§ 510 Natural Resource Mapping and Site Capacity Calculations.
   1.   All applicants for subdivision and land developments (major or minor) shall: (A) include maps delineating the natural resources and demonstrating compliance with Environmental Protection Standards in this Section, which may limit disturbance of natural features to the extent indicated in subsection .2.B(1) and (B) meet requirements of subsection .2.B(1). Lot line adjustments (subdivisions which will not result in the creation of an additional lot) shall be exempt from this requirement.
(Ord. 156, passed 4-27-2010)
   2.   The following natural resource and site capacity calculations shall be submitted by the applicant with applications for any of the following uses: B-4 Duplex Dwelling, B-5 Manufactured/Mobile Home Park, B-6 Apartments, B-7 Performance Subdivision, B-12 Single Family Detached Cluster, B-14 Townhouses, B-15 Twin House, B-16 Village House, and C-16 Continuing Care Retirement Community. In addition, the following natural resource and site capacity calculations shall be submitted by the applicant for any subdivision or land development involving a lot that had a site area of 10 or more acres within the AD Agriculture District or RP Resource Protection District, or 20 or more acres within WS Watershed District as of the effective date of this Ordinance.
   Through these calculations, the maximum number of dwelling units, the maximum amount of impervious surfaces, and the required amount of open space will be determined for the specific site, based upon the site’s specific characteristics.
   Where open space is required for resource protection, it shall be laid out to encompass the maximum amount of the resource that is to be protected that is practical. See § 603 .D concerning the required farmland lot for single-family detached dwellings in the AD District.
      A.   Base Site Area. Certain portions of tracts may not be usable for the activities proposed for the site. These areas shall therefore be subtracted from the site area to determine base site area.
(1)   Site area as determined by actual on-site survey
____ Ac.
(2)   Subtract - land that is not contiguous: i.e.:
   (a)   A separate parcel which does not abut or adjoin, nor share
   (b)   common boundaries with the rest of the development, and/or
   (c)   land that is cut off from the main parcel by an expressway,
   (d)   arterial or collector roadway, railroad, existing land uses, or
   (e)   major stream so as to serve as a major barrier to common use,
   (f)   or so that it is isolated and unavailable for building purposes.
   (g)   (Each parcel shall be treated separately for the purposes of
   (h)   Base Site area determination.)
____ Ac.
(3)   Subtract - land that in a previously approved subdivision was
____ Ac.
(4)   reserved for resource reasons such as flooding, or for recreation
____ Ac.
(5)   Subtract - land used or zoned for another use, i.e., land used or to be used for commercial or industrial uses in a residential development, or land in a different zoning district rather than the primary use.
____ Ac.
(6)   Subtract - land within ultimate rights-of-way of existing roads, or existing utility rights-of-way or easements.
____ Ac.
                              = BASE SITE AREA
____ Ac.
 
      B.   Resource Protection Land. All land and resources within the base site area shall be mapped and measured for the purpose of determining the amount of open space needed to protect them. Portions of a site that may have overlapping resource protection restrictions shall be subject to the highest open space ratio and shall be calculated only once.
Table of Natural Resource Protection Standards by District
Natural Resource Protection Standards
AD
WS or RP
RR or DD
VC or VR
PI or HC
Table of Natural Resource Protection Standards by District
Natural Resource Protection Standards
AD
WS or RP
RR or DD
VC or VR
PI or HC
100-year Floodplains
100%
100%
100%
100%
100%
Lakes and ponds
100%
100%
100%
100%
100%
Wetlands
100%
100%
100%
100%
100%
Streams and watercourses
100%
100%
100%
100%
100%
Slopes:
   15%–24%
20%
70%
70%
70%
70%
   25%–30%
30%
85%
85%
85%
85%
   over 30%
100%
100%
100%
100%
100%
Woodlands
50%
80%
70%
50%
40%
Carbonate Geology
***
***
***
***
***
Productive Agricultural Soils**
60%
0%
0%
0%
0%
**Protection shall be in accordance with § 509.2.J, § 602.D and the list of Productive Agricultural Soils in § 202.
***Shall comply with subsection .2.I.
 
         (1)   The applicant shall utilize the natural resource protection ratios for each resource from the preceding table and the acreage of each resource within the base site area to complete the following table. The percentages shall be converted into decimal places for the purposes of this Section. For example, a 20 percent protection standard shall be converted to 0.20 for use in this Section, and a 100 percent protection standard shall be converted to 1.0. This completed table shall then be submitted with any subdivision or land development plan, and shall be revised as necessary based upon review by the Township. The table shall be completed to the nearest 3 decimal places (such as 2.221 acres).
Resource
Natural Resource Protection Ratio for Resource from this subparagraph
Acres of Land in Resource
Acres of Resource Protection Land (Acres of Land in Resource multiplied by Natural Resource Protection Ratio)
Resource
Natural Resource Protection Ratio for Resource from this subparagraph
Acres of Land in Resource
Acres of Resource Protection Land (Acres of Land in Resource multiplied by Natural Resource Protection Ratio)
Floodplains
X   =
Lakes and Ponds
X   =
Wetlands
X   =
Streams and Watercourses
X   =
Steep Slope (15 to 24%)
X   =
Steep Slope (25 to 30%)
X   =
Steep Slope (Over 30%)
X   =
Woodlands
X   =
Productive Agricultural Soils
X   =
   Total Resource Protection Land in Acres
   =
 
         (2)   The applicant shall provide a plan showing the resource protected land calculated in accordance with subparagraph (1). The resource protected land shown on the plan shall remain as natural area and shall be preserved by one of the following means selected by the Board of Supervisors:
            (a)   Conveyance of a permanent conservation easement to the Township and/or a conservancy or other nonprofit corporation approved by the Township.
            (b)   Conveyance of the resource protected land to the Township where the area in which the resource protected land is located has been identified in the Township Comprehensive Plan, Watershed Plan or other Natural Resource Protection Plan as containing groundwater, riparian areas, forest, wildlife habitat or other natural resources of importance.
            (c)   Recording a declaration of covenants, conditions and restrictions in a form approved by the Township and containing such provisions as the Township deems appropriate to assure that the natural resource lands are preserved in accordance with the requirements of this Ordinance.
      C.   Recreation Land. The Township Subdivision and Land Development Ordinance may require the provision of a certain amount of land for recreation, and may offer an alternative of paying fees in place of providing recreation land. If so, the applicant shall provide calculations to show compliance with such provisions.
         (1)   Any minimum recreation land requirement may be met by portions of the open space on the tract if the applicant proves to the satisfaction of the Township that such areas are suitable for recreation purposes.
         (2)   If the required recreation land is not approved to overlap open space, or if open space is not required, and if no alternative is approved under the Subdivision and Land Development Ordinance, then the recreation land shall be provided on the tract in addition to any required open space.
      D.   Determination of Site Capacity. Individual site capacity net density, net buildable site area, and allowable impervious surface is calculated as follows for a residential development:
(1)   Take: resource protection land from subsection .2.B above
___ Ac.
(2)   Add: recreation land (unless Township allows a portion of the proposed preserved open space to count as recreation land)
___ Ac
(3)   Equals: resource protection plus recreation land
___ Ac
(4)   Take: base site area
___ Ac
(5)   Multiply: open space ratio (for the use/district) X
___ (Ratio)
(6)   Equals:
___ Ac
(7)   Whichever is larger, the acreage in (3) or (6) shall be the minimum required open space
___ Ac
(8)   Take: base site area
___ Ac
(9)   Subtract: minimum required open space–from (7) above
___ Ac
(10) Equals: net buildable site area =
___ Ac
(11) Take lot area of each lot
___ Ac
(12) Multiply: maximum impervious surface ratio (for use/district) X
___ (Ratio)
(13) Equals: allowable impervious surface for that lot =
___ Ac
(14) Take: base site area (from (4) above)
___ Ac
(15) Multiply (15) by maximum net density for the use/zoning district
(16) Refer to Article 6.X
___Du/Ac
(17) Equals: maximum allowable number of dwelling
(18) Units on the site =
___Du
*For the WS District, see § 602.B for calculation of density.
 
   3.   The following site capacity calculations shall be submitted with applications for agricultural, commercial, institutional, industrial, non-cluster single-family detached dwellings, and all other residential uses not regulated by subsection .2.
      A.   Base Site Area. Certain portions of tracts may not be usable for the activities proposed for the site. These areas shall therefore be subtracted from the site area to determine base site area.
(1)   Site area as determined by actual on-site survey
___ Ac
(2)   Subtract - land which is not contiguous: i.e.
   (a)   A separate parcel which does not abut or adjoin, nor share common boundaries with the rest of the development, and/or
   (b)   Land which is cut off from the main parcel by an arterial or collector roadway, railroad, existing land uses, or major stream so as to serve as a major barrier to common use, or so that it is isolated and unavailable for building purposes. (Each parcel shall be treated separately for the purpose of base site area determination.)
___ Ac
(3)   Subtract - land that was previously preserved by a conservation easement or a condition of an approved plan.
___ Ac
(4)   Subtract - land used or zoned for another use, i.e., land used or to be used for commercial or industrial uses in a residential development, or land in a different zoning district rather than the primary use.
___ Ac
(5)   Subtract - land within ultimate rights-of-way of existing roads, or utility rights-of-way or easements.
___ Ac
                              = BASE SITE AREA
___ Ac
 
      B.   Impervious Surface Ratio. Shall be calculated for each lot, based upon the lot area of each lot.
   4.   Suitability of Land. Where land is required to be set aside or protected for certain purposes, it shall be physically suitable for that purpose, and shall be arranged in a lot(s) that has a configuration that is suitable for that purpose. This includes, but is not limited to, protected agricultural soils, recreation land and required open space for resource protection. In the AD District, see the provisions for a farmland lot in § 603.D. Stormwater detention basins shall not count as meeting the minimum requirements for protected productive agricultural soils, recreation land or required open space for resource protection, unless specifically provided otherwise by this Ordinance. See the definition of “open space” in § 202.
(Ord. passed 10-2-2007, § 509; Ord. 156, passed 4-27-2010, § 36; Ord. 191, passed 1-8-2019)