8C-1-1 Intent:

The Watershed Management District (WMD) is established to provide for the protection of water quality and the proper management of stormwater resources in the Lake Pelham-Mountain Run Lake Watershed. The WMD is created to promote the public health, safety and welfare by protecting the public water supply and minimizing the potential of pollution and degradation of the supply of drinking water for Town and County residents. The WMD is also established to ensure the management of stormwater to enhance the flood-control capability of the lake system and assure adequate reserve capacity and longevity of the Lake Pelham Reservoir. The WMD shall provide for protection of the watershed and its headwaters through minimum disturbance of the land, restriction of stormwater pollution and avoidance of water quality degradation. In addition, the groundwater capabilities of the watershed shall be protected to provide for aquifer recharge as the sole alternate to surface water drinking supplies.

8C-1-2 Findings of fact:

8C-1-2.1 It is the aim of this district to provide regulations that will apply within the designated watershed, as adopted by the County Comprehensive Plan and in accordance with the Lake Pelham-Mountain Run Lake Watershed Management Plan and its implementation policies, to respond to the unique conditions and special circumstances presented there and prevent the further or future deterioration of associated water resources. This watershed has been identified as a sensitive resource that requires exceptional means and careful planning to avoid compromising the stormwater and lake reservoir system and its public benefits.

8C-1-2.2 The public interest is best served by protecting the capabilities of the watershed for current and future residents and preventing the deterioration of water quality. As a limited resource, the lake system is subject to accelerated degradation from development and human activity that could create a public health liability, severely restrict the usefulness of the resource and/or produce significant public cost to restore, if possible.

8C-1-2.3 Therefore, these regulations are promulgated to protect these interests, avoid adverse effects and ensure the continued viability of watershed resources.
(Ord. of 3-3-1992, § 8C-1)

(Ord. of 3-3-1992, § 8C-2)

Every development in the watershed shall be subject to the additional regulations contained in this Article. An evaluation of proposals will be required for evaluating the resulting downstream impact to avoid and/or mitigate those impacts so as to protect the water quality and restrict future degradation of the watershed. It is incumbent on the applicant to demonstrate that the public interest will be upheld and that protection of the public drinking supply will be preserved. Development shall be regulated to protect watershed resources to every extent practicable.

8C-3-1 Environmental Impact Assessment (EIA):

Every development in the watershed shall be accompanied by an EIA that assesses the off-site impacts of stormwater generated from the proposal; before-and after-development water quality loadings; the affect of slopes, soils, wetlands, and other natural features; prospective BMP's and effect on stream/lake loadings; and consideration of alternatives to the proposal. The County may require implementation of a comparable alternative development layout if it is found to be superior in providing water quality protection. The EIA shall present mitigation measures for identified impacts and, where acceptable to the County, include them in the development plan as a condition of approval.

8C-3-2 Watershed management plan and policies established:

8C-3-2.1 The Watershed Management Plan (Espey, Huston and Associates, Inc.; September 1989) and Policies (adopted into the Comprehensive Plan; January 1990) are hereby incorporated as a part of this Article to identify critical elements of the watershed, establish analytical criteria and assure the protection of water quality. The Plan identifies:

a.

Watershed boundary.

b.

Critical lakes, streams and tributaries.

c.

Drainage basins.

d.

Buffer areas for critical watercourses.

e.

Proposed wet pond sites for consolidated stormwater management.

f.

Restrictions on overall development by drainage basin.

g.

Identification of critical sewer/water service areas around Lake Pelham.

8C-3-2.2 The Plan and Policies shall be used to review development proposals and establish limits of loadings within each drainage basin in the watershed.

8C-3-3 Cluster development preferred:

8C-3-3.1 The use of cluster development for residential uses is preferred, with required open space to be used for buffering critical watercourses and avoiding environmentally sensitive areas that can compromise downstream resources. Sensitive environmental areas include steep slopes, lake and stream banks and highly erodible soils.

8C-3-3.2 Any cluster development shall decrease in intensity of use as the distance from the identified stream/water body buffer decreases. This decreasing density shall be established by creating imaginary five hundred (500) foot bands around the buffer and then establishing the density of each band, diminishing in intensity as the buffer is approached. If it can be shown that proposed BMP's or natural features of the land, such as topography, will better serve to protect water quality, this requirement may be waived. Where development is part of a PUD, nonresidential uses shall be limited to commercial activity that is supported by the development and no more than ten percent (10%) of the tract.

8C-3-4 Development limitations:

The WMD establishes overall limits to development within each drainage basin, in accordance with the Watershed Management Plan, to avoid overloading the capacity of each basin and prevent eventual stream/lake degradation. Each basin contains density limits which represent a maximum for any one (1) development [i.e.: ten (10) dwelling units per acre]. Nonresidential development other than parks, churches, and community facilities shall be limited. New areas for nonresidential use are not prohibited but are discouraged. All nonresidential development is subject to density limitations which coincide with the residential limitations. [For the purpose of exchange, two thousand (2,000) square feet of non-residential floor area is equivalent to a dwelling unit].

8C-3-5 Buffers required:

8C-3-5.1 Development in the WMD shall require buffering around lakes, on each side of streams and along tributaries. All buffers shall be left in their natural vegetative state or improved with suitable landscaping so as to increase the stormwater and pollutant/nutrient reduction capabilities of the buffer. General maintenance of such buffers, including removal of undesirable species, is permitted as long as the integrity of the buffer is maintained. In accordance with the Watershed Management Plan, required watercourse buffers shall be defined as a minimum distance from the watercourse as follows:

a.

Lake Pelham and Mountain Run Lake: Two hundred (200) foot minimum from normal pool elevation [384.9 feet elevation, Lake Pelham; 434.0 feet elevation, Mountain Run Lake].

b.

Primary streams and wet ponds: One hundred (100) foot minimum from the flood way or the normal pond pool.

c.

Identified tributaries: Fifty (50) foot minimum from the center line of the watercourse.

8C-3-5.2 No future development, construction or introduction of impervious surface shall be allowed in the buffer, other than road crossings, passive recreation and utilities, subject to demonstration that no reduction in the quality of the buffer shall occur. Uses specifically prohibited in the buffer include septic systems and drainfields, feed lots (i.e., finishing cattle for slaughter), fuel or petroleum storage, sewer pump stations, etc. Detention ponds and dams may be located in the buffer. Additional buffer will be required around a pond.
(Ord. of 3-3-1992, § 8C-3)

8C-3-6 Lake Pelham-Mountain Run Lake Watershed Restrictions: The Lake Pelham-Mountain Run Lake Watershed serves the Lake Pelham reservoir which is a public water supply for Town and County residents and provides the surface water recharge for the lake. The watershed has been shown to be sensitive to certain development activities and susceptible to impacts from particular uses that may affect water quality. The lakes are subject to degradation from hazardous substances that may gain entry by spill, surface runoff or groundwater leachate. As a result, the following uses and storage thereof are prohibited in the watershed as part of any non-residential activity:

8C-3-6.1 Hazardous materials and wastes.

8C-3-6.2 Flammable or combustible substances and the storage of more than one hundred (100) gallons or fifty (50) pounds of such substances.

8C-3-6.3 Toxic wastes and substances.

8C-3-6.4 Bulk and underground storage.

8C-3-6.5 Landfills and debris sites.

8C-3-6.6 Storage or land spreading of sludge.

In addition, sewer treatment plants and other uses for which a NPDES or VPDES permit is required for more than one thousand (1,000) gallons of effluent are also prohibited, excluding stormwater management facilities.

(Ord. of 5-7-2013(2))

8C-4-1 BMP's required:

8C-4-1.1 Every development shall require some form of best management practices (BMP's) to mitigate watershed impacts and limit on-site effects. Each development is required to select and implement the most appropriate BMP for dealing with stormwater runoff and protection of water quality. BMP's may include, but are not limited to, wet or dry ponds, filter strips along roads and drives, limits to site grading, early vegetative cover, spoil pile stabilization, grass swales for drainage channels, hydroseeding of graded areas and other techniques as suggested by the Commonwealth of Virginia State Water Control Board Urban Best Management Practices Handbook, most current edition.

8C-4-1.2 Best management practices shall be reserved solely for the identified purpose for as long as the County requires and adequate provision made for maintenance. Easements may be required for any BMP included in a development proposal and the area in wet or dry ponds must be dedicated to such use and recorded prior to finalization of any subdivision or site plan. Adequate assurance of maintenance and future transfer to a legal responsible entity must be provided as a condition for approval. Golf courses shall be required to develop a nutrient management plan that demonstrates that the fertilizers and pesticides will be contained on-site and will not impact the off-site surface water or groundwater resources.

8C-4-2 Disturbed area, impervious surface:

8C-4-2.1 Development in the WMD shall be limited to minimize land disturbance and reduce the potential of downstream degradation. Each site or parcel of land shall be restricted as to the total area of disturbance and the creation of impervious, nonporous surfaces to inhibit erosion, reduce runoff and impede the off-site impact of development in the watershed. Generally, the area of total disturbance of the land for roads/drives, utilities, structures, parking and activity space shall not exceed forty percent (40%) of the tract at any one (1) time, excluding wet ponds and BMP's. Porous pavement, while not considered impervious surface, is considered disturbed area. Areas of land disturbance shall be so noted on plats and site plans for review and visibly identified in the field for inspection. Future site development must include any unstabilized areas resulting from previous disturbance and its cumulative effect on proposed disturbed areas.

8C-4-2.2 The maximum allowable impervious surface area for nonresidential development shall be twenty-five percent (25%) of the tract. Residential subdivisions shall be limited to a maximum of fifteen percent (15%) impervious surface for each lot and twenty-five percent (25%) of the entire tract for subdivision development. Clustered development shall not be limited by lot as long as the maximum impervious surface for the entire tract does not exceed twenty-five percent (25%). Nonresidential subdivisions shall be subject to twelve and five-tenths percent (12.5%) maximum impervious surface for interior roads.

8C-4-2.3 Exemptions for Commercially Zoned Properties.

Property zoned commercial prior to March 3, 1992 shall be exempt from meeting the requirements of Section 8C-3-4, Section 8C-4-2.1 and Section 8C-4-2.2 provided the applicant meets the requirements of Section 8C-4-2.3.

The site development plans shall meet the requirements set forth by the Virginia State Department of Conservation and Recreation (DCR) Handbooks for Stormwater Management and Erosion and Sediment Control.

A water quality analysis shall be performed using the performance based calculation criteria outlined in Chapter 5Section 10 of the DCR Stormwater Management Manual. The baseline (pre-development) phosphorous loading shall be calculated using a rate forty-five hundredths (0.45) pounds per acre per year (lbs/ac/yr) or sixteen (16) percent impervious cover if using the simple method calculation procedure. Post development phosphorous loading shall be calculated using the simple method calculation equation: L = 2.28*A*[0.05 + (0.009*I%)] where A equals site area and I% equals impervious percentage. Post development loadings shall be reduced to baseline loading though conventional and innovative best management practices (BMP's).

Downstream natural channels shall be analyzed for adequacy to convey the developed condition of a two-year peak discharge within the channel banks and at a non-erosive velocity. In addition, man made channels are to be analyzed for adequacy to convey the ten-year peak discharge within the channel banks and the two-year peak discharge at a non-erosive velocity. All man made channels shall be stabilized immediately and prior to being made operable. When a channel is determined to be not adequate, a stormwater detention BMP shall be sized to discharge the two-year and ten-year frequency developed-condition peak discharge at the respective pre-developed rates. (VADCR 2-2.2)

Land disturbance sequencing shall adhere to the specifications outlined in section 8C-4-2.1 unless the applicant demonstrates to the plan approving authority that land disturbance in excess of forty (40) percent of the tract area at any given time is required to balance the site or construction cannot otherwise be accomplished. Accordingly, when land disturbance exceeds forty (40) percent of the tract area, the state specified minimum design wet and dry storage volume for sediment traps and basins shall be doubled to allow for increased settling time. Perimeter erosion and sediment control shall be provided using diversion berms and not silt fence. All areas must be stabilized immediately upon reaching final grading and the application of sod is highly encouraged.

If the proposed site development activities exceed sixty (60) percent impervious cover or seventy (70) percent site disturbance then Low Impact Development (LID) analysis and plan shall be prepared for review. The LID plan shall include site design checklist, LID calculation worksheets, and details of LID practices. The LID plan shall promote groundwater recharge, provide the required pollutant removal, and maintain the pre-development time of concentration, peak runoff rate and runoff volume.

A preliminary layout plan and stormwater management plan shall be submitted and approved by Culpeper County prior to submittal of the site plan. As-built plans for all permanent BMP's shall be required and the maintenance of such facilities shall be established prior to bond release.

8C-4-3 Erosion and sediment control plans:

Every development is required to file an erosion and sediment control plan in accordance with Chapter 8 of the Culpeper County Code and the Virginia EandS Control Handbook, most current edition. Development in the WMD that disturbs five thousand (5,000) square feet or more of land area shall comply with this regulation except agricultural activities as exempted by state law.

8C-4-4 Utility services:

Municipal sewer services shall be encouraged in sensitive areas of the watershed around Lake Pelham. Drainage Basins GR, HR, LP6 and LP7 are included in Phases I and II; LP2, LP3, LP4, LP5, BB, VB and MR1 are all included in Phase III. Development in Phases I and II should be coordinated to coincide with the implementation of municipal services rather than septic systems. All other utilities and service methods shall be in accordance with Chapter 14, the Sanitary Code of Culpeper County. Package plants identified in section 14-20 are prohibited.

8C-4-5 Exclusions, credits and bonuses:

8C-4-5.1 Any property which is shown on a site plan or subdivision plat to be engineered so as not to drain into Lake Pelham, directly or indirectly, shall not be considered to be regulated by the WMD, notwithstanding its depiction on the Official Map, as long as the subsequent development is in accordance with such plan or plat.

8C-4-5.2 If, in the opinion of the Board of Supervisors, it is good planning practice to do so, where land lying within the watershed is under common ownership and is adjacent to or part of a tract proposed for development, the use of which is limited to park, open space or passive recreation, such land can be utilized in establishing the density, impervious surface and disturbed area for the development. Limitation of use must be guaranteed for all intents and purposes by permanent easement.

(Ords. of 3-3-1992, § 8C-4; 7-5-2005(2); 5-7-2013(2))

8C-5-1 Farm plans:

All agricultural operations in the watershed shall be encouraged to exercise conservation measures and agricultural BMP's. Such operations are required to file a farm plan with the Soil and Water Conservation District that meets the intents and objectives of this Article, including required buffers and other pertinent practices as guided by the Soil and Water Conservation District.

8C-5-2 Agricultural hardship:

This Article shall not prevent the Planning Commission from providing an exception to agricultural operations that would otherwise be compromised by these regulations. These cases are recognized as special hardships that, while required to conform to this Article to further the public purpose, shall not be significantly impaired or restricted from the agricultural use of their property.
(Ord. of 3-3-1992, § 8C-5)

8C-6-1 Existing parcels:

Proposals for subdivision or site plan approval which have proceeded to the level of public hearing (having been approved by the Planning Commission and/or Board of Supervisors) shall be vested with regard to lot size, density and the other regulations of this Article other than the requirements for buffering, impervious surface or erosion and sediment controls. Any future site plan or subdivision of the property must fully comply with the regulations contained in this Article. A (Agricultural), R (Residential), or RA (Rural Area) zoned lots that preexist the adoption of this Article are considered vested with regard to lot size only. Commercial and industrial properties are vested only with regard to allowable uses. All existing structures are fully vested.
(Ord. of 6-12-1996)

8C-6-2 Site plan exceptions:

8C-6-2.1 In any case or request for a site plan on a parcel existing on March 3, 1992 and on which the zoning has not changed since that date, in which the applicant claims or can produce evidence that the use of his property will be negatively affected as opposed to the use allowed prior to the enactment of this Article, the Planning Commission may, for good cause shown, at its option and at the request of the applicant, reduce the required buffering on any given parcel so affected. Upon request, the applicant shall present a proposed buffering plan as an alternative to the Code requirements. The Planning Commission may adopt this plan or impose other requirements related to the protection of the watershed.

8C-6-2.2 In any case or request for a site plan amendment on a developed parcel existing on March 3, 1992 and on which the zoning has not changed since that date, the density limitations contained in section 8C-3-4 may be waived by the Planning Commission if the total impervious surface on the site is not increased, and if the intent of the Watershed Management District is not compromised.
(Ord. of 10-6-1998)

Editor's note— Amendment of 10-6-1998 moved purview regarding site plan exceptions to the Planning Commission, rather than the Board, modified section 8C-6-2.1 so as to clarify the applicable date, and added section 8C-6-2.2.

8C-6-3 Building permit exceptions:

In any future case or request for a building permit for a zoned lot of record existing at the time of the adoption of this Article and which contains less than ten (10) acres, the zoning administrator shall have the authority to deviate from the buffering requirements imposed by this Article, upon presentation by the applicant for the permit or the landowner, as the case may be, that the strict application of the buffering requirements will so adversely impact on the applicant or owner so as to prevent the owner from utilizing the property in a reasonable manner. Upon request, the applicant shall present a proposed buffering plan as an alternative to the Code requirements. The zoning administrator may accept this plan or suggest other requirements related to the protection of the watershed. Any decision by the zoning administrator made pursuant to this section may be appealed to the Board of Supervisors, to be treated as it would treat a request made pursuant to Subsection 8C-6-2, above.
(Ord. of 3-3-1992, § 8C-6)