§ 123-44. Flood-prone areas; drainage.

A. 

Those areas defined as floodplains by the Floodplain Conservation District of the Township Zoning Ordinance shall be subject to the requirements and restrictions contained in Chapter 143, Zoning, and the following additional regulations which are intended to conform to the requirements of Section 1910.3d of the National Flood Insurance Program, P.L. 93-234. It is the purpose of these regulations to:

(1) 

Regulate the subdivision and development of flood-prone land areas in order to promote the general health, welfare and safety of the community.

(2) 

Require that each subdivision lot or development site in flood-prone areas be provided with a safe building site with adequate access and that public facilities which serve such sites be designed and installed to preclude flood damage at the time of initial construction.

(3) 

Protect individuals from buying lands which are unsuitable for use because of flood hazards by prohibiting the subdivision and development of unprotected flood-prone areas.

(4) 

Maintain the certification of Lower Providence Township and the eligibility of the property owners in Lower Providence Township for the benefits of the National Flood Insurance Program, P.L 93-234.

B. 

Preapplication procedures for subdivision and land developments. Prospective developers shall consult the Montgomery County Conservation District representative concerning erosion and sediment control measures, the effort of geologic conditions on the proposed subdivision and land development and the potential impact of the proposed subdivision and land development on geologic conditions.

C. 

The following requirements shall apply for all subdivision and land developments proposed in Lower Providence Township:

(1) 

Where not prohibited by this Part 1 or any other codes or ordinances, land located in flood-prone area(s) may be subdivided or developed with the provision that the developer construct all buildings and structures to preclude flood damage in accordance with this Part 1 and any other codes or ordinances regulating such development.

(2) 

The Board of Supervisors may, when it is deemed necessary for the health, comfort, safety or welfare of the present and future population of the area and necessary to the conservation of water, drainage and sanitary facilities, prohibit subdivision of any portion of the property which lies within the floodplain of any stream or drainage course.

(3) 

No subdivision or land development shall be approved if the proposed development or improvements will, individually or collectively, increase the established flood level or regulatory flood elevation (where applicable) more than one foot on the subject property or on any upstream or downstream property.

[Amended 8-10-1992 by Ord. No. 384]

(4) 

If the Board of Supervisors determines that only a portion of a proposed plan can be safely developed, it shall limit development to that part and shall require that development proceed consistent with this determination.

(5) 

When a developer does not intend to develop the plan himself and the Board of Supervisors determines that additional controls are required to ensure safe development, it may require the developer to impose appropriate deed restrictions on the land. Such deed restrictions shall be inserted in every deed and noted on the record plan.

D. 

Where any excavation or grading is proposed or where any existing trees, shrubs or other vegetative cover will be removed, the developer shall abide by the regulations in the Township's Stormwater and Erosion Control Ordinance.

Editor's Note: See Part 3, Stormwater and Erosion Control, of this chapter.

E. 

Storm drainage facilities shall be designed to convey the flow of surface waters without risk to persons or property. The drainage system shall ensure drainage at all points along streets and ensure conveyance of drainage away from buildings and on-site waste disposal sites.

F. 

The Board of Supervisors may require an underground system to accommodate frequent floods and a secondary surface system to accommodate larger, less frequent floods. Drainage plans shall be consistent with local and regional drainage plans. The facilities shall be designed to prevent the discharge of excess runoff onto adjacent properties.

G. 

Any development which creates a significant change in the characteristics of the watershed, thus increasing volume and velocity of surface water runoff, due to the decrease in retention and infiltration of stormwater, shall not be permitted until guaranties are made of improvements that will reduce the likelihood of erosion, sedimentation, inundation and water drainage from peak periods of precipitation and that provide for controlled disposal of excess surface water. Such improvements must satisfy the requirements and regulations of the Pennsylvania Department of Environmental Protection, Bureaus of Water Quality Management and Dams and Encroachments.

H. 

When approved as a conditional use, the finished elevation of proposed streets shall be no more than two feet below the regulatory flood elevation, where available. Drainage openings shall be sufficient to discharge flood flows without unduly increasing flood heights.

[Amended 8-10-1992 by Ord. No. 384]

I. 

(Reserved)

Editor's Note: Former Subsection I was deleted 8-10-1992 by Ord. No. 384.

J. 

All sanitary sewer systems located in flood-prone areas, whether public or private, shall be floodproofed up to a point 1 1/2 feet above the regulatory flood elevation, where available.

(1) 

The Board of Supervisors may prohibit installation of sewage disposal facilities requiring soil absorption systems where such systems will not function due to high groundwater, flooding or unsuitable soil characteristics. The Board of Supervisors may require that the developer note on the plan and in any deed of conveyance that on-site sewage disposal systems are prohibited in designated flood-prone areas.

(2) 

The Board of Supervisors may prescribe adequate methods for waste disposal. If a public sanitary sewer system is located within or near the proposed subdivision or land development, the Board of Supervisors shall require the developer to connect to this system, where practical, and shall prescribe the procedures to be followed by the developer in connecting to said system.

K. 

All water systems in flood-prone areas, whether public or private, shall be floodproofed to a point 1 1/2 feet above the established flood level or regulatory flood elevation, where available. If there is an existing centralized water supply system within or near the subdivision or land development, the Board of Supervisors shall require the developer to connect to this system, where practical, and shall prescribe the procedures to be followed by the developer in connecting to said system.

L. 

All other public or private utilities and facilities shall be elevated or floodproofed to a point 1 1/2 feet above the established flood level or regulatory flood elevation, where available.

M. 

The Board of Supervisors, in its consideration of any preliminary plan of subdivision and land development, shall condition its approval upon the execution of measures designed prevent accelerated soil erosion and resulting sedimentation, as required by the Pennsylvania Department of Environmental Protection. All applicable regulations and permit requirements of said Department, as stipulated in its Soil Erosion and Sedimentation Control Manual, shall be followed by all parties engaged in earthmoving activities.

N. 

All continuously flowing natural watercourses shall be maintained in their natural state, except that removal of debris and correction of severe erosion shall be required.

O. 

Intermittent watercourses often are significant elements at the headwaters of larger streams and are usually small in size. Therefore, developers should be encouraged to design and build around with respect for these drainageways, and the Board of Supervisors may allow rerouting of these drainageways only when serious considerations so warrant or when the site drainage will be improved by such proposed alignment changes.

P. 

Unless alignment is authorized in accordance with Subsection O above, intermittent watercourses shall be maintained essentially at their existing alignments and gradients, except that they may be improved by minor regrading and shall either be planted in grass or provided with erosion preventive improvements, such as riprap. Paving of such watercourses shall not be allowed nor shall piping, except under roads, driveways and walkways.

Q. 

Where a subdivision or land development lies partially or completely in a flood-prone area or where the subdivision or land development borders on a flood-prone area, the plan shall include detailed information identifying the following:

(1) 

The location and elevation of existing and proposed streets, water supply and sanitary facilities, building sites, structures, soil types and proposed floodproofing measures.

(2) 

The boundaries of the floodplain area and the base flood elevation as defined in the Floodplain Conservation District of the Lower Providence Township Zoning Ordinance.

Editor's Note: A description of the Floodplain Conservation District is contained in the Zoning Ordinance. See Ch. 143, Zoning.

R. 

Requirements and calculations. All storm sewers and culverts in flood-prone areas shall be installed in conformance with the Township's Engineering Standards and in conformance with the Township Stormwater and Erosion Control Ordinance.

Editor's Note: See , Engineering Standards, included at the end of this chapter, and Part 3, Stormwater and Erosion Control, of this chapter.

S. 

Waivers. Guidelines for relaxation from the requirements set forth in this section are as follows:

(1) 

A waiver shall not be issued within any designated regulatory floodway if any increase in flood levels during the base flood discharge would result.

(2) 

A waiver shall only be issued if there is:

(a) 

A showing of good and sufficient cause.

(b) 

A determination that failure to relax the requirements would result in exceptional hardship to the applicant.

(c) 

A determination that the relaxing of a requirement will not result in increased flood heights, additional threats to public safety or extraordinary public expense; create nuisances; cause fraud on or victimization of the public; or conflict with existing local laws or ordinances.

(3) 

A waiver shall only be issued upon a determination that the waiver is the minimum necessary, considering the flood hazard, to afford relief.

(4) 

The Township shall maintain a record of all waivers, including justification for their issuance, and report such decisions issued in its annual report submitted to the Federal Insurance Administrator.

Editor's Note: See also Ch. 86, Floodplains.