[Ord. No. 24-05, 9/12/2024]
1. 
For all regulated activities, unless specifically exempted in § 19-302:
A. 
Preparation, submission, and implementation of an approved SWM Site Plan and SWM Report is required.
B. 
No regulated activities shall commence until Susquehanna Township issues written approval of a SWM Permit, which demonstrates compliance with the requirements of this Chapter.
C. 
The SWM Site Plan and Permit approved by Susquehanna Township, shall be on site throughout the duration of the regulated activities.
2. 
For all regulated earth disturbance activities, erosion and sediment control BMPs shall be designed, implemented, operated, and maintained during the regulated earth disturbance activities (e.g., during construction) to meet the purposes and requirements of this Chapter and to meet all requirements under Title 25 of the Pennsylvania Code (including, but not limited to, Chapter 102, Erosion and Sediment Control) and the Clean Streams Law. Various BMPs and their design standards are listed in the Erosion and Sediment Pollution Control Program Manual (E&S Manual), No. 363-2134-008 (April 15, 2000), as amended and updated. No earth disturbance activities within the Township associated with any regulated activities shall commence until the requirements of this Chapter are met.
3. 
An applicant proposing regulated activities shall implement the appropriate requirements of this chapter according to the following table:
SWM Permit
Altered or Developed Land
(Square Footage)
Earth Disturbance
(Square Footage)
New Impervious Area Since the Date of Adoption of this Chapter
(Square Footage)
Requirements
No Permit Required
0-999
0-4,999
0-999
—
Minor SWM Permit
1,000-4,999
5,000-43,559
1,000-4,999
Volume Controls and SWM Site Plan and Report
Major SWM Permit
>5,000
>43,560
>5,000
Rate Controls, Volume Controls, SWM Site Plan and Report, and Record Drawings
4. 
For all regulated activities, stormwater BMPs shall be designed, installed, implemented, operated, and maintained to meet the purposes and requirements of this Chapter and to meet all requirements under Title 25 of the Pennsylvania Code and the Clean Streams Law, conform to the State Water Quality Requirements, meet all requirements under the Storm Water Management Act and any more stringent requirements as determined by Susquehanna Township.
5. 
Susquehanna Township may, after consultation with PADEP and/or DCCD, approve measures for meeting the State Water Quality Requirements other than those in this Chapter, provided that they meet the minimum requirements of, and do not conflict with, state law, including, but not limited to, the Clean Streams Law.
6. 
All regulated activities shall include, to the maximum extent practicable, measures to:
A. 
Protect health, safety, and property.
B. 
Meet the water quality goals of this Chapter by implementing measures to:
(1) 
Minimize disturbance to floodplains, wetlands, natural slopes, existing native vegetation and woodlands.
(2) 
Create, maintain, or extend riparian buffers and protect existing forested buffers.
(3) 
Provide trees and woodlands adjacent to impervious areas whenever feasible.
(4) 
Minimize the creation of impervious surfaces and the degradation of waters of the Commonwealth and promote groundwater recharge.
(5) 
Protect natural systems and processes (drainageways, vegetation, soils, and sensitive areas) and maintain, as much as possible, the natural hydrologic regime.
(6) 
Incorporate natural site elements (wetlands, stream corridors, mature forests) as design elements.
(7) 
Avoid erosive flow conditions in natural flow pathways.
(8) 
Minimize soil disturbance and soil compaction.
(9) 
Minimize thermal impacts to waters of the Commonwealth.
(10) 
Disconnect impervious surfaces by directing runoff to pervious areas where possible and decentralize and manage stormwater at its source.
C. 
Applicants are encouraged to incorporate the techniques for low impact development practices described in the Pennsylvania Stormwater Best Management Practices Manual (BMP Manual) to reduce the costs of complying with the requirements of this Chapter and the state water quality requirements. If methods other than green infrastructure and LID methods are proposed to achieve the volume and rate controls required under this Chapter, the SWM Site Plan must include a detailed justification demonstrating that the use of LID and green infrastructure is not practicable.
(1) 
However, green infrastructure and LID methods must be used to the maximum extent practicable when developing a SWM Site Plan for a project.
(2) 
If green infrastructure and LID methods are not feasible then a waiver request for traditional stormwater management practices must be submitted to Susquehanna Township. The following conditions may be used to determine if the project site is not feasible for green infrastructure and LID methods:
(a) 
Poor soil quality.
(b) 
Hydrologic soil classification of C or worse.
(c) 
Failed infiltration tests.
(d) 
Erroneous grade changes, such as excessive cut or fill or lack of suitable areas.
(e) 
Proposed project results in lot coverage exceeding 45%.
(3) 
All applicable studies and test results listed above shall be presented with waiver for proof of exemption.
7. 
Impervious Areas.
A. 
The measurement of impervious areas shall include all of the impervious areas in the total proposed development, even if development is to take place in stages.
B. 
For development taking place in stages, the entire development plan must be used in determining conformance with this Chapter.
C. 
For projects that add impervious area to a development parcel, the new impervious area is subject to the requirements of this Chapter, and any existing impervious area that is within the new proposed limit of disturbance is also subject to the requirements of this Chapter.
8. 
If diffused flow is proposed to be concentrated and discharged onto adjacent property, the applicant must document that adequate downstream conveyance facilities exist to safely transport the concentrated discharge, or otherwise prove that no erosion, sedimentation, flooding, or other harm will result from the concentrated discharge. Such stormwater flows shall be subject to the requirements of this Chapter and any applicable local municipal codes. If the diffused flow is to be concentrated and discharged onto adjacent property, it shall be done so in accordance with PADEP guidance documentation.
A. 
The applicant must provide an executed easement for newly concentrated flow across adjacent properties.
9. 
Stormwater drainage systems shall be provided in order to permit unimpeded flow along natural watercourses, except as modified by stormwater management facilities or open channels consistent with this Chapter.
10. 
Where watercourses traverse a development site, drainage easements (with a minimum width of 20 feet) shall be provided conforming to the line of such watercourses. The terms of the easement shall prohibit excavation, the placing of fill or structures, and any alterations that my adversely affect the flow of stormwater within any portion of the easement. Also, maintenance, including mowing of vegetation within the easement may be required, except as approved by the appropriate governing authority.
11. 
When it can be shown that, due to topographic conditions, natural drainageways on the site cannot be adequately provide for drainage, open channels, may be constructed conforming substantially to the line and grade of such natural drainageways. Work within natural drainageways shall be subject to approval by PADEP under regulations at 25 Pa. Code Chapter 105 through the joint permit application process or, where deemed appropriate by PADEP, through the general permit process.
12. 
Any stormwater management facilities or any facilities that constitute water obstructions (e.g., culverts, bridges, outfalls, or stream enclosures, etc.) that are regulated by this Chapter, that will be located in or adjacent to waters of the Commonwealth (including wetlands), shall be subject to approval by PADEP under regulations at 25 Pa. Code Chapter 105 through the joint permitting application process or, where deemed appropriate by PADEP, the general permit process. When there is a question whether wetlands may be involved, it is the responsibility of the applicant or his agent to show that the land in question cannot be classified as wetlands; otherwise, approval to work in the area must be obtained from PADEP.
13. 
Should any stormwater management facility require a dam safety permit under PADEP Chapter 105, the facility shall be designed in accordance with Chapter 105 and meet the regulations of Chapter 105 concerning dam safety which may be required to pass storms larger than the 100-year event.
14. 
Any stormwater management facilities regulated by this Chapter that will be located on or discharge onto state highway rights-of-way shall be subject to approval by PennDOT.
15. 
When stormwater management facilities are proposed within 1,000 feet of a downstream municipality, the stormwater analysis shall be submitted to the downstream municipality's engineer for review and comment.
16. 
Minimization of impervious surfaces and infiltration of runoff through seepage beds, infiltration trenches, etc., are encouraged, where soil conditions and geology permit, to reduce the size or eliminate the need for detention facilities.
17. 
Infiltration BMPs should be dispersed throughout the site, made as shallow as practicable, and located to maximize use of natural on-site infiltration features while still meeting the other requirements of this Chapter.
18. 
The design of facilities over karst shall include an evaluation and implementation of measures to minimize adverse effects.
19. 
Roof drains shall not be connected to streets, sanitary or storm sewers, or roadside ditches in order to promote overland flow and infiltration/percolation of stormwater where it is advantageous to do so. When it is more advantageous to connect directly to streets or storm sewers, then Susquehanna Township shall permit it on a case-by-case basis.
20. 
Normally dry, open top, storage facilities should completely drain both the volume control and rate control capacities over a period of time not less than 24 hours and not more than 72 hours from the end of the design storm.
21. 
The design storm volumes to be used in the analysis of peak rate of discharge should be obtained from the latest version of the Precipitation-Frequency Atlas of the United States, National Oceanic and Atmospheric Administration (NOAA), National Weather Service, Hydrometeorological Design Studies Center, Silver Spring, Maryland. (NOAA's Atlas 14 can be accessed at: http://hdsc.nws.noaa.gov/hdsc/pdfs/)
22. 
For all regulated activities, SWM BMPs shall be designed, implemented, operated, and maintained to meet the purposes and requirements of this Chapter, and to meet all requirements under Title 25 of the Pennsylvania Code, the Clean Streams Law, and the Storm Water Management Act.
[Ord. No. 24-05, 9/12/2024]
1. 
Regulated activities that result in any one or more of (1) the alteration or development of less than 1,000 square feet of land in a manner that may affect stormwater runoff; (2) earth disturbances of less than 5,000 square feet; or (3) the cumulative increase of impervious area less than 1,000 square feet since the first regulated instance under this Chapter or the preceding versions of the Susquehanna Township stormwater regulations, regardless of whether a permit was properly applied for and received, are exempt from the requirements in Part 6 of this Chapter.
2. 
Under no circumstance shall the applicant be exempt from implementing such measures as necessary to:
A. 
Meet state water quality standards and requirements.
B. 
Protect health, safety, and property.
C. 
Meet special requirements for high quality (HQ) and exceptional value (EV) watersheds.
3. 
Forest management and timber operations are exempt from rate and volume control requirements and SWM Site Plan preparation requirement of this Chapter, provided the activities are performed according to the requirements of 25 Pa. Code Chapter 102.
4. 
Agricultural activities are exempt from the requirements of this Chapter, provided the activities are performed according to the requirements of 25 Pa. Code Chapter 102.
5. 
Construction of sidewalks and curbing within public rights-of-way.
6. 
Linear roadway improvement projects that create additional impervious area are not exempt from the requirements of this Chapter. However, the alternative stormwater management strategies may be applied at the joint approval of Susquehanna Township and the Dauphin County Conservation District (if an NPDES permit is required) when site limitations (such as limited right-of-way) and constraints (as shown and provided by the applicant), preclude the ability to meet the enforcement of the stormwater management standards in this Chapter. All strategies must be consistent with PADEP's regulations, including NPDES requirements.
7. 
Susquehanna Township may, after an applicant has demonstrated compliance with § 19-302, Subsections 1, 2 and 3, grant a modification of the requirements of one or more provisions of this Chapter if the literal enforcement will exact undue hardship of peculiar conditions pertaining to the land in question, provided that such modification will not be contrary to the public interest and that the purpose and intent of the Ordinance is observed.
A. 
All requests for a modification shall be in writing and shall state in full the grounds and facts of unreasonableness or hardship on which the request is based, the provision or provisions of the Ordinance involved, and the minimum modification necessary.
8. 
Not eligible for exemption: additions, modifications, or alterations to sites, structures, pipes, swales or other conveyance systems, projects, plans, or any other items that previously required stormwater management, whether in part or in whole (for example: adding a 500 square foot patio onto a home built as part of a larger subdivision and land development plan that required stormwater management would not be an exempt regulated activity).
9. 
Susquehanna Township may deny or revoke any exemption pursuant to this Chapter at any time for any project that the Township determines poses a threat to public health, safety, property or the environment.
[Ord. No. 24-05, 9/12/2024]
1. 
The purpose of this Section is to ensure consistency of stormwater management planning between local ordinances and NPDES permitting (when required) and to ensure that the applicant has a single and clear set of stormwater management standards to which the applicant is subject. Susquehanna Township may accept alternative stormwater management controls, provided that:
A. 
The applicant, in consultation with Susquehanna Township, PADEP, and/or DCCD, states that meeting the requirements of the volume controls or rate controls of this Chapter is not possible or creates an undue hardship.
B. 
The alternative stormwater management controls, proposed by the applicant, are documented to be acceptable to Susquehanna Township, PADEP, and/or DCCD for NPDES requirements pertaining to post-construction stormwater management requirements.
C. 
The alternative stormwater management controls are in compliance with all other sections of this Chapter, including, but not limited to, § 19-301, Subsection 4, § 19-302, Subsections 1 and 3.
2. 
The applicant must demonstrate that the following BMPs are being utilized to the maximum extent practicable to receive consideration for the exemptions:
A. 
Design around and limit disturbance of floodplains, wetlands, natural slopes over 15%, existing native vegetation, and other sensitive and special value features.
B. 
Maintain riparian and forested buffers.
C. 
Limit grading and maintain nonerosive flow conditions in natural flow paths.
D. 
Maintain existing tree canopies near impervious areas.
E. 
Minimize soil disturbance and reclaim disturbed areas with topsoil and vegetation.
F. 
Direct runoff to pervious areas.
3. 
The applicant must demonstrate that the proposed development/additional impervious area will not adversely impact the following:
A. 
Capacities of existing drainageways and storm sewer systems.
B. 
Velocities and erosion.
C. 
Quality of runoff if direct discharge is proposed.
D. 
Existing known problem areas.
E. 
Safe conveyance of the additional runoff.
F. 
Downstream property owners.
1. 
The green infrastructure and low impact development practices provided in the BMP Manual and in Appendix B[1] of this Chapter shall be utilized for all regulated activities to the maximum extent practicable.
[1]
Editor's Note: Said appendix is included as an attachment to this chapter.
2. 
Stormwater runoff volume controls shall be implemented using the design storm method or the simplified method. For regulated activities equal to or less than one acre, this Chapter establishes no preference for either method; therefore, the applicant may select either method on the basis of economic considerations, the intrinsic limitations on applicability of the analytical procedures associated with each methodology, and other factors.
A. 
The Design Storm Method (CG-1 in the BMP Manual) is applicable to any size of regulated activity. This method requires detailed modeling based on site conditions.
(1) 
Do not increase the post-development total runoff volume for all storms equal to or less than the two-year, 24-hour duration precipitation.
(2) 
For hydrologic modeling purposes:
(a) 
Existing (predevelopment) non-forested pervious areas must be considered meadow in good condition.
(b) 
20% of existing impervious area, when present on the proposed project site, and contained within the new proposed limited of disturbance, shall be considered meadow (good condition) for predevelopment hydrologic calculations for redevelopment.
B. 
The simplified method (CG-2 in the BMP Manual) provided below is independent of site conditions and should be used if the design storm method is not followed. This method is not applicable to regulated activities greater than one acre. For new impervious surfaces:
(1) 
Stormwater facilities shall capture at least the first two inches of runoff from all new impervious surfaces.
(2) 
At least the first one inch of runoff from new impervious surfaces shall be permanently removed from the runoff flow, i.e., it shall not be released into surface waters of the Commonwealth. Removal options include reuse, evapotranspiration, and infiltration. The Managed Release Concept may be used to manage volume with approval from Susquehanna Township and its assignees, if it is demonstrated the volume cannot be permanently removed through the preceding options.
(3) 
Wherever possible, infiltration facilities should be designed to accommodate infiltration of the entire permanently removed runoff; however, in all cases at least the first 0.5 inch of the permanently removed runoff should be infiltrated. Managed Release Concept may be used as alternative upon approval from Susquehanna Township and its assignees.
(4) 
This method is exempt from the requirements of § 19-304, Rate Controls.
3. 
All applicable worksheets from Chapter 8 of the BMP Manual must be used when establishing volume controls.
4. 
Actual field infiltration tests at the location of the proposed elevation of the stormwater BMPs are required when 5,000 square feet or greater of new impervious surface is added. Infiltration test shall be conducted in accordance with the BMP Manual. Susquehanna Township shall be notified 24 hours prior to infiltration testing as to provide an opportunity for Susquehanna Township to witness the tests.
5. 
Actual field infiltration tests shall be required when infiltration facilities are proposed within areas of soils having a Hydraulic Soil Group classification of C or worse. Based on site conditions and or projects occurring in close proximity (two-mile radius) to the proposed project location where failures in infiltration facilities have occurred, preliminary field infiltration results shall be provided to Susquehanna Township in conjunction with their SWM Site Plan and Report.
1. 
Lands contained within Susquehanna Township that have not had release rates established under an approved Act 167 Stormwater Management Plan:
A. 
Post-development discharge rates shall not exceed the predevelopment discharge rates for the one-, two-, 10-, 25-, 50-, and 100-year storms.
2. 
Lands contained within Susquehanna Township that have had release rates established under an approved watershed-wide Act 167 Stormwater Management Plan [Paxton Creek, Spring Creek (West), and Fishing Creek]:
A. 
Post-development discharge rates shall not exceed the predevelopment discharge for the one-, 50-, and 100-year storms.
B. 
For the two-, 10-, and 25-year storms, the post-development peak discharge rates shall be in accordance with the approved release rate map for the individual watershed.
3. 
For lands contained within a Paxton Creek Watershed Provisional No Detention District:
A. 
These watershed areas may discharge post-development peak runoff without detention facilities. However, the applicant must prove that the "local" runoff conveyance facility which transports runoff from the site to the main channel has adequate capacity to safely transport unattenuated increased peak flows for a 25-year storm in accordance with § 19-306. If there is inadequate capacity, the applicant shall either use 100% release rate control or provide increased capacity of downstream drainage facilities to convey increase peak flows consistent with § 19-306. When determining if adequate capacity exists in the local watershed drainage network, the applicant must assume that the entire local watershed is developed per current zoning and that all new development will use the least restrictive runoff controls specified by this Chapter.
4. 
Off-site areas that drain through a proposed development site are not subject to release rate criteria when determining allowable peak runoff rate; however, on-site drainage facilities shall be designed to safely convey off-site flows through the development site.
5. 
For proposed development site, which is located within two or more release rate districts, the maximum runoff discharge at any point shall be equal to the release rate for the district in which the discharge point is located. In the event that a portion of the site is located within a provisional no detention area, no runoff from portions of the site located in areas subject to release rate controls may be drained to or through the provisional no detention area.
Any downstream hydraulic capacity analysis conducted in accordance with this Chapter shall use the following criteria for determining adequacy for accepting increased peak flow rates:
1. 
Natural or man-made channels or swales must be able to convey the increased runoff associated with a 25-year return period event within their banks at velocities consistent with protection of the channels from erosion. Acceptable velocities shall be based upon criteria included in the PADEP Erosion and Sediment Pollution Control Program Manual.
2. 
Natural or man-made channels or swales must be able to convey the increased 25-year return period runoff without creating any hazard to persons or property.
3. 
Culverts, bridges, storm sewers, or any other facilities which must pass or convey flows from the tributary area must be designed in accordance with PADEP Chapter 105 regulations (if applicable) and, at a minimum, pass the increased 25-year return period runoff, except for facilities located within a designed floodplain area which must, at a minimum, conform to FEMA and local floodplain ordinance requirements.
1. 
In order to protect and improve water quality, a riparian buffer easement shall be created and recorded as part of any subdivision, land development, or development of an individual lot, that encompasses a riparian buffer.
2. 
Except as required by Chapter 102, the riparian buffer easement shall be measured to be the greater of the limit of the 100-year floodplain or a minimum of 35 feet from the top of the streambank (on each side).
3. 
Minimum Management Requirements for Riparian Buffers.
A. 
Existing native vegetation shall be protected and maintained within the riparian buffer easement.
B. 
Whenever practicable, invasive vegetation shall be actively removed and the riparian buffer easement shall be planted with native trees, shrubs, and other vegetation to create a diverse native plant community appropriate to the intended ecological context of the site.
4. 
The riparian buffer easement shall be enforceable by Susquehanna Township and shall be recorded in the Dauphin County Recorder of Deeds Office, so that it shall run with the land shall limit the use of the property located therein.
5. 
Any permitted use within the riparian buffer easement shall be conducted in a manner that will maintain the extent of the existing 100-year floodplain, improve or maintain the stream stability, and preserve and protect the ecological function of the floodplain.
6. 
The following conditions shall apply when public and/or private recreation trails are permitted within riparian buffers:
A. 
Trails shall be for non-motorized use only.
B. 
Trails shall be designed to have the least impact on native plant species and other sensitive environmental features.
7. 
Septic drainfields and sewage disposal systems shall not be permitted within the riparian buffer easement and shall comply with setback requirements established in 25 Pa. Code Chapter 73.