The primary purpose of the Open Space Conservation
District (OSC) is to preserve open land, sensitive natural, scenic
and historic areas and rural community character that would be lost
under conventional development. In addition, it is the intent of this
district to permit a reasonable amount of residential development
in the form of small, compact neighborhoods of single-family detached
homes in an open space setting, located and designed to reduce the
perceived intensity of development, preserve natural resources and
scenic vistas and provide privacy and neighborhood identity. Specific
objectives are as follows:
A. To provide an effective means of responding to site
conditions for the preservation of steep slopes, woodlands, stream
valleys, floodplains and wetlands.
B. To preserve scenic vistas and elements of the Township's
rural character by minimizing views of new development from existing
roads.
C. To provide for the creation, retention and protection
of open space in the Township.
D. To encourage innovation and promote design flexibility,
efficiency and ingenuity in the siting of singe-family detached homes
and their accompanying infrastructure.
E. To require less impervious surface than necessary
with conventional development, reduce erosion and sedimentation associated
with earth disturbance, reduce pollutants from surface water runoff
and maintain high levels of groundwater recharge.
F. To provide an opportunity to attain the objectives
of the Township's Comprehensive Plan and Open Space, Recreation and
Environmental Resources Plan with regard to open space preservation,
orderly growth and enhancement of environmental resources.
G. To provide for the enhancement of woodlands through
natural succession and reforestation, where appropriate, and to encourage
the preservation of habitat for various forms of wildlife.
H. To protect and preserve prime agricultural land, natural
and historic resources, the continued viability of agricultural security
areas and the continuity of development and viability of agricultural
operations.
[Added 6-25-2001 by Ord. No. 4-2001]
A building may be erected or used and a lot
may be used or occupied within the OSC Open Space Conservation District
only for a purpose permitted by right in the RU Residential District
and for the following uses:
A. Uses by right.
(1)
Singe-family detached dwelling.
(2)
Common open space areas. A development in this
District shall provide for common open space.
B. Conditional use standards for conventional development.
(1)
Authorization to develop a tract pursuant to the requirements of the underlying residential district (conventional development), rather than the Open Space Conservation District, may be granted by the Board of Supervisors as a conditional use pursuant to §
139-118.1, provided that the applicant follows the procedures and submits the information required below, proves conformance with the standards and criteria set forth in §
139-118.1 and, in addition thereto, establishes the following:
(a)
That conventional development will preserve natural and scenic features, historic sites and historic resources to a degree equal to or greater than development under the Open Space Conservation District. The applicant must submit sketch plans for both development under the Open Space Development option and the conventional development option in order to demonstrate compliance with this requirement. The applicant may be required to protect such features, sites and resources from further development with appropriate conservation easements running with the land. Where development of less than the entire parcel is intended or where the parcel is intended to be developed at less density than conventional development would permit, the applicant may be required to file a development plan for the entire parcel pursuant to §
123-17 of the Subdivision and Land Development Code or may be required to restrict further subdivision and/or development on the remainder of the tract by recorded conservation easement.
(b)
That the applicant has achieved the Open Space Conservation goals set forth in §
139-150 by conveyance of a perpetual conservation easement to a recognized nonprofit corporation established for that purpose or by any other means of facility ownership set forth in §
139-156.
(2)
The applicant shall comply with the procedures governing conditional use applications outlined under §
139-118.1 of this chapter.
(3)
The sketch plans to be submitted by the applicant
as part of a conditional use application shall include the following
items, at a minimum:
(a)
Tract data. A survey plan which identifies total
acreage of the tract, tract boundaries showing bearings and distances
and the ownership of the tract and all adjacent properties. The legal
limits of rights-of-way shall be shown, along with the limits of an
ultimate right-of-way.
(b)
Environmental data. A plan which identifies
the limits of designated floodplain areas, seasonal wet and alluvial
soil conditions, woodland areas and steeply sloped land in excess
of a slope of 15%.
(c)
Development data. Sketch plans which indicate
the proposed subdivision of the tract with sufficient data to prove
that the proposed layout will comply with all requirements of this
article and the Zoning, Subdivision and Land Development and Environmental
Protection Ordinances.
(d)
Means of access. A plan which identifies all
existing access-point/curb cuts, including but not limited to public
roads, along the frontage of the tract and for a distance of at least
500 feet east and west of the tract, and such other existing access-point/curb
cuts at a greater distance from the tract if such existing access-point/curb
cuts will in any way impact upon the traffic entering into and/or
exiting from the proposed development. The plan shall also show all
other public roads within 500 feet of the tract proposed for development
and all new access points or connections into the existing public
highway system proposed as part of the development plan.
(4)
In addition, the applicant shall submit the
following studies:
(a)
Traffic impact study. The applicant shall be
responsible for the preparation and cost of a traffic impact study.
Such study shall be prepared by a traffic consultant hired by the
applicant with the approval of the Township. The study shall enable
the Township to access the impact of a proposed development on the
highway network, to identify traffic problems associated with the
proposed development, to identify solutions and to present improvements
to be incorporated into the project design.
(b)
Community impact study. The applicant shall
submit a study which will sufficiently assess the impact the development
will have on the community and its level of public services and manner
in which negative impacts thereon shall be resolved by the applicant,
to enable the Board of Supervisors to ascertain if the proposed development
is capable of being serviced by the public services as proposed and,
further, to determine if the applicant has made reasonable effort
to minimize the negative impact of the development on such services.
The study shall include, at a minimum, a study of at least the following
services and facilities:
[1]
Fire protection. The impact the proposed development
will have on fire protection capability, including, but not limited
to, municipal water supply, pumping capacity and specialized equipment,
should be analyzed. The applicant must adequately demonstrate what
effect the proposed development will have on these factors and its
ability to meet any specialized needs so that the development will
not have any adverse impact on the public safety by adversely affecting
the fire protection capability available to the community including
the proposed development.
[2]
Solid waste. A study to determine what amount
of solid waste will be generated as a result of the development should
be analyzed. The study should identify what method will be used to
dispose of solid waste and what effort will be directed toward recycling
solid waste.
[3]
Historical. A study shall be made that determines
the location of historic properties and structures both on and within
500 feet of the site and the effect said development will have on
these properties and structures, and what effort the developer will
make to preserve such historic properties and structures. Determination
of historical significance and the treatment of all negative impacts
will be considered by the Township Historical Commission, with the
final decision on treatment resting with the Board of Supervisors.
[4]
Water. A study of the amount of water needed
for domestic and fire use shall be provided. The study shall indicate
the location of the source and anticipated pressure of the proposed
source. The applicant shall indicate willingness to pay for the cost
of improvements to a public water system if it is determined that
connection to said system is necessary.
[5]
Sewer. A study providing information on the
alternative methods of sewage disposal shall be provided. The developer
shall provide information on the estimated gallons per day of sewage
that will be treated by the proposed use(s).
(c)
Environmental impact study. A study shall be
prepared which surveys environmental information and which addresses
how these sensitive areas will be conserved and protected. This information
shall serve as a basis for designing the development which is responsive
to environmental conditions as provided in this article and the Environmental
Protection Ordinance.
(5)
Conditional use approval shall not be required
for a conventional development where the Board of Supervisors determines
all of the following criteria are met:
[Added 11-10-2008 by Ord. No. 4-2008]
(a)
The property within the proposed subdivision
is subject to a perpetual conservation easement subject to the requirements
of the Conservation and Preservation Easements Act, 32 P.S. § 5051
et seq., held by a qualified conservation organization.
(b)
The conservation easement provides for open
space that satisfies the minimum common open space requirements of
the Open Space Conservation District, except that the area subject
to the conservation easement need not be held in a tract or tracts
separate from the development area.
(c)
The property is being subdivided consistent
with and subject to the provisions of the conservation easement.
(d)
The subdivision and conservation easement limitations
are consistent with the overall goals and conservation objectives
of the Open Space Conservation District.
(e)
A supporting recommendation by the Planning
Commission is obtained.
(f)
The subdivision complies with all other ordinances
of the Township.
The following standards shall apply to development
in this district:
A. Parcel yield (number of lots or density). The maximum number of lots and/or dwelling units shall be determined by applying the standards in §
73-11.1 of the Willistown Township Environmental Protection Ordinance to the underlying zoning district. Density shall be no greater than that which the underlying zoning subdivision and environmental protection regulations would permit.
B. Common open space. Not less than 75% of the total
tract area shall be designated on the plan as common open space and
held in a tract or tracts separate from the development area.
C. Development area. The area(s) of the tract not designated
as part of the common open space shall be designated on the plan as
development area(s). Development areas are all areas not designated
as common open space and include, but are not limited to, building
areas, yards, driveways, sewage-releted mechanical facilities and
roads.
D. Perimeter setback. Structures shall be situated so
as to maintain a minimum setback from any tract property line of 100
feet. Where existing natural features of the site, including but not
limited to woodland areas, changes in topography, hedgerows or other
site characteristics results in the dwelling unit being completely
visually screened from the adjacent property and guaranties are provided
through the planning process that such features will remain undisturbed,
this setback may be reduced to 75 feet.
E. Area and height regulations.
(1)
Minimum lot size: 15,000 square feet.
(2)
Maximum lot size: one acre.
(3)
Maximum building coverage: 20%.
(4)
Minimum lot width: 75 feet.
(5)
Minimum front yard: 25 feet.
(6)
Minimum side yard: 10/25 feet aggregate.
(7)
Minimum rear yard: 25 feet.
(8)
Height. No building other than a farm building
shall exceed 35 feet in height.
(9)
Maximum impervious coverage:
[Added 5-14-2001 by Ord. No. 1-2001;
amended 6-4-2004 by Ord. No. 5-2004; 11-10-2008 by Ord. No. 4-2008]]
|
Lot Size
|
Percent
Impervious
|
---|
|
Less than 1/2 acre
|
30%
|
|
1/2 acre to less than 1 acre
|
25%
|
|
1 acre
|
20%
|
F. Access to common open space. All dwelling units shall
have access to common open space without the obstruction of intervening
lots, structures, fences or other impediments to pedestrians.
G. Historic sites and structures listed on the Township's Historic Resource Inventory. Historic sites and structures, including their cultural landscapes, may be included as part of the required common open space, subject to compliance with the requirements of this article. In addition, historic structures that are restored as single-family dwellings are not subject to inclusion in the parcel yield calculation determined pursuant to §
139-153A above. Reconstruction, alteration or restoration of historic structures shall conform to the current requirements of the United States Secretary of the Interior's Standards for Rehabilitation.
H. Cultural landscape delineation and protection. Cultural
landscapes required to preserve an historic site's integrity shall
be maintained. The Planning Commission shall delineate what areas
are to be included in the required cultural landscape.
I. Viewsheds, scenic vistas, scenic roads and significant visual landscapes. Dwellings and accessory buildings shall be configured so as to be located outside of broad, open vistas visible from roads or other public vantage points. In addition, such structures shall be located outside the immediate boundaries of scenic roads. See §
139-155 below for relevant design standards. Viewsheds, scenic vistas, scenic roads and significant visual landscapes are defined and inventoried in the Township's Open Space, Recreation and Environmental Resources Plan.
J. Natural resources. The applicant shall establish that development, including site improvement, lot design and open space configuration, preserves natural resources and environmentally sensitive areas in accordance with Chapter
73, the Willistown Township Environmental Protection Ordinance.
K. Landscaping buffering and screening. Natural areas or buffers shall be required for all proposed development in accordance with the requirements for the underlying zoning district pursuant to Article
X of the Willistown Township Environmental Protection Ordinance.
L. Detention, retention and sewage disposal areas. Traditional
stormwater management basins (detention basins) and sewage-related
mechanical facilities (grinder pumps, sand filters, etc.) are not
permitted in the common open space. Stormwater management facilities
or portions thereof that can be integrated into the natural environment
or which incorporate natural site features, such as swales. natural
retention ponds, filter strips, riparian buffers, etc., are permitted
to be located in the required common open space. Subsurface disposal
areas, spray irrigation disposal areas and sewage holding and settling
ponds with associated monitoring wells and equipment are permitted
to be located in the required common open space. Utility easements
may be included as part of the common open space. Easements satisfactory
to the Planning Commission shall be established to enable maintenance
of such facilities by the appropriate parties.
The location of common open space, dwellings and site improvements shall be in response to the inventory of site features and environmentally constrained areas required under Article
III, Conservation Plan Requirements, of the Environmental Protection Ordinance, and as otherwise regulated therein. The following standards
shall apply during the siting process:
A. Viewsheds, scenic vistas and significant visual landscapes.
(1)
Dwellings and accessory buildings shall be configured
so as to be situated below ridgeline elevations to preserve existing
scenic vistas. To achieve this objective, dwellings and accessory
buildings should be sited entirely below the elevation of the nearest
ridgeline whenever possible. Where the applicant claims that dwellings
or accessory buildings cannot be situated below the ridgeline, it
shall be the burden of the applicant to demonstrate why this is not
possible and how the proposed design creates the minimum possible
disturbance of views of the ridgeline. To the extent that any portion
of a structure must be located above a ridgeline elevation, such siting
shall be contingent upon the submission and approval by the Township
Planning Commission of a plan for the mitigation of such ridgeline
impacts. Such plans shall identify the locations and dimensions of
the proposed structure(s), the architectural style proposed and shall
demonstrate how the structure(s) shall be effectively screened from
adjacent tracts and/or designed to minimize disruption of views of
the ridgeline.
(2)
In addition, dwellings and accessory buildings
shall be configured so as to be located outside of broad, open vistas
visible from roads or other public vantage points as inventoried in
the Township's Open Space, Recreation and Environmental Resources
Plan.
B. Environmentally sensitive areas.
(1)
Dwellings and accessory buildings shall be configured
so as to be located outside environmentally sensitive areas, including
natural drainage swales. Specific requirements pursuant to the Township's
Environmental Protection Ordinance shall be considered.
(2)
In addition, applicants shall minimize disturbance
to valued woodlands and other vegetation consistent with the Township's
Environmental Protection Ordinance. Hedgerows and other vegetation
should be preserved and incorporated into the design of the site,
either as part of the open space or as buffers between residential
areas, roads and open space uses.
C. Scenic roads. Dwellings and accessory buildings shall
be configured so as to be situated outside the immediate boundaries
of scenic roads, as defined and inventoried in the Township's Open
Space, Recreation and Environmental Resources Plan. To achieve this
objective, dwellings and accessory buildings should be sited outside
the scenic road's visual corridor, whenever possible. Where the applicant
claims that dwellings or accessory buildings cannot be situated outside
the immediate boundaries of scenic roads, it shall be the burden of
the applicant to demonstrate why this is not possible and how the
proposed design creates the minimum possible disturbance of views
along the scenic road. To the extent that any portion of a structure
must be located within the scenic road's visual corridor, such siting
shall be contingent upon the submission and approval by the Township
Planning Commission of a plan for the mitigation of such impacts.
Such plans shall identify the locations and dimensions of the proposed
structure(s), the architectural style proposed and shall demonstrate
how the structure(s) shall be effectively screened from the scenic
road and/or designed to minimize disruption of views from the scenic
road. At a minimum, views of dwellings and accessory buildings from
scenic roads shall be minimized by the use of changes in topography,
existing vegetation or additional landscaping.
D. Development area(s).
(1)
Development areas shall consist of at least
five, but no more than 25 lots, and be surrounded by open land. Modifications
of this standard shall be permitted, provided that the applicant can
demonstrate to the Planning Commission's satisfaction that alternatives
are more appropriate for the tract in question and that such alternatives
are not being proposed solely for economic reasons. All lots within
development areas shall take access from interior roads, rather than
from roads exterior to the site.
(2)
Landscaping, buffering and screening of development areas pursuant to Article
X of the Willistown Township Environmental Protection Ordinance should consider the form of development proposed. For example, applicants proposing hamlet or village development with minimum street setbacks should plant deciduous street trees at forty-foot intervals on both sides of each street so that the community has a traditional and stately appearance upon tree maturity. Common areas, community greens and cul-de-sac islands should also be planted with native species of shade trees and flowering shrubs.
E. Street widths, culs-de-sac, curbs, sidewalks and paths. Pursuant to Chapter
123, as amended (the Subdivision and Land Development Ordinance), applicants are permitted to modify select street widths and corresponding cul-de-sac dimensions and waive curb and sidewalk requirements where it can be shown that the objectives of this article will be advanced and better development design is achieved.
F. Agricultural lands. Disturbance to prime farmland
soils and large tracts of contiguous land suitable for agricultural
use should be minimized. Where agricultural activities are anticipated,
setbacks or buffers should be utilized and the direction of prevailing
winds and drainage should be considered in the development design.
G. Sanitary sewers.
(1)
Land treatment technologies capable of recharging
groundwater aquifers are strongly encouraged. Subsurface disposal
areas, spray irrigation disposal areas and holding and settling ponds
should be functional designed and used as amenities for the tract.
For example, spray irrigation is particularly well suited to active
recreation areas which require occasional lawn watering. Holding and
settling ponds can be designed as natural lakes, adding aesthetic
appeal and value to the site.
(2)
Applicants proposing to develop lots of less than one acre utilizing community subsurface or spray irrigation systems may be eligible for a partial increase in density pursuant to Chapter
123, Article
VI, §
123-40A(4).
H. Stormwater management.
(1)
Stormwater management facilities (basins, wet
ponds, swales, etc.) should be integrated into their surroundings
to complement the natural character of the site. Well-designed facilities
are most effective when they are barely recognizable. Properly designed,
a stormwater facility may even be an asset to a site. In order to
properly integrate stormwater facilities into a site, careful consideration
must be given to their location, form and landscaping consistent with
the Townships Environmental Protection Ordinance. Applicants are strongly encouraged to consult the Pennsylvania
Handbook of Best Management Practices for Developing Areas, Spring
1998, for specific information regarding planning, use and maintenance
of BMP's.
(2)
Location is critical to the site design. Facilities
need not be hidden from view but should be integrated into the natural
contours of the site and located based on geologic, topographic and
soil conditions. Excessive grading, clearing of vegetation and alteration
of watercourses and wetlands should be avoided. As with sewage holding
ponds, stormwater facilities can serve multiple purposes, including
wildlife habitat areas, irrigation areas and scenic amenities. The
form of the facility should harmonize with the surrounding landscape.
Curvilinear forms are more appropriate to natural settings. Landscaping
consistent with the Township's Environmental Protection Ordinance,
helps blend the facility into the natural landscape.
I. Other applicable standards. The design standards of
the Township's Zoning and Subdivision and Land Development Ordinance concerning circulation, off-street parking, signs, lighting,
etc., shall apply to any development occurring under this article.
Ownership and maintenance of common open space shall be in accordance with §
139-108 of the Zoning Ordinance.
A management plan for the disposition, use,
maintenance and insurance of the common open space, including provisions
for funding, shall be provided to and approved by the Township Planning
Commission and Township Solicitor prior to plan approval. Management
plans shall include, at a minimum, the following components:
A. Executive summary. A brief summary of the contents
of the plan and a description of the open space to be managed. A description
of the form of ownership and insurance for the common open space.
B. Description of existing conditions. A brief but detailed
description of the site's resources and history, with emphasis on
the common open space. All resources should be discussed, including
the natural, scenic and historic resources of the site. Discussion
of natural resources should list species found on the site and the
overall condition and health of the natural system. Discussion of
the cultural and historic resources should include the significance
of the resource and its physical condition. Other resources should
be similarly discussed, including their relative health, condition
or significance.
C. Goals and objectives for the common open space. A
list of the overall goals and measurable objectives for managing the
common open space, including a description of the use(s) intended
for the common open space.
D. Management measures. A description of the actions, budget and schedule for managing and restoring the common open space pursuant to the goals and objectives described in Subsection
C above.
E. Maintenance and operation plan. A description of the
annual maintenance and operation of the common open space, describing
such things as mowing schedules, trail maintenance, invasive plant
removal measures, structure upkeep and other relevant activities.