The design standards outlined in this article
shall be utilized by developers, surveyors, and engineers in preparing
subdivision plans, and will be applied by the Board of Lawrence Township
Supervisors when reviewing plans for approval. These standards shall
be considered as minimum standards for the developer to comply with
in the design, development, and improvement of a subdivision. Where
strict compliance with the standards is clearly impractical due to
site conditions, the Township Supervisors may modify the standards
to permit reasonable utilization of the property while securing substantial
compliance with the intent and purpose of these regulations.
A.
Sites with moderate slopes are preferable to either
very steep or very level land. Improvement costs and erosion potential
increase sharply on sites with slopes over 10%, and very level land
presents problems with on-site sewage disposal and stormwater drainage.
B.
Existing natural features such as trees and watercourses
which would add value to residential developments shall be preserved
in the design of a subdivision as conservation measures.
C.
Land located within a flood hazard area shall not
be subdivided for any use which may endanger life and/or property,
or aggravate a flood hazard. Development in flood hazard areas must
comply with the rules and regulations of the National Flood Insurance
Program, other state floodplain regulations, and the Township's Floodplain
Ordinance (Ord. No. 93-1 of 1993).[1]
A.
Lots located within the one-hundred-year floodplain
shall be subject to the following:
(1)
Any lot created or revised shall have no more than
50% of its area within the floodplain, with the exception that large
lots may be exempted provided a minimum of one acre of said lot is
outside the floodplain.
(2)
Lot access to a public road shall not be restricted
or prevented by floodplain areas.
B.
If the Board of Township Supervisors determines that
only a portion of the proposed plan can be safely developed, they
shall limit development to that part and shall require the developer
to proceed in accordance with this determination.
C.
When the developer does not intend to develop the
plan himself and the Township Supervisors determine that additional
controls are required to ensure safe development, the Township Supervisors
shall require the developer to impose appropriate deed restrictions
on the land. Such deed restrictions shall be inserted on every deed
and noted on every recorded plan.
D.
All construction within the floodplain area must be
completed in accordance with all Township and state floodplain regulations.
[Amended 3-16-2010 by Ord. No. 2010-02]
Subdivision and land development plans shall include measures
that direct stormwater into the natural drainage system serving the
area. The following standards shall apply to stormwater drainage within
Lawrence Township:
A.
Lots shall be laid out and graded to provide positive drainage away
from buildings. The Township may require a grading and drainage plan
for individual lots indicating a buildable area within each lot, complying
with the setback requirements, for which positive drainage is assured.
B.
No person, corporation, or other entity shall block, impede the flow
of, alter, construct any structure in, deposit any material or thing
in, or commit any act which will affect normal or flood flow in any
communal stream or watercourse without having obtained prior approval
from Lawrence Township or the Department of Environmental Protection,
whichever is applicable.
C.
Where a subdivision or land development is traversed by a natural
watercourse, there shall be provided a drainage easement or right-of-way
conforming substantially with the line of such watercourse and of
such width as will be adequate to preserve natural drainage.
D.
The Township will ensure that all permanent streams not under the
jurisdiction of other official agencies are maintained, open and free
flowing.
E.
The subdivider or developer, and each person, corporation, or other
entity which makes any surface changes in excess of 5,000 square feet,
shall be required to prepare and submit a stormwater management plan
for review and acceptance by the Township Engineer. The stormwater
management plan shall be in accordance with any Township stormwater
management ordinance and shall contain provisions for the following:
(1)
Collecting on-site surface runoff and disposing of it at the point
of discharge into the common natural watercourse of the drainage area;
(2)
Drainage facilities to handle runoff from upstream areas;
(3)
Drainage structures and facilities as are necessary to prevent erosion
damage to the subdivision or land development, adjacent property and
downstream property. Such structures and facilities shall satisfactorily
convey surface waters to the nearest practical street, storm drain,
detention pond, or natural watercourse.
F.
Storm sewers, culverts, and/or related installations shall be provided
to permit unimpeded flow of natural watercourses, to drain all low
points along streets and to intercept stormwater runoff along streets
at intervals reasonably related to the extent and grade of the area
drained.
G.
Storm sewers, when required, shall be placed in front of the curb
or curbline when located in a street right-of-way. When located in
undedicated land, they shall be placed within an easement not less
than 15 feet wide, as accepted by the Township Engineer.
H.
Street drainage will not be permitted to cross intersections or the
crown of the road.
(1)
Maximum spacing of street inlets shall not exceed 600 feet.
(2)
All street inlets shall be PennDOT Type C or M. Inlet tops shall
be cast-in-place reinforced concrete or precast concrete.
(3)
All culvert ends shall be provided with either reinforced concrete
headwalls or pipe end sections.
(4)
Minimum pipe size shall be a fifteen-inch diameter.
(5)
When material for a storm drain is not specified, PennDOT specifications
will govern.
I.
All springs and sump-pump discharges shall be collected so as not
to flow onto any cartway.
J.
Stormwater roof drains shall not discharge water directly over a
sidewalk.
K.
Stabilized outlets shall be provided for drains and downspouts.
L.
The Soil Cover Complex Method of the Natural Resources Conservation
Service (NRCS) of the U.S. Department of Agriculture and the Rational
Method are the acceptable means of estimating stormwater runoff and
for designing or analyzing stormwater management facilities. The actual
method for each subdivision and land development shall be determined
and directed by the Township Engineer.
M.
Where the estimated runoff based upon the above methods is doubtful,
several recognized methods should be studied and compared.
N.
The minimum design criteria for ditches, swales, driveway cross pipes
and storm sewers shall be designated using the Rational Method and
shall be sized to accommodate a ten-year, five-minute design storm
unless otherwise approved by the Township Engineer. Drainage ditches,
swales, etc. shall be of sufficient depth to accommodate driveway
cross pipes and pipe culverts.
O.
Runoff calculations must include complete hydrologic analysis for
pre- and post-development conditions and hydraulic design and analysis
of all control facilities. The analysis shall be performed for two-,
ten-, twenty-five-, and one-hundred-year-year storm frequencies. This
shall include, but not necessarily be limited to: rating curves, and
stage-storage and routing computations for stormwater management facilities.
P.
Control facilities shall adhere to the following and/or any Township
stormwater management ordinance:
(1)
Permanent control measures/facilities shall be designed to ensure
that the maximum rate of stormwater runoff is not greater after development
than prior to development. Detention and retention basins shall have
a spillway to protect the berm by precluding overtopping. The spillway
capacity shall, at a minimum, be capable of handling the one-hundred-year
storm while providing two feet of freeboard. More stringent criteria
may be required in sensitive areas where stormwater problems presently
exist.
(2)
Control facilities shall be designed to meet, at a minimum, the design
standards and specifications of the Erosion and Sedimentation Control
Handbook for Clearfield County.
(a)
Detention ponds may not be required by the Township on the recommendation
of the Township Engineer at sites in close proximity to the major
streams, provided that computations are prepared and submitted for
review and comment. Said computations shall demonstrate that no increase
in peak rates of runoff will result from the proposed activity for
the specified storms.
(b)
Detention ponds shall be prohibited in areas of known sinkholes
unless the pond is lined. If a sinkhole develops in a pond or channel
before acceptance by the municipality, a lining shall be required.
(c)
All detention ponds shall be provided with a fence of a type
and height subject to approval of the municipality and shall be designed
to ensure access for maintenance.
(d)
All detention ponds shall be provided with a suitable access
road as approved by the Township.
(3)
On-lot subsurface detention facilities (seepage pits, etc.) shall
be used to the extent practicable in minor subdivisions subject to
the acceptance of the Township Engineer. Roof drain seepage pits must
provide at least one cubic foot of storage volume for every two square
feet of roof area. Roof drain seepage pits shall be located at a minimum
of 10 feet from any structure, shall have a maximum depth of four
feet and shall include provisions for emergency overflow to prevent
property damage.
(4)
A maintenance program for control facilities must be included as
part of the stormwater management plan.
(a)
Maintenance during development activities of a project shall
be the responsibility of the contractor, developer, and owner.
(b)
Permanent ownership and continuing operation and maintenance
of all proposed stormwater control facilities shall be consistent
with the following principles:
[1]
If a development consists of structures or lots which are to
be separately owned and in which streets, drainage facilities and
other public improvements are to be dedicated to the municipality,
stormwater control facilities should also be dedicated to and maintained
by the municipality.
[2]
If a development site is to be maintained in single ownership
or if drainage facilities and other required improvements are to be
privately owned and maintained, then the ownership and maintenance
of stormwater control facilities should be the responsibility of the
owner or private management entity.
[3]
The Township Supervisors, upon recommendation of the Township
Engineer, shall make the final determination on the ownership and
continuing maintenance responsibilities prior to final approval of
the stormwater management plan. The governing body reserves the right
to accept the ownership and operating responsibility for any or all
of the stormwater management controls.
A.
All streets proposed for public use on the final plan
shall comply with the following design specifications:
|
Street Type
|
Minimum Right- of-Way Width
(feet)
|
Minimum Cartway Width
(feet)
|
Minimum Sight Distances at Intersections
(feet)
|
Maximum Grade
|
Minimum Grade
| |
|---|---|---|---|---|---|---|
|
Local
|
50
|
20
|
200
|
7%
|
0.5%
| |
|
Collector
|
60
|
24
|
300
|
7%
|
0.5%
| |
|
Major
|
(PennDOT requirement)
|
30
|
400
|
6%
|
0.5%
|
B.
These specifications may be superseded by state design
specifications. Additionally, the Township Supervisors may increase
the minimum widths and sight distances where deemed necessary in order
to ensure public safety.
A.
Streets shall conform to any plans and official maps
which have been prepared and adopted by the state or by the Board
of Lawrence Township Supervisors.
B.
Streets shall be appropriately related to the topography
of the land in order that lots and streets may have acceptable grades.
C.
Local streets shall be designed to discourage use
by through traffic, but provisions for street connections to adjacent
areas will be required where deemed necessary. Where connections are
to be made, the proposed street system shall extend existing or recorded
streets at the same right-of-way and cartway widths, but in no case
at less than the required minimum widths.
D.
Half-streets shall be prohibited except to complete
an existing half-street in an adjacent tract.
E.
Where a subdivision borders on or contains an existing
or proposed major street, the Township Supervisors may require marginal
access streets, rear service alleys, reverse frontage lots and/or
screening in order to protect bordering lots, reduce the number of
intersections with the major street, and separate local and through
traffic.
F.
Areas reserved for future street extensions into adjoining
tracts must be shown on the plans and be designated for this purpose.
No building lots may utilize these areas as their only public access.
These areas shall not be dedicated to public use until the streets
are extended into an adjoining tract.
G.
No dead-end streets are permitted without an adequate
turnaround.
H.
The finished excavation of proposed streets located
within the one-hundred-year floodplain shall be no more than two feet
below the regulatory flood elevation. The Township Supervisors and/or
Clearfield County Conservation District may require, where necessary,
profiles and elevations of streets to determine compliance with this
requirement. Drainage openings shall be sufficient to discharge flood
flows without increasing flood heights.
B.
Adequate turnarounds shall be provided at the closed
end of a permanent cul-de-sac street. Turnarounds shall be constructed
to the specifications of the design which shall be approved by the
Township.
C.
Any road with a temporary dead-end which has been
authorized through approved stage development shall be provided with
a suitable all-weather turnaround. The use of such turnaround must
be guaranteed to the public. It shall be the responsibility of the
developer to properly remove the turnaround and repair its area when
the street is extended unless the design is compatible with future
street extensions. These removal and repair requirements shall apply
to both temporary and permanent culs-de-sac when street extensions
are proposed.
A.
Streets shall be designed to intersect as nearly as
possible at right angles. Streets shall not intersect at an angle
of less than 70° or more than 110°.
B.
Intersections involving the junction of more than
two streets shall be avoided.
C.
Clear sight triangles of 100 feet measured along local
street center lines from their point of junction shall be provided
at all intersections, and no building nor obstruction shall be permitted
within such sight triangles. (See Appendix, Exhibit No. 5.[1])
[1]
Editor's Note: The Appendix material to this
chapter is on file in the Township offices.
D.
Intersections with major streets shall be located
not less than 800 feet apart, measured from center line to center
line.
E.
Streets intersecting from opposite sides with a common
street shall be designed either directly opposite one another (four-way
intersection) or with a minimum offset of 200 feet between their center
lines.
G.
Intersections shall be designed with a flat grade
wherever deemed practical by the Township Supervisors. The approach
to any intersection shall have a leveling area which has no greater
than a two-percent grade at a distance of 60 feet from the nearest
right-of-way line of the intersecting street.
A.
Private drives may be permitted only when they serve
not more than two separate lots that have no other access to a public
road. The original tract will not be counted as one of the two separate
lots if the tract utilizes the private drive for access.
B.
The right-of-way width of a private drive shall be
50 feet. The Township Supervisors may permit widths less than 50 feet
if it is impossible to reserve this right-of-way area within the property.
All private drive rights-of-way must be surveyed, and bearings and
distances must be shown on the plan drawings. The plan must note that
the street(s) is/are private and that Lawrence Township has no obligations
for maintenance.
C.
The cartway width and construction specifications
must be agreeable to the developer, lot owners who utilize the private
drive, and the owners of any properties which contain the right-of-way.
Proof of this agreement must be submitted to the Board of Township
Supervisors.
D.
The following maintenance requirements shall be incorporated
as conditions for final approval. These conditions shall be placed,
in writing, on the final plan, or attached thereto, and shall be part
of the property deed(s).
(1)
Each lot owner having a right to use the private drive
shall be equally responsible for the maintenance of the street, and
such maintenance responsibilities shall be listed in a maintenance
agreement.
(2)
The maintenance agreement shall run with the land
and with any future conveyance of the property. The agreement shall
be incorporated in and made part of the conveyance binding on the
parties, their successors and assignees.
(3)
The Township of Lawrence shall not accept any responsibility
for the maintenance of a private drive.
E.
There shall be no further subdivision of any lot served
by a private drive until such time as public streets are constructed
to serve the lots.
B.
Blocks shall have sufficient width to provide for two tiers of lots of appropriate depth in accordance with the lot size requirements in § 107-30.
C.
At the discretion of the Township Supervisors, public
crosswalk easements of at least 10 feet in width shall be provided
in blocks exceeding 1,000 feet to facilitate pedestrian access to
shopping areas, schools, playgrounds, parks and other community facilities.
B.
The Township Supervisors may require that the minimum
size of residential lots be increased when compliance with the Pennsylvania
Department of Environmental Protection regulations warrant such increase.
C.
The depth of a lot shall not exceed twice the width
unless waived by the Township Planning Commission and Board of Township
Supervisors. Such a waiver would be considered in the Township's best
interest to avoid landlocking otherwise usable land. However, in no
event shall the depth of the lot exceed three times its width after
the waiver is granted.
D.
Side lot lines shall be substantially radial or at
right angles to street lines.
E.
Every lot in a subdivision shall front on a dedicated
or public street, unless a private drive has been approved by the
Township Supervisors.
A.
Easements for utilities shall have minimum width of
10 feet. Before determining the exact location and width of easements,
the developer shall discuss his plan with the local public utilities
to assure the proper location of easements for the installation of
such service.
B.
Where possible, easements shall be centered on or
adjacent to rear or side lot lines. They shall be drawn only to the
edge of the street rights-of-way and shall not be shown on the right-of-way.
C.
Where a subdivision is traversed by a watercourse,
drainage channel, or stream, there shall be provided a drainage easement
conforming to the line of such watercourse and of such width as will
be adequate to preserve natural drainage.
If the developer proposes to reserve an area
for public use (i.e., schools, parks, other neighborhood and public
facilities), the following standards shall be applied to the character,
extent and location of the reserved area:
A.
Such areas shall be labeled on the plan as "reserved,"
and shall indicate the particular type of public use for which the
area is being reserved.
B.
Areas reserved for public use shall be accessible
through frontage on a public street and/or pedestrian rights-of-way
at least 10 feet in width, and be a suitable size and location for
their designated uses.
C.
The developer must establish and assure the future
ownership of the permanent, public use, as well as indicate the provisions
for the maintenance of the area. Additionally, the Township may accept
the dedication of such land or any interest therein for public use
and maintenance.
