20211518 Ver 1_12-7-2021 DWR Comment Response_20211207

DWR Comment Response
Page 7 of the PCN carries the signature of R. Daniel Hyatt. In order for R. Daniel Hyatt to sign,
the application package requires an agent authorization letter from the applicant. The agent
authorization letter must be signed by the landowner. Please review the PCH Help Document
page 10 for more information. A sample agent authorization letter can be found attached. [15A
NCAC 02H .0502(a)(11)]. See Agent Authorization Form attachment.
The plan proposes to place the stream in a 48" culvert and re-route the culvert under Richland
Street. The plan also calls to plug and abandon the existing CMP that flows under Richland
Street onto PIN 8615-17-7729. Please show the offsite location of the proposed rerouted 48"
culvert and outlet on your site plan. [15A NCAC 02H .0506(b)(1)]. See Sheet C2.1 for new layout
of culvert. The proposed culvert will connect to the existing storm culvert that is on the site. A
small portion of existing pipe will be removed to allow for proposed culvert to be installed.
Sheet C3.0 describes the installation process and pump around that will occur to allow for the
proposed culvert to be connected to the existing culvert.
3. Please locate all existing wetlands, streams, and other waters of the State as overlays on the
site plan. [15A NCAC 02H .0502(a)(9)] See Sheet C0.2, jurisdictional wetlands and streams are
labeled.
4. As indicated under Item C.3.g (Page 13) of the USACE PCN Complete Help File "The stream
impact length should be measured along the centerline of the stream. When proposing a
culvert, the impact length is generally greater than the length of the culvert and associated
dissipater since the existing stream usually has some sinuosity (curvature)." Please verify or
correct the stream impact length as indicated on the PCN form. Please provide updated
drawings and application materials (including Table of Impacts in the PCN form) that properly
show the length of impacts to the jurisdictional stream. [15A NCAC 02H .0502(a) and (c)](a)(9)].
See updated stream table and plan sheets. The corrected stream impact length is 188 feet.
Please provide a detail showing how the proposed culvert will meet condition II. 11 of DWR's
GC 4256, which corresponds to USACE NWP 29, for culvert burial. "Placement of culverts and
other structures in streams shall be below the elevation of the streambed by one foot for all
culverts with a diameter greater than 48 inches, and 20% of the culvert diameter for culverts
having a diameter less than or equal to 48 inches, to allow low flow passage of water and
aquatic life." This requirement should also be included in the Stream Crossing Installation Notes
on Sheet C3.0. [15A NCAC 02H.0506(b)(1) and .0502(a) and (c)]. See sheet C3.0 for detail.
6. In order to show your project will be in compliance with Condition 17 in GC 4256, please
provide a detail showing the proper installation (below the streambed elevation) of the
proposed riprap pad at the culvert inlet. [15A NCAC 02H .0502(a) and (c)]. See sheet C3.0 for
detail.
7. Please update the PCN impact table to include the temporary stream impacts for dewatering
the channel to install the culvert (pump -around sequence). [15A NCAC 02H .0502(a) and (c)].
See attached updated stream impact table.

Please update the PCN impact table to include the proposed headwall and rip rap at the culvert
inlet as a permanent impact. Any rip rap added below the ordinary high-water line is considered
a permanent impact. [15A NCAC 02H .0502(a) and (c)]. See attached updated stream impact
table.
DWR recommends against the use of reinforced concrete pipe for the stream crossing as it is
unlikely to hold stream substrate and provide for aquatic organism passage. If reinforced
concrete pipe is used for the stream crossing and fails to hold stream substrate, DWR will
require the culvert be modified with a sill, or similar structure, to hold stream substrate. [15A
NCAC 02H .0506(b)(3)]. See sheet C2.1 for pipe material (CMP).
10. DWR recommends against the use of smooth walled HDPE material for the stream crossing as it
is unlikely to hold stream substrate and provide for aquatic organism passage. If HDPE pipe is
used for the stream crossing and fails to hold stream substrate, DWR will require the culvert be
modified with a sill, or similar structure, to hold stream substrate. [15A NCAC 02H .0506(b)(3)].
See sheet C2.1 for pipe material (CMP).