Water Supply Watershed Buffer Disturbances
General Information
Water supply watershed buffers were the first buffers established for the protection of water
quality in Charlotte-Mecklenburg. The purpose of these buffers is to protect water quality
conditions in the drinking water supply reservoirs in the Catawba River, including Lake Norman,
Mountain Island Lake and Lake Wylie. These buffers do not have multiple zones with varying
levels of allowable disturbances as do the more recently adopted buffer rules and generally water
supply watershed buffers are considered to be “undisturbed” although some minimal disturbance
is allowed.
Exempt Disturbances in Water Supply Watershed Buffers
Provided below are the disturbances that are considered to be exempt from the water supply
watershed buffer requirements. These activities can be performed without prior authorization
and do not require mitigation for the buffer impact. All disturbed land surfaces in the buffer
must be stabilized using an effective groundcover.
1. Public projects such as roads and bridges.
2. The limbing of trees up to half the distance of their height.
3. The removal of dead trees.
4. Minimal hand clearing of small undergrowth and removal of trees two (2) inches in
caliper or smaller measured six (6) inches above the root ball.
5. The addition of new trees and/or shrubs.
Potentially Allowable Disturbances in Water Supply Watershed Buffers
The following disturbances are potentially allowable requiring prior approval in the form of an
“Authorization Certificate” from Charlotte-Mecklenburg Storm Water Services as well as
possible mitigation. If any of these activities result in the removal of existing trees greater than
2-inch caliper measured six (6) inches above the root ball, then Level 2 revegetation authorized
by Charlotte-Mecklenburg Storm Water Services is required. All disturbed land surfaces both
inside and outside the water quality buffer must be stabilized using an effective groundcover.
1. Removal of damaged or diseased trees larger than two (2) inch caliper measured six (6)
inches above the root ball that could potentially fall and damage a structure.
2. Removal of invasive species.
3. Stream bank or shoreline stabilization and dredging approved by Duke Energy.
4. Pathways that adhere to the following Pathway Guidelines:
• Pre-approval of all pathways by Charlotte-Mecklenburg Storm Water Services is
required prior to installation.
• Pathways should meander through the buffer avoiding trees and minimizing
environmental impact.
• Openings for pathways should not exceed four (4) feet in width.
• Only one (1) pathway is allowed per residential lot.
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Pathways should take the most direct route from the house to the water or pier to
minimize disturbance.
Pathways must be made of pervious materials such as mulch or sand. Pathways
made of concrete, asphalt, pavers, rock or gravel are not allowed in buffer.
Slatted boardwalks are allowed provided boards are spaced at least ¼ inch apart
and the ground beneath the boardwalk is comprised of pervious material. In
addition, no trees can be cut or damaged during installation and the width must be
no more than 3 feet at any location.
On occasion, minor buffer disturbances are requested such as the installation of flag poles, signs,
security lights and other new structures that result in a very minimal increase in impervious
cover. In such cases, approval may be granted by a supervisor or the program manager with
Charlotte-Mecklenburg Storm Water Services on a case-by-case basis outside the normal review
process. For such situations, approval can be granted by email without the submittal of an
application or approval of mitigation.
Prohibited Disturbances in Water Supply Watershed Buffers
The following disturbances are prohibited in the water supply watershed buffer.
1. Installation of permanent structures and/or built upon areas, including but not limited to
septic tank systems, sidewalks, patios, gazebos, brick or concrete walls and out buildings.
Pervious asphalt, concrete, any type of gravel and pavers are also considered “built-upon
area” and cannot be placed in the buffer.
2. Grading, clearing or filling in the buffer.
3. Installation of ponds or structural Best Management Practices (BMPs).
4. Piping of roof drains or other drainage through the buffer. All storm water pipes must
stop prior to the buffer and discharge as sheet flow.
5. Planting turf grass.
6. Installation of impervious pathways.
Any variation from the above requires a variance from the Zoning Board of Adjustment for the
jurisdiction where the disturbance is proposed. A buffer disturbance in violation of the above
criteria and in the absence of a variance is considered illegal and will require restoration. The
exception is with the buffer rules for Lower Lake Wylie in the City of Charlotte, which includes
provisions for preapproval by staff of buffer impacts in the event of a legitimate “hardship” and
following approval of a mitigation plan. Three (3) mitigation techniques are allowed, including
Buffer Restoration, Buffer Preservation and Mitigation Credits.
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