[Ord. 691, 9/10/2009; as amended by Ord. 737, 1/19/2017]
For any of the regulated activities of this Part
4, prior to the final approval of subdivision and/or land development plans, or the issuance of any permit, or the commencement of any land disturbance activity, the owner, subdivider, developer or his agent shall submit a stormwater management plan for approval by the Board of Supervisors unless exempt under the provision of §
26-406. In addition to the requirement of this Part 4D, the plan shall meet the requirements of Title 25, Rules and Regulations of the DEP, Chapter 102, Erosion and Sediment Control, Chapter 105, Dam Safety and Waterway Management, and Chapter 106, Floodplain Management.
[Ord. 691, 9/10/2009]
The following items must be included in the stormwater management
plan:
A. Written report.
(1)
General description of project.
(2)
Feasibility analysis that evaluates the potential application
of infiltration, flow attenuation, bioretention, wetland or wet pond
BMPs, including rationale for those developments not intending to
use such facilities. Analysis shall provide:
(a)
General assessment of the anticipated additional runoff based on design storms and post-development condition and utilizing the calculation procedures required in §
26-426.
(b)
Indication of drainage areas on the development site resulting
in impervious, pervious, and rooftop runoff.
(c)
Indication of type of land use (residential, nonresidential)
generating the impervious surface runoff.
(d)
Delineation of soils on the site based on the Official Soil
Survey provided by the U.S. Department of Agriculture, Natural Resources
Conservation Service, Web Soil Survey (http://websoilsurvey.nrcs.usda.gov/)
and on-site soil study. Soil study shall be conducted by a soil scientist
and shall include sufficient probes/deep holes to evaluate application
of BMPs.
[Amended by Ord. 737, 1/19/2017]
(e)
Indication of soils generally suitable for infiltration and/or
wet pond/artificial wetland BMPs, including specification of those
soils requiring modifications.
(f)
Rationale for the decision to not proceed with implementation
of wet pond or artificial wetland BMPs such as insufficient soil suitability.
(g)
Rationale for not proceeding with infiltration-oriented BMPs in accordance with §
26-425, Subsection
3, of this Part
4.
(3)
General description of proposed stormwater management controls
and facilities both during and after development, including operation
and maintenance requirements for each facility and responsible party
for maintenance.
(4)
General description of erosion and sediment controls, including
those contained in any required erosion and sediment control plan.
(5)
Complete hydrologic, hydraulic, and structural computations
for all stormwater management facilities.
B. Maps.
(1)
Drafting standards:
(a)
The plan shall be drawn at a scale of one inch equals 100 feet
or greater.
(b)
Dimensions shall be set in feet and decimal parts thereof; and
bearings in degrees, minutes and seconds.
(c)
Each sheet shall be numbered and shall show its relationship
to the total number of sheets.
(d)
The plan shall be so prepared and bear an adequate legend to
indicate clearly which features are existing and which are proposed.
(e)
The boundary line of the subdivision or land development shall
be shown as a solid heavy line.
(f)
Plans shall be on sheets no smaller than 18 inches by 24 inches
and no larger than 30 inches by 42 inches.
(2)
General information:
(a)
Name or identifying title of project and tax parcel number (if
applicable).
(b)
Total acreage of the tract and area to be disturbed.
(c)
Name and address of the owner/applicant/developer, and name
and address of individual who prepared the plan.
(d)
A location map for the purpose of locating the site at a scale
not less than 800 feet to the inch showing the relation of the tract
to adjoining property and to all streets, roads and Township boundaries
existing within 1,000 feet of any part of the tract.
(e)
Plan date and date of latest revision to plan, North point,
graphic scale, and written scale.
(f)
Note on plan indicating any area that is to be offered for dedication.
(g)
Certificate, signed and sealed by an individual registered in
the Commonwealth of Pennsylvania and qualified to perform such duties,
indicating compliance with the provisions of this Part 4: "(Design
engineer), on this date (date of signature), has reviewed and hereby
certifies that the stormwater management plan meets all design standards
and criteria of the Warminster Township Stormwater Management Ordinance."
(h)
Statement on the plan acknowledging the stormwater BMPs and
management facilities to be a permanent fixture that can be altered
or removed only after approval by the Township of a revised plan which
shall be applicable to all future landowners.
(3)
Existing features:
(a)
Complete outline survey of the property to be subdivided or
developed shall be provided showing all courses, distances and area,
and tie-ins to all adjacent intersections.
(b)
The location, names and widths of streets, the location of property
lines and names of owners within 200 feet; the location of streams,
lakes, ponds or other watercourses outside the project area which
will be affected by runoff from the project.
(c)
The location, size, and ownership of all underground utilities
and services (e.g., wells, on-site sewage disposal systems), storm
drains, channels, and similar features within 200 feet of property
boundary, and any rights-of-way or easements within the property.
(d)
The location of existing buildings, streets and other significant
features within the property, the location and area of all floodplains,
forests, lakes, ponds, watercourses (including drainage swales), wetlands,
slopes 8% to 15%, steep slopes 15% to 25%, and very steep slopes 25%
or steeper.
(e)
Contours at vertical intervals of two feet, vertical intervals
of five feet for very steep slopes (greater than 25%).
(f)
An overlay showing soil types and boundaries and a statement
as to where the soils data was obtained. Overlay shall include a table
identifying each soil type, hydrologic soil group, construction limitations
and resolutions.
(g)
Stormwater management district boundaries and subwatersheds
applicable to the site.
(4)
Proposed features:
(a)
Proposed land use, total number of lots and dwelling units,
and extent of commercial, industrial or other nonresidential uses.
(b)
Locations and dimensions of all proposed streets, sidewalks,
lot lines, building locations, parking compounds, impervious and semi-impervious
surfaces (total area), sanitary sewer facilities, water facilities,
and areas proposed for public dedication.
(c)
Proposed changes to land surface and vegetative cover, including
areas to be cut or filled as shown on a plan for surface drainage.
(d)
Final contours at vertical intervals of two feet, vertical intervals
of five feet for very steep slopes (greater than 25%).
(e)
Plans and profiles of proposed stormwater management facilities,
including horizontal and vertical location, size, and type of material.
This information shall be of the quality required for the construction
of all facilities and include all calculations, assumptions, and criteria
used in the design of the facilities.
(f)
Construction detail(s) of all proposed stormwater management
facilities and appurtenances.
(g)
Operation and maintenance requirements for all stormwater management
facilities, including responsible party or parties.
(h)
The locations of septic tank infiltration areas and wells when
infiltration methods such as cisterns, seepage beds or trenches, infiltration
basins or porous pavement are used. Also, soil test data and test
locations to substantiate infiltration rates used in the drainage
calculations.
(i)
Plans and details of all erosion and sediment control measures,
temporary as well as permanent, including all calculations, assumptions,
and criteria used in designing the controls, and a schedule for their
implementation.
(j)
An encroachment map which illustrates:
2)
A preliminary grading plan which illustrates all disturbance
of the identified natural feature areas and the amount of each natural
feature disturbed indicated and illustrated on the encroachment map.
(k)
Rights-of-way and/or easements proposed to be created for all
drainage purposes, utilities or other reasons. Easements shall be
provided for all stormwater management facilities on private property
with access to public right-of-way and sufficient clearance to perform
all maintenance requirements.
C. Description of an ownership and maintenance program, in a recordable
form, that clearly sets forth the ownership and maintenance responsibility
for all temporary and permanent stormwater management facilities,
including the following:
(1)
Description of the method and extent of the maintenance requirements.
(2)
When maintained by a private entity, identification of a responsible
individual, corporation, association or other entity for ownership
and maintenance. Deed covenants and restrictions must be submitted
to provide for maintenance by this entity.
(3)
When maintained by a private entity, a copy of the legally binding
document which provides that Warminster Township shall have the right
to:
(a)
Inspect the facilities at any time.
(b)
Require the private entity to take corrective measures and assign
the private entity reasonable time periods for any necessary action.
(c)
Authorize maintenance to be done and lien the cost of the work
against the properties of the private entity responsible for maintenance.
(4)
Where the stormwater management plan proposes that Warminster
Township own or maintain the facilities, a description of the methods,
procedures, and the extent to which any facilities shall be turned
over to Warminster Township.
D. Financial security for the completion of stormwater management facilities as set forth in §
26-453 of this Part
4.
E. Maintenance guarantee, as set forth in §
26-453 of this Part
4.
F. When a stormwater management plan is submitted in sections, a generalized
stormwater management plan for the entire project site shall be submitted
in addition to the detailed stormwater management plan for the proposed
section. This generalized plan shall demonstrate how the stormwater
of the proposed section will relate to the entire development. If
temporary facilities are required for construction of a section, such
facilities shall be included in the submitted stormwater management
plan.
G. The stormwater control and BMP operations and maintenance plan for
the project site shall establish responsibilities for the continuing
operation and maintenance of all permanent stormwater controls and
BMPs, as follows:
(1)
If a plan includes structures or lots which are to be separately
owned and in which streets, sewers, and other public improvements
are to be dedicated to the municipality, stormwater controls and BMPs
may also be dedicated to and maintained by the municipality.
(2)
If a plan includes operations and maintenance by a single ownership,
or if sewers and other public improvements are to be privately owned
and maintained, then the operation and maintenance of stormwater controls
and BMPs shall be the responsibility of the owner or private management
entity.
H. The municipality shall make the final determination on the continuing
operations and maintenance responsibilities. The municipality reserves
the right to accept or reject the operations and maintenance responsibility
for any or all of the stormwater controls and BMPs.
[Ord. 691, 9/10/2009]
A modification to a submitted stormwater management plan for a proposed development site which involves a change in control methods or techniques, or which involves the relocation or redesign of control measures, or which is necessary because soil or other conditions are not as stated on the stormwater management plan (as determined by the Township Engineer) shall require a resubmission of the modified stormwater management plan consistent with §
26-433 subject to review per §
26-434 of this Part
4. Minor design changes may be permitted as authorized by the Board of Supervisors and advised by the Township Engineer without submission consistent with §
26-433 and §
26-434 of this Part
4. It shall be unlawful to alter or remove any permanent stormwater control and BMP required by an approved stormwater control and BMP operations and maintenance plan, or to allow the property to remain in a condition which does not conform to an approved stormwater control and BMP operations and maintenance plan.
[Ord. 691, 9/10/2009; as amended by Ord. No. 769, 9/8/2022]
1. The applicant shall sign an operations and maintenance agreement
with the municipality covering all stormwater controls and BMPs that
are to be privately owned. The maintenance agreement shall be transferred
with transfer of ownership. The agreement shall be substantially the
same as the agreement in Appendix E. Facilities, areas, or structures used as SWM BMPs shall
be enumerated as permanent real estate appurtenances and recorded
as deed restrictions or conservation easements that run with the land.
The O&M plan and O&M agreement shall be recorded as a restrictive
deed covenant that runs with the land.
2. Other items may be included in the agreement where determined necessary
to guarantee the satisfactory operation and maintenance of all permanent
stormwater controls and BMPs. The agreement shall be subject to the
review and approval of the municipality.
3. The owner
is responsible for operation and maintenance of the SWM BMPs. If the
owner fails to adhere to the O&M agreement, the municipality may
perform the services required and charge the owner appropriate fees.
Nonpayment of fees may result in a lien against the property.
[Added by Ord. No. 769, 9/8/2022]
A disapproved SWM site plan may be resubmitted, with the revisions
addressing the Township's concerns, to the Township in accordance
with this Part 4. The applicable review fee must accompany a resubmission
of a disapproved SWM site plan.