08RW0270February 27, 2008 BS
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STAFF' S
REQUEST ANALYSIS
AND
RECOMMENDATION
08RW0270
BB Hunt, L.L.C.
Matoaca Magisterial District
North of Brandermill Parkway (State Route 1921),
West of Charter Colony Parkway (State Route 754), and West of Clemons Way (State Route
7172) and East of Little Tomahawk Creek
REQUEST: Board of Supervisors approval of an exception to the requirements of Section 19-
232 of the Chesapeake Bay Preservation Ordinance relating to Resource
Protection Area Regulations. Specifically, the applicant is requesting an
exception to encroach into the Resource Protection Area (RPA) as a result of the
proposed construction of a constructed wetland for stormwater treatment for the
existing residential subdivision Charter Colony. Exceptions to the Resource
Protection Area Regulations are permitted pursuant to Section 19-235 (b)(2) of
the Ordinance.
GENERAL INFORMATION
Develo er:
Daniel T. Schmitt & Timothy D. Vaughan
BB Hunt, L.L.C.
T ,ncati nn
The property is identified as 900 Agee Terrace and located within the Little Tomahawk
Creek drainage basin. The project limits are within the Charter Colony development;
east of Little Tomahawk Creek adjacent to the intersection of Clemons Way (State
Route 7172) and Clemons Circle (State Route 7173), Tax ID 724-701-0806 (Sheet 5).
Providing a FIRST CHOICE community through excellence in public service
Existin.~ Zoning
Single-Family Residential - R9
Existing Land Use and Condition of Resource Protection Area:
The proj ect area is a single lot residential subdivision, Charter Colony -Sedwick Village.
The proposed limits of clearing and grading for the construction of the stormwater
facility is along the forested riparian buffer and generally outside the flood plain
associated with Little Tomahawk Creek. The majority of the area to be cleared is
between two existing sewer easements. The vegetation in the area of the proposed
project is a fragmented semi-mature forest consisting mostly of saplings and shrubs.
Area of Proposed RPA Encroachment:
The area of disturbance for this proposed project will impact approximately 2.15 acres of
which 7547 ft2 (0.17 acres) is in existing RPA. The area of encroachment results from
the proposed grading, to construct a wetland for treatment stormwater runoff.
BACKGROUND
The developer for the residential development Charter Colony - Sedwick Village has requested
an exception for potential impacts to lands within designated Chesapeake Bay Preservation
Areas (CBPAs) and associated downstream water bodies. CBPAs, which include Resource
Protection Areas (RPAs) and Resource Management Areas (RMAs), are present on the subject
property. Those stream segments determined to have perennial flow must adhere to the county's
Chesapeake Bay Preservation Ordinance (CBPO). The CBPO requirements of the Zoning
Ordinance specify that a RPA be established adjacent to perennial water-bodies, to include
connected and contiguous wetlands, and consist of an undisturbed 100-foot natural vegetative
area. In order to meet the zoning, development and site requirements, the applicant has
requested an encroachment into the 100-foot RPA buffer to allow for the development of a
constructed wetland for stormwater treatment.
The request comes in part due to the resistance from federal regulatory agencies to the county's
regional in-stream stormwater treatment facilities. The county subsequently requested the
applicant, BB Hunt, provide for voluntary stormwater retrofits to improve water quality. The
proposed constructed wetland is in response to this request. A water quality impact assessment
(WQIA) and request for exception is required of the applicant regarding the potential impacts to
CBPAs and downstream water bodies. A discussion of both documents follows.
ANAT VCTC
A. To approve a Chesapeake Bay Preservation Ordinance (CBPO) exception request, the Board
of Supervisors must determine whether the proposed development is consistent with the
Ordinance and the applicant satisfies the six (6) findings, outlined below, as required by
Section 19-235 (b)(1).
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The Applicant addressed these findings as part of the application process. The Applicant
position can be found attachment Document A.
1. The requested exception is the minimum necessary to afford relief.
The proposed constructed wetland will provide stormwater treatment for a portion of the
original drainage area for a proposed regional BMP which met resistance with federal
agencies. The constructed wetland would be partially located within the RPA buffer to
maximize its treated drainage area (5.3 acres); avoid a potential utility conflict and
topographic constraints. The encroachment into the seaward 50-foot RPA buffer has been
avoided for protection of the adjacent stream.
2. Granting the exception shall not confer any special privileges upon the applicant
that are denied by this division to other property owners who are subject to its
provisions and who are similarly situated.
Granting this exception will not confer any special privileges upon the applicant since the
original plan for this property included construction of a regional pond. The location of the
proposed constructed wetland was suggested by county staff in order to maximize the treated
drainage area while minimizing environmental impacts.
3. The exception request is in harmony with the purpose and intent of this division
and will not result in a substantial detriment to water quality.
The constructed wetland will provide pollutant removal to stormwater runoff from an area
where treatment via a regional BMP is no longer feasible. The proposed constructed wetland
in combination with the remaining seaward 50-foot buffer will provide more pollutant
removal than was previously provided by the buffer area alone.
4. The exception request is not based upon conditions or circumstances that are self-
created orself-imposed.
The applicant is not required to provide onsite stormwater management. The applicant is
proposing the constructed wetland at the request of county staff in an effort to provide
pollutant removal for an area that was intended to drain to a regional stormwater BMP.
5. Reasonable and appropriate conditions are imposed, as warranted, that will
ensure that the permitted activity will not cause a degradation of water quality.
During construction, erosion and sediment controls will be in place to protect Little
Tomahawk Creek and the remaining RPA buffer from erosion, sedimentation, and flooding
which may result during construction. Additionally, the constructed wetland will provide
greater cumulative water quality value than the intact 100-foot RPA buffer.
6. The request is being made because of the particular physical surroundings, use,
shape or topographical conditions of the specific property involved or property
3 08RW0270-FEB27-BOS-RPT
adjacent to or within 100 feet of the subject property, or a particular hardship to
the owner will occur, as distinguished fi^om a mere inconvenience, if the strict
letter of this division is carried out.
At the request of the county, the applicant has agreed to provide stormwater treatment where
feasible, while respecting the layout of the approved site plan. The location of the proposed
constructed wetland was selected to maximize treatment. The basin is proposed to encroach
into the landward 50-feet of the RPA. The presence of utility lines and topographic
constraints (bedrock) prevent the relocation of the facility outside of the RPA buffer.
B. A water quality impact assessment (WQIA) required pursuant to Section 19-232 (e) prepared
by the applicant has been submitted to and approved by the Department of Environmental
Engineering -Water Quality. The approved document Charter Colony - Sedwick Village
Stormwater Water can be found on file with the county. A complete description of the
mitigation measures are on pages 10 to 11 of that document. A summary of those measures
can be found in attachment Document B.
RECOMMENDATIONS
Staff finds that the WQIA and the project are consistent with the ordinance and the criteria as
outlined in Section 19-235 (b)(1) of the Chesterfield County Code for the Board of Supervisors
to consider Chesapeake Bay Preservation Ordinance (CBPO) exception requests. Staff,
recommends approval of this request as it pertains to the exception to the CBPO for Charter
Colony - Sedwick Village Stormwater Retrofit Plan project only. Furthermore, all other
recommendations listed therein shall be incorporated into the site plans for the project, which
must then receive final approval by Environmental Engineering. Any changes to the Plan of
Development that would cause any deviation from the items listed in the WQIA, either in the
form of increased impacts to components of the RPA or omissions of mitigation requirements
from the submitted Plan of Development must be reviewed and approved by the Chesterfield
County Board of Supervisors.
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DOCUMENT A
Applicant's response to the six (6 findin sg as required by Section 19-235 (b
REQUEST FOR AN EXCEPTION TO THE REQUIREMENTS
OF THE ZONING ORDINANCE
Charter Colony - Sedwick Village Stormwater
Tax ID# 724-701-0806 (Sheet 5)
A. Provide the justification for the proposed exception and a discussion of how each of the
following findings are met:
1. The requested exception is the minimum necessary to afford relief.
The requested exception is the minimum necessary to afford relief to the applicant in order to provide
stormwater management for the project in accordance with the Swift Creek Watershed Master Plan. The
proposed constructed wetland is located to the maximum extent practicable outside of the RPA buffer. It
was located partially within the RPA buffer in order to maximize its treated drainage area (5.3 acres)
while avoiding a potential utility conflict and topographic constraints. The proposed constructed wetland
will provide stormwater treatment for a portion of the original drainage area for a proposed regional BMP
which was rejected by the agencies due to impacts to waters of the U.S. including wetlands.
Encroachment into the seaward 50-foot RPA buffer has been avoided for protection of the adjacent
stream.
2. Granting the exception will not confer upon the applicant any special privileges that are denied to
other property owners who are similarly situated.
Granting this exception will not confer any special privileges upon the applicant since the original plan
for this property included construction of a regional pond which would impact a much larger portion of
the RPA buffer. According to Section 19-232 (a)(5) of the Chesterfield County Zoning Ordinance,
encroachments into the RPA buffer area may be allowed by the department of environmental engineering
for stormwater management facilities that treat water from a significant portion of a watershed. The
location of the proposed constructed wetland was suggested by County staff in order to maximize the
treated drainage area while minimizing environmental impacts.
3. The exception request is in harmony with the purpose and intent of the Chesapeake Bay Preservation
requirements of the Zoning Ordinance.
The exception request is in harmony with the purpose and intent of the Chesapeake Bay Preservation
requirements of the Zoning Ordinance. The ordinance permits encroachments into the RPA buffer for
stormwater management facilities that treat water from a significant portion of a watershed. The proposed
encroachment into the RPA buffer has been minimized by the applicant to the maximum extent
practicable. The constructed wetland will provide pollutant removal to stormwater runoff from an area
where treatment via a regional BMP is no longer feasible. The proposed constructed wetland in
combination with the remaining seaward 50-foot buffer will provide more pollutant removal than was
previously provided by the buffer area alone.
4. The proposed exception is not based upon conditions or circumstances that are self-created or self-
imposed.
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The proposed exception is not based upon conditions or circumstances that are self created or self
imposed. The applicant is not required to provide onsite stormwater management, rather is proposing the
constructed wetland at the request of County staff in an effort to provide pollutant removal for an area that
was intended to drain to a regional stormwater BMP.
5. Reasonable and appropriate conditions have been imposed that will prevent the allowed activity from
causing a degradation of water quality.
During construction, erosion and sediment controls will be in place to protect the area of Little
Tomahawk Creek and RPA buffer from erosion, sedimentation, and flooding which may result from the
proposed constructed wetland. In addition to silt fence along the downslope side of the disturbed area
within the RPA buffer, a diversion dike, sediment trap and soil stabilization blankets are planned as
additional erosion and sediment control measures. The proposed mitigation in the form of creation of the
constructed wetland will provide greater cumulative water quality value than the intact 1 o0-foot RPA
buffer. The proposed constructed stormwater wetland will remove approximately 1.13 lb/yr of Total
Phosphorus (TP), which exceeds the required level of treatment for stormwater management purposes.
6. The request is being made because of the particular physical surroundings, use, shape or
topographical conditions of the specific property involved or property adjacent to or within 100 feet of
the subject property, or a particular hardship to the owner will occur, as distinguished from a mere
inconvenience, if the strict letter of this division is carried out.
The proposed site plan for Sedwick Village was approved with all stormwater management provided by
the County regional BMP, thus no onsite stormwater management is required. However, at the request of
the County, the applicant has agreed to provide stormwater treatment where feasible, while respecting the
layout of the approved site plan. The location of the proposed constructed wetland was selected to
maximize treatment. The basin is proposed to encroach into the landward 50-feet of the RPA and because
the presence of utility lines and topographic constraints (bedrock) prevent the relocation of the facility
outside of the RPA buffer.
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DOCUMENT B
The outline below summarizes those measures submitted as part of the WQIA for
the mitigation of the encroachment and water quality improvement.
The following is a list of mitigation measures for the proposed encroachments to the RPA.
These measures will provide additional stormwater treatment and water quality
benefits/improvements. The remaining environmental features will be protected during
construction by maintaining erosion and sediment control standards, and after construction, by
increased vegetative buffer and informative signage along the remaining RPA.
The following will be included as part of the construction plans:
1. Erosion and sediment control standards of the county will be maintained during all phases of
the construction process.
2. The creation of the constructed wetland to provide greater water quality value than the intact
100-foot RPA buffer. The proposed constructed stormwater wetland will remove
approximately 1.13 lb/yr of Total Phosphorus (TP), which exceeds the required level of
treatment for stormwater management purposes.
3. Additional vegetative riparian buffer in the form of a constructed wetland will be established
adjacent to the RPA buffer to increase natural infiltration, which acts as an additional
environmental resource protection measure.
4. Education Materials:
• Educational signs detailing the location of riparian buffer areas.
• Development of a stormwater management guidance document specific to the
constructed wetland operation and maintenance.
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