HomeMy WebLinkAboutWPO201800076 Correspondence 2018-10-16 (2)1
John Anderson
From:John Anderson
Sent:Tuesday, October 16, 2018 9:03 AM
To:'Daniel @ Line and Grade'
Cc:Frank Pohl; Ruth Emerick; Ryan Cheney
Subject:RE: FW: Misty Mountain Camp - 2016 LiDAR data
Daniel,
I realize the disruption, and Engineering will be glad to perform an initial review of the drainage repair design
in parallel with a field survey. Please include Note on plans stating ‘The Engineer has visually verified grades
in the field, and believes grades generally conform with the data.’ I believe we can keep things on track. Then,
as you propose, when survey data is available, design will be updated as/if needed (email sent 10/15/2018 5:38
PM). It’s a sound approach –a flexible response. Thanks for email, below. We appreciate the detailed
perspective, updates on LiDAR’s apparent usefulness in this instance. Whether state code or county ordinance,
my mistake highlights risk of advising without confirming what is permissible. Staff-level reviews avoid
crossing boundaries; it is a disservice to applicants and county, alike. We try to approve to the very limit of
acceptable design, while recognizing limits. At times, positions that appear reasonable are
impermissible. Please let me know when applications are submitted. I will try to complete initial review within
two days, but since off Friday, it will likely be Monday before you receive comment on Misty Mountain Camp
VESCP and FDP Applications. Thanks Daniel
-best,
J. Anderson 434.296-5832 –x3069
From: Daniel @ Line and Grade <dhyer@line-grade.com>
Sent: Monday, October 15, 2018 9:01 PM
To: John Anderson <janderson2@albemarle.org>
Cc: Frank Pohl <fpohl@albemarle.org>; Ruth Emerick <remerick@albemarle.org>; Ryan Cheney <rcheney@line-
grade.com>
Subject: Re: FW: Misty Mountain Camp - 2016 LiDAR data
John,
I've now been able to go through this in a bit more detail. I confess I have not read all of these documents in
their entirety. I find myself, once again, leaning to read between the lines... which didn't go over very well for
me with the Foglia Residence project. ;) And, I feel that I cannot make a case strong enough to over rule the
state code you provided. Nonetheless I have a few observations:
1) The data sets listed on the county's website (DEM, DTM, 4' Contours and 2' Contours) does not include 2016
LiDAR. Interestingly enough, the surface we have on this Misty Mountain Project has allowed us to generate
contours at intervals of fractions of a foot. Which was necessary to really see the areas of ponding. I would
agree with the state code that using 2' or 4' contours for construction would be setting one's self up for failure.
However, there is an abundance of research (Here's some) that indicate that LiDAR is just as, if not more,
accurate than a field survey. (Also, image below)
2
1A) Just in case I was not clear: LiDAR is not Photogrammetry from drones. It is state provided data. VGIN
Geospatial Services. by the Virginia Information Technology Agency (VITA). I would imagine they had a
licensed professional surveyor help with this work....
2) Very recently (2018) we did a project for the County of Albemarle Facilities and Environmental Services
Division under our Term Contract. The scope of work included repairing a storm water basin that had been
neglected for decades. In the case of this project: County Staff provided us the LiDAR data to develop the repair
documents. The project is now complete and operational. Repair Documents for this project can be downloaded
here. If the County permits this on their own projects then it is worth considering the value of this data(!). This
is the same project that I sent you the report/study showing the accuracy of the LiDAR.
3) The Scope of Practice Memo you provided seems to indicate that Licensed Surveyors are permitted to
design surface storm water systems and incidental plans and profiles of roads. I'm not seeing the correlation
between that memo and what we are doing here. I do not know if I have mis-represented myself but I'm not a
land surveyor. Only a licensed Civil Engineer. If a Land Surveyor is permitted to design storwmater facilities
certainly a Civil Engineer can make the determination if a topographic surface is of a quality to feel confident in
the accuracy for the work he/she is performing. I'm actually a little shocked that a land surveyor is permitted to
design as much as this Memo allows:
Please let me know your thoughts on performing an initial review on the repair scheme in parallel with the field
survey.
As always, I welcome your feedback. But I felt like these points were worth making so we are all on the same
page about what is being presented.
Thank you,
3
--
Daniel Hyer, PE
Line + Grade
434-962-2430
On Mon, Oct 15, 2018 at 4:40 PM, John Anderson <janderson2@albemarle.org> wrote:
Daniel,
October 9, I misguided you badly by failing to recognize relevant sections of state code. As it stands, using GIS data
(contours/topo, LiDAR, etc.) for engineering purposes is not the same as having a survey done by a licensed surveyor,
and as I understand it, violates state code. Only surveys by a licensed surveyor can be used for design /
construction. Given this, please provide survey-based design of Misty Mountain Camp drainage improvements. The
county (website) provide specific cautionary disclaimer concerning non-survey datasets. I should have been aware that
LiDAR data is not acceptable, or at least cautious in stating it was. I will make every effort not to mislead in the
future. Despite stating 2016 LiDAR data may be used, I was wrong, regret the misstatement, and withdraw it. This was
a significant issue about a year ago (see attached documents).
Again, please note that on the elevation data on Albemarle County data download page, is warning that specific datasets
may not be used for design, modification, or construction of improvements to real property or for flood plain
determination. To continue on basis of poor advice carries a range of risk, including to your client, so it’s best at this
point to regroup, and arrange field survey for proposed drainage improvements at Misty Mountain. We regret the
inconvenience, and appreciate your help and understanding.
4
Please feel free to call if any questions. 434.296-5832 –x3069
Thank you
5
John Anderson, PE, Civil Engineer II ∙ (434) 296-5832 -x3069
Community Development Dept. │ Engineering Division
County of Albemarle │401 McIntire Road
Charlottesville, Virginia 22902-4596
From: John Anderson
Sent: Tuesday, October 9, 2018 2:59 PM
To: Daniel @ Line and Grade <dhyer@line-grade.com>
Cc: Ryan Cheney <rcheney@line-grade.com>; Neale Craft <ncraft@albemarle.org>; Ruth Emerick
<remerick@albemarle.org>; Frank Pohl <fpohl@albemarle.org>
Subject: RE: Misty Mountain Camp
Daniel, thanks for the report –hope to read it, soon. Please use 2016 LiDAR for design work at Misty Mountain
Camp. Please feel free to call if any questions. Thanks again, best, J. Anderson 434.296-5832 –x3069
From: Daniel @ Line and Grade <dhyer@line-grade.com>
Sent: Tuesday, October 09, 2018 2:54 PM
To: John Anderson <janderson2@albemarle.org>
Cc: Ryan Cheney <rcheney@line-grade.com>; Neale Craft <ncraft@albemarle.org>; Ruth Emerick
<remerick@albemarle.org>; Frank Pohl <fpohl@albemarle.org>
Subject: Re: Misty Mountain Camp
We've found 2016 LiDAR to be hyper-accurate. In many cases too accurate as it gives more definition to the
surface than is needed. In the case of Misty Mountain Campground the terrain is so flat that we are seeing
much more detail in the LiDAR than the GIS. So, it would be my preference to use it.
Of course we'll still show the other resources via GIS.
In case you are interested, the attached report shows some of the detail we can see with a LiDAR surface.
thanks,
6
--
Daniel Hyer
Line + Grade
434-962-2430
On Tue, Oct 9, 2018 at 2:48 PM, John Anderson <janderson2@albemarle.org> wrote:
Daniel,
Is the goal a level of detail not possible with County GIS data? I have a sense –but can’t quote ordinance –that
development applications typically rely on (may require) county GIS topographic information, with recent field survey
data required for SWM design. Recalling our discussion, I imagine the best outcome for Misty Mountain Camp
drainage issues /design /ESC measures requires using the most accurate survey data available –is that 2016 LiDAR data,
in your view?
· Ordinance may provide guide; I had hoped to check /search ordinance, but we’re having internal connection issues
with Code website.
· On-line publicly-available GIS data (http://www.albemarle.org/department.asp?department=gds&relpage=2908 )
lists this disclaimer:
7
Given County GIS disclaimer, Engineering favors equally accurate, or (current) more precise source of survey data as
basis of design. I’ve copied GIS /County Engineer, and invite their input. Thanks for your note.
-best
J. Anderson 434.296-5832 –x3069
From: Daniel @ Line and Grade <dhyer@line-grade.com>
Sent: Tuesday, October 09, 2018 2:19 PM
To: John Anderson <janderson2@albemarle.org>
Cc: Ryan Cheney <rcheney@line-grade.com>; Neale Craft <ncraft@albemarle.org>
Subject: Misty Mountain Camp
Hi John,
8
A few weeks ago we met to preliminarily discuss the grading plan for Misty Mountain Campground.
One point of clarification: we were intending to do this work based on 2016 LiDAR data which we have
found to be very accurate. Do you foresee this being problematic? Given the time frames and the nature of the
work I wouldn't suspect a full blown field survey is required. But we'd like to confirm that with you.
Thanks,
--
Daniel Hyer
Line + Grade
434-962-2430
1
John Anderson
From:John Anderson
Sent:Thursday, October 11, 2018 1:10 PM
To:Frank Pohl
Subject:RE: Misty Mountain Camp
Perfect, thanks Frank
From: Frank Pohl
Sent: Thursday, October 11, 2018 12:10 PM
To: John Anderson <janderson2@albemarle.org>
Subject: RE: Misty Mountain Camp
John,
This section also applies:
Frank V. Pohl, PE, CFM
County Engineer
401 McIntire Road
Charlottesville, VA 22902
434-296-5832 (ext. 7914)
From: John Anderson
Sent: Thursday, October 11, 2018 8:54 AM
To: Daniel @ Line and Grade <dhyer@line-grade.com>
Cc: Ryan Cheney <rcheney@line-grade.com>; Frank Pohl <fpohl@albemarle.org>
Subject: RE: Misty Mountain Camp
Daniel, regret delay responding.
1. Floodplain: Activity is permissible by right as accessory to recreational use, ref. 18-30.3.11, Table /Permitted and
Prohibited Uses and Structures. A longer path to approval: water conveyance is permissible with a special use
permit. There is no regulatory floodway (VFRIS image). Engineering views project as a by-right use accessory
2
to a permitted recreational use. We do, however, need a FDP Application –please take time with this Application
(link, below), and include ‘No Rise’ Certification (example, attached).
2. WPO Encroachment: No need to mitigate buffer impacts since drainage improvements to remediate ponding are
so limited they may be viewed as a miscellaneous use (if not for ponding, there’s no project). This is not a
development project, per se. Note: Mitigation for stream buffer impacts is assigned automatically only to stream
crossings for roads, streets, or driveways (17-604.C.5.). Engineering may seek or request mitigation of other
development impacts to stream buffers, which are considered on case-by-case basis. In this instance, we
anticipate limited encroachment (single storm line?). We appreciate these question, and affirm Ch. 17, Article 6
places a number of restrictions on uses or activities that may occur in a stream buffer. 18-30.3 is likewise very
restrictive for activities, use, or structures proposed in the flood hazard overlay district (FEMA mapped
floodplain).
We hope this helps, thanks Daniel
VFRIS, Link: http://cmap2.vims.edu/VaFloodRisk/vfris2.html
18-30.3.11 /Table
3
Link, FDP Application:
http://www.albemarle.org/upload/images/forms_center/departments/Community_Development/forms/Engineering_an
d_WPO_Forms/Floodplain_Development_Permit.pdf
4
From: Daniel @ Line and Grade <dhyer@line-grade.com>
Sent: Tuesday, October 09, 2018 5:38 PM
To: John Anderson <janderson2@albemarle.org>
Cc: Ryan Cheney <rcheney@line-grade.com>; Frank Pohl <fpohl@albemarle.org>
Subject: Re: Misty Mountain Camp
Hello John,
Another question for you. As you can see in the image below, the Flood Plain (WPO Buffer) -- we may
encroach into this area to daylight the new ditch.
We're hoping, given the nature of this maintenance/repair work to confirm 2 things:
1) This work will not be considered a flood plain impact. There will be no fill in the flood plain (some cut). My
memory of our conversation recalls that we will submit an Flood Plain Development Permit but will check "No
anticipated Impact"
2) As such, do we anticipate needing to mitigate this encroachment into the WPO?
thanks in advance.
5
--
Daniel Hyer
Line + Grade
434-962-2430
On Tue, Oct 9, 2018 at 2:59 PM, John Anderson <janderson2@albemarle.org> wrote:
Daniel, thanks for the report –hope to read it, soon. Please use 2016 LiDAR for design work at Misty Mountain
Camp. Please feel free to call if any questions. Thanks again, best, J. Anderson 434.296-5832 –x3069
6
From: Daniel @ Line and Grade <dhyer@line-grade.com>
Sent: Tuesday, October 09, 2018 2:54 PM
To: John Anderson <janderson2@albemarle.org>
Cc: Ryan Cheney <rcheney@line-grade.com>; Neale Craft <ncraft@albemarle.org>; Ruth Emerick
<remerick@albemarle.org>; Frank Pohl <fpohl@albemarle.org>
Subject: Re: Misty Mountain Camp
We've found 2016 LiDAR to be hyper-accurate. In many cases too accurate as it gives more definition to the
surface than is needed. In the case of Misty Mountain Campground the terrain is so flat that we are seeing
much more detail in the LiDAR than the GIS. So, it would be my preference to use it.
Of course we'll still show the other resources via GIS.
In case you are interested, the attached report shows some of the detail we can see with a LiDAR surface.
thanks,
--
Daniel Hyer
Line + Grade
434-962-2430
On Tue, Oct 9, 2018 at 2:48 PM, John Anderson <janderson2@albemarle.org> wrote:
Daniel,
Is the goal a level of detail not possible with County GIS data? I have a sense –but can’t quote ordinance –that
development applications typically rely on (may require) county GIS topographic information, with recent field survey
data required for SWM design. Recalling our discussion, I imagine the best outcome for Misty Mountain Camp
drainage issues /design /ESC measures requires using the most accurate survey data available –is that 2016 LiDAR data,
in your view?
· Ordinance may provide guide; I had hoped to check /search ordinance, but we’re having internal connection issues
with Code website.
· On-line publicly-available GIS data (http://www.albemarle.org/department.asp?department=gds&relpage=2908 )
lists this disclaimer:
7
Given County GIS disclaimer, Engineering favors equally accurate, or (current) more precise source of survey data as
basis of design. I’ve copied GIS /County Engineer, and invite their input. Thanks for your note.
-best
J. Anderson 434.296-5832 –x3069
From: Daniel @ Line and Grade <dhyer@line-grade.com>
Sent: Tuesday, October 09, 2018 2:19 PM
To: John Anderson <janderson2@albemarle.org>
Cc: Ryan Cheney <rcheney@line-grade.com>; Neale Craft <ncraft@albemarle.org>
Subject: Misty Mountain Camp
Hi John,
8
A few weeks ago we met to preliminarily discuss the grading plan for Misty Mountain Campground.
One point of clarification: we were intending to do this work based on 2016 LiDAR data which we have
found to be very accurate. Do you foresee this being problematic? Given the time frames and the nature of the
work I wouldn't suspect a full blown field survey is required. But we'd like to confirm that with you.
Thanks,
--
Daniel Hyer
Line + Grade
434-962-2430