The arc length is helpful to use for reviewing stationing on a set of construction plans. Providing offsets from a chord isn't so helpful when you're trying to figure out the alignment of a sewer line in the street in relation to the centerline.