GC 3102

GENERAL CERTIFICATION FOR BANK STABILIZATION PROJECTS INCLUDING
PROJECTS ELIGIBLE FOR CORPS OF ENGINEERS NATIONWIDE PERMIT NUMBER 13
AND REGIONAL PERMIT 197800080
This General Certification is issued in conformity with the
requirements of Section 401, Public Laws 92-500 and 95-217 of the
United States and subject to the North Carolina Division of Water
Quality Regulations in 15A NCAC 2H, Section .0500 and 15A NCAC 2B.0200
for the discharge of fill material to waters as described in 33 CFR
3 3 0 Appendix A (B ) (13 ) of the Corps of Engineers regulations ( i . e .
Nationwide Permit No. 13) and Regional Permit 197800080. The category
of activities shall include any fill activity for bank stabilization
as long as impacts to waters or significant wetlands are minimized.
This Certification replaces Water Quality Certification (WQC) Number
1663 issued on September 8, 1983; WQC No. 1272 issued November 10,
1978; and WQC No. 2665 issued on 21 January 1992. This WQC is
rescinded when the Corps of Engineers reauthorize Nationwide Permit 13
or Regional Permit 197800080 or when deemed appropriate by the
Director of the DWQ.
The State of North Carolina certifies that the specified category
of activity will not violate applicable portions of Sections 301, 302,
303, 306 and 307 of the Public Laws 92-500 and 95-217 if conducted in
accordance with the conditions set forth.
Condit ions of Certification
1. Proposed bank stabilization greater than or equal to a total
of 500 linear feet (152.5 meters) in length requires
written concurrence from the Division of Water Quality as
long as the project complies with all conditions of this
General Certification;
2. Proposed bank stabilization less than 500 feet (152.5
meters} in length does not require written concurrence from
the Division of Water Quality as long as all the following
conditions are met;
3. Methods of bank stabilization (such as bioengineering) are
preferred rather than installation of riprap along extensive
stretches of streambank. Information about these methods is
attached;
4. That appropriate sediment and erosion control practices
which equal or exceed those outlined in the most recent
version of the "North Carolina Erosion and Sediment Control
Planning and Design Manual" or "North Carolina Surface
Mining Manual" (available from the Division of Land
Resoruces at the DEHNR Regional and Central Offices) are
utilized to prevent exceedances of the appropriate turbidity
water quality standard (50 NTUs in streams and rivers not
designated as trout waters by DWQ; 25 NTUs in all saltwater
classes and all lakes and reservoirs; 10 NTUs in DWQ-
classified trout waters);
5. All sediment and erosion control measures placed in wetlands
or waters shall be removed and the natural grade restored
after the Division of Land Resources has released the
project;
6. That the riprap shall be of such a size so as not to be able
to be carried off by wave or current action and consist of
clean rock or masonry material free of debris or toxic
pollutants. Riprap shall not be installed in the streambed

unless required for velocity control and approved by the
Division of Land Resources;
7. Measures shall be taken to prevent live or fresh concrete
from coming into contact with waters of the state until the
concrete has hardened;
8. If an environmental document is required, this Certification
is not valid until a FONSI or ROD is issued by the State
Clearinghouse;
9. That additional site-specific conditions may be added to
projects proposed under this Certification in order to
ensure compliance with all applicable water quality and
effluent standards;
10. Concurrence from DWQ that this Certification applies to an
individual project shall expire three years from the date of
the cover letter from DWQ.
Non-compliance with or violation of the conditions herein set
forth by a specific fill project shall result in revocation of this
Certification for the project and may also result in criminal and/or
civil penalties.
The Director of the North Carolina Division of Water Quality may
require submission of a formal application for individual
Certification for any project in this category of activity, if it is
determined that the project is likely to have a significant adverse
effect upon water quality or degrade the waters so that existing uses
of the wetland or downstream waters are precluded.
Public hearings may be held for specific applications or group of
applications prior to a Certification decision if deemed in the
public's best interest by the Director of the North Carolina Division
of Water Quality.
Effective data: 11 February 1997.
DIVISION OF WATER QUALITY
By
A. Preston Howard, Jr. P.E
Director
GENCERT.13
WQC # 3102

BIOENGINEERING METHODS attachment to General Certification for
Streambank Stabilization - NwP 13)
Alternatives to riprap
Root wads (along with b-8 feet of tree trunk) from hardwood trees have been used by the
N,C. Wildlife Resources Commission in various projects for stabilization in rural areas and by other
consultants in urban areas. Root wads are installed into the eroding bank and anchored by rocks or
rebar. By the time the root wads rot out, native vegetation is replaced. Tag alder, buttonbush and
willow are frequently used as plantings among the root wads.
Brush layering consists of laying willow cuttings (several feet in length) horizontally,
with the branch tips toward the stream and rooting end away from the stream. Soil is piled on top of
the cuttings and several more layers are installed. When installed during a dormant period (winter or
fall), growth should occur the following spring. Dormant cuttings may be inserted in the banks or in
spaces in between the synthetic product (if used) for bank stability. Black willow is a good species to
use for bioengineering since it will root easily and grows well in the eastern U.S.
Riprap may be used when necessary to protect the outer toe of meanders. Rip rap should
be placed on the outside curves from the toe to bank full height, Bank full is considered to be the
highest point that the water level typically reaches on a yearly average. Bank full can sometimes be
detected by sand deposits or a change in vegetation.
A-jacks are a new tool which were used in the Rocky Branch restoration demonstration
(NCSU) and were placed in the outside curves of the eroded stream bank. A-jacks are 6-legged
concrete structures which interlock and can be stacked as a pyramid. A-jacks are used in combination
with coconut husk fibers which are soaked and compressed and made into logs. These logs are used
at the toe of the slopes and are placed so that they overlap the A-jacks. Plants can be planted directly
into these logs and which will biodegrade in .5-7 years after which plants have stabilized the area.
Used in this manner, A-jacks are much more stable than rip-rap.
Lunkers are another stabilization device which are elongated bench-like structures that are
open on 3 sides allowing waters to flow through them, while also providing fish habitat. They can be
made of recyclable material (plastic) or of oak.
Gabions are a hard structural form consisting of a wire basket filled with rip-rap type
stone. They are very durable and can be used in areas of high velocity to reduce the energy from
wave action without impacting downstream hydraulics.
Vegetative pl~anti'ngs
Bioengineering methods in conjunction with native plantings can be used to produce
aesthetically pleasing, biologically diverse streams. The use of native vegetation is desirable since
native species are non-invasive and they reduce velocity, protect banks from scour and have root
systems which create bank support. Vegetation also contributes organic matter and provides shade to
protect aquatic life. Shading helps reduce water temperatures and enables higher levels of dissolved
oxygen to be held in water.
In addition to establishing bank vegetation for shading, plantings should be placed on the
erosional side (or outside curve) of streams where velocity is greatest. Vegetative plantings dissipate
erosive forces and hold sediment in place. Plants most effective for bank stabilization have deep roots,
low growth forms, dense branching patterns and are resilient under pressure such as flooding. It is
desirable to have at least a 25 foot width of bank vegetation where feasible.
When replanting of banks is required, there should initially be the linear equivalent of 400
trees per acre or as specified in the planting plan - i.e., on 10 foot centers. Survival after five years
shall be far a total of 320 stems (80% survival rate) or its equivalent, Trees planted should be large
enough (several feet in height) to ensure that they won't be scoured away during adverse weather.