SW4221001_Response To Comments_20230302

2537E. LYON STATION RD, STE 102
PO BOX 361
Ca�OESIFSN &
ENGINEERING, RLLC
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
February 22, 2023
CREEDMOOR, NC 27522
919 230-0996
Please find below responses to the comments for Fieldcrest Subdivision (0: 21-025)
provided on January 11, 2023 via email in bold green italics:
1. Please show the vegetated setback from the surface water on the plans. This item is
required per 15A NCAC 02H .1042(2)(g)(iii), .1003(4) & .1017(10).
The 30' buffer note has been added to sheet C-1.3 and C-1.4.
2. Please include a second low -density drainage area in Section IV, 10 of the
Application and on the Drainage Area Page of the Supplement-EZ Form. Typically,
low -density projects only have a single drainage area (the entire project area) but
since this project is located within two jurisdictions/drains to two differently
classified surface waters/subject to two different sets of rules, this project should
have two low -density drainage areas (see attached). The sum of the two low -density
drainage areas should add up to the entire project area.
The stormwater application section IV-10 has been revised.
3. Please exclude the on -site surface water area from the total/on-site drainage area
(project site area) in Section IV, 10 of the Application and the Drainage Areas Page
of the Supplement-EZ Form. NOTE: The density calculations appear to have already
excluded the on -site surface water area so these items should not need to be
changed.
The application and EZ form are now revised.
4. Please include the design information for the ditch perpendicular to the proposed
roadway, downstream of ditches 3, 5, & 6 (see attached).
Design information now included. This is not a ditch, but just weargrades were
pulled up to meet the invert of the pipe. We have ran the calcs however for the
runoff to ditched 3,5, and 6 through a trapezoidal channel as requested.
S. Please provide calculations showing that the culvert outlets are stable in accordance
with 15A NCAC 02H .1003(5).
The calculations are now provided.
6. Please provide documentation showing that 15A NCAC 02H .1017(9) (c) is being met
for this project.
The subdivision was designed to be low density to avoid the installation of SCM
according to NCDEQ Stormwater Design Manual E-1. The property density was
calculated to meet density thresholds according to 15A NCAC 2H.1003(2)(a)
and this should be also covered rules .1017, .1019, and .1021.

2537E. LYON STATION RD, STE 102
'3 DESIGN & PO BOX361
ENGINEERING, PLLC CREEDMOOR, NC27522
919 230-0996
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
7
Low density projects are not required to be equipped with Stormwater Control Measures
(CMs) in exchange for limiting their built -upon area, maximizing dispersed flow and
ensuring that stormwater conveyances are vegetated. These strategies protect the
hydrology of the receiving steam_ prevent erosion, and remove pollutants through infitkretion_
The general requirements for low density projects are covered in in Mule 15A NCAC 02H
.1003(2), and the specific built -upon area limit for low density are set forth in the stormwater
program to which they are subject_ For example, a project subject to NPOES MS4 and
Urbanizing Areas Rule 15A NCAC 02H _1017 would need to meet the requirements for
dispersed flow, vegetated conveyances, curb outlet systems, AND contain no more than
4% built -upon area or 2 dwelling unitslacre in order to be considered a low density project_
The built -upon area limits vary by stormwater prograrrr_
15A NCAC 2H .1003(2)(a): DENSITY THRESHOLDS. Low density projects shell not
exceed the law -density development thresholds set forth in the stormwater programs to
which they are subject pursuantto Mules _1-017, ,1019, and _1021 of this Section_ For
projects subject to the requirements for felon -Coastal High Quality Waters and Outstanding
Resource Waters, dwelling unit per acre may be used instead of density to establish low
density status for single-family detached residential development as set forth in Rule _1021 in
this Section.
Table t: Thresholds for Lowy Density Projects
tormwater Program
Maximum Percent BUA for Low Density
4 Stormwater
24%
Coastal County -- SA
12%
Coastal County - Freshwater ORW
12
Coastal County - Other
24°
Non -Coastal County - ORW and HQW
12
Water Supply Watershed
Varies based on W S classification;
see 15A NCAC 02H Rules_
Please correct the following issues with the Supplement-EZ Form:
o Cover:
■ Line 2 - Please exclude the on -site surface water area from this value
(This value should correspond to Section IV, 7 of the Application).
The EZ cover line #2 has been revised.
o Drainage Areas Page:
■ Line 5 & 6 - See earlier comment.
Line 5 and 6 are now revised.
Line 22 - This is noted, however, as noted in an earlier comment, this
project should have two low -density drainage areas.
The note has been revised.
LD Columns - Please enter the drainage area information for the two
low -density drainage areas.

2537E. LYON STATION RD, STE 102
DESIGN & PO BOX361
ENGINEERING, RLLC CREEDMOOR, NC27522
919 230-0996
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
The LD columns are now included.
o Low -Density Page:
■ Line 11- This item is not applicable if curb outlet swales are being
use and should only be "Yes" if the curb outlet swales are being
designed in accordance with 15A NCAC 02H .1061 (These ditches do
not appear to be designed to these design standards).
This has been revised to say no.
Swales 2, 3, & 7 - There appears to be a slight rounding error in the
drainage area values for these ditches. For example, the calculations
show the drainage area of ditch 2 as 0.28 ac while this form shows
0.29 ac. Please revise as needed.
These sections now match.
Please provide the following:
8. 1x hard copy & 1x electronic copy of the revised pages of the Application Form.
Understood
9. 1x hard copy & 1x electronic copy of the revised pages of the Supplement-EZ Form.
Understood
10. 1x hard copy & 1x electronic copy of the updated calculations.
Understood
11.2x hardcopies & 1x electronic copy of the updated plan sheets.
Understood
12. 1x hard copy (2x hard copies for plan sheets) & 1x electronic copy of anything else
needed to address the above comments.
Understood
Hard copies should be mailed to me at the following address:
For FedEx/UPS:
Jim Farkas
512 N. Salisbury Street, Office 640M
Raleigh, NC 27604
For USPS:
Jim Farkas
1612 Mail Service Center
Raleigh, NC 27699-1612
Hand Delivery:
Please reach out to me prior to hand delivering a submission to make sure that I (or
someone else in my group) will be able to receive the submission. Do not leave the
package in the foyer with the security guard.

2537E. LYON STATION RD, STE 102
DESIGN (& PO BOX361
ENGINEERING, RLLC CREEDMOOR, NC27522
919 230-0996
CLIENT -FOCUSED • COMPREHENSIVE • COST-EFFECTIVE
NOTE: Hard copies should not be sent to a Regional Office. Doing so will delay the
review process and the submission package may be lost while being sent from the
Regional Office to me in the Central Office.
Understood
C3 Design & Engineering, PLLC sincerely appreciates the opportunity to respond to these
comments and looks forward to discussing them with you further as needed. Please don't
hesitate to contact me with any further questions or comments you may have.
Regards,
Joel H. Sain, EIT
C3 Design & Engineering, PLLC
ioelPc3designeng.com