[Ord. No. 6-2018, 10/23/2018]
1. 
For all regulated activities, unless specifically exempted in § 26-302:
A. 
Preparation and implementation of an approved SWM site plan is required.
B. 
No regulated activities shall commence until South Hanover Township issues written approval of an SWM site plan, which demonstrates compliance with the requirements of this chapter.
C. 
The SWM site plan shall demonstrate that adequate capacity will be provided to meet the volume and rate control requirements as described under §§ 26-303 and 26-304 of this chapter.
D. 
The SWM site plan approved by South Hanover 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.
3. 
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, and meet all requirements under the Storm Water Management Act and any more-stringent requirements as determined by South Hanover Township.
4. 
South Hanover 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.
5. 
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 wherever 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.
6. 
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 developed 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.
7. 
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.
A. 
The applicant must provide an executed easement for newly concentrated flow across adjacent properties.
8. 
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.
9. 
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 may 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.
10. 
When it can be shown that, due to topographic conditions, natural drainageways on the site cannot 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.
11. 
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 permit 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.
12. 
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.
13. 
Any stormwater management facilities regulated by this chapter that will be located on, or discharged onto, state highway rights-of-way shall be subject to approval by the Pennsylvania Department of Transportation (PennDOT).
14. 
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.
15. 
Minimization of impervious surfaces and infiltration of runoff through seepage beds, infiltration trenches, etc., is encouraged, where soil conditions and geology permit, to reduce the size or eliminate the need for detention facilities.
16. 
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.
17. 
The design of facilities over karst shall include an evaluation and implementation of measures to minimize adverse effects.
18. 
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 South Hanover Township shall permit it on a case-by-case basis.
[Ord. No. 6-2018, 10/23/2018]
1. 
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.
2. 
South Hanover Township, at its discretion, may require an applicant to demonstrate that the following BMPs are being utilized to the maximum extent practicable to receive consideration for the exemptions:
A. 
Limit disturbance of floodplains, wetlands, natural slopes over 30%, 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. 
South Hanover Township, at its discretion, may require an applicant to 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.
4. 
An applicant proposing regulated activities, after demonstrating compliance with §§ 26-302, Subsections 1 and 2 may be exempted from the requirements of this chapter, according to Table 1 below and the following conditions. If the applicant requests an exemption and meets all of the conditions below, the requirements of § 26-302, Subsection 3 are assumed to be met.
[Amended by Ord. No. 6-2020, 7/14/2020]
A. 
Minimum separation.
(1) 
New impervious cover must be separated from the features listed in Subsection 4A(2) below by the minimum separation distances listed in Table 1.
(2) 
Minimum separation distance is the shortest distance from the edge of the proposed new impervious cover, or roof drain discharge point, in the flow direction of runoff, to any of the following:
(a) 
Perennial or intermittent streams or watercourses.
(b) 
Swales or ditches.
(c) 
Wetlands.
(d) 
Lakes, ponds and other surface water bodies.
(e) 
Storm sewer or combined sewer systems.
(f) 
Public roads.
(g) 
Property lines.
(h) 
Cropland, pasture land, manure storage areas and other agricultural land unless the area meets the requirements of Subsection 4D(2) below.
(i) 
Other features deemed relevant by the Township Board of Supervisors.
B. 
Multiple impervious areas.
(1) 
If the proposed new impervious area receives runoff from an existing contiguous impervious area or contributes runoff to an existing contiguous impervious area, the total impervious area to be considered for this exemption shall be the new impervious area only.
(2) 
If the existing and proposed new impervious areas are not contiguous, the total impervious area to be considered for this exemption shall be the new impervious area only. In this case, the total separation area may include the distance between the two impervious areas.
(3) 
Separation from the features listed in Subsection 4A(2) shall be determined from the edge, or roof drain discharge, of either the existing or proposed new impervious area, whichever is most downslope.
(4) 
The Township reserves the right to consider existing conditions and runoff issues in determining the needed separation area under this section.
Table 1 - Minimum Separation Distances
New Impervious Area In Square Feet
Minimum Separation Distance
Minimum Separation Distance
No Roof Drain
Roof Drain
0-250
25
40
251-500
50
75
501-1,000
75
110
1,001-1,500
100
150
1,501-2,000
125
190
2,001-2,500
150
225
2,501-3,000
175
260
3,001-4,000
200
300
4,001-5,000
225
340
Where the Township believes that the conditions of the area receiving runoff (slope, soil erosiveness, etc.) from the new impervious area may be an issue, the Township may request additional separation distance.
C. 
Discharge.
(1) 
With the exception of roof drains, runoff from the proposed new impervious cover may not be concentrated. Roof drains:
(a) 
Must discharge a stabilized separation area meeting the criteria in Table 1 and Subsection 4D.
(b) 
May not discharge to concentrated flow areas.
(2) 
Separation shall be determined from the roof drain discharge point, unless the discharge is to an impervious area. In this case, the separation shall be determined from the downslope edge of the impervious area.
D. 
Separation area.
(1) 
The area separating the proposed new impervious discharge from any features such as those listed in Subsection 4A(2) must at all times meet the following criteria:
(a) 
Be maintained in stable vegetative cover.
(b) 
Eroded areas in the separation area must be immediately repaired.
(c) 
No new impervious cover may be installed in the separation areas unless the requirements of this ordinance are met.
(d) 
Runoff in the separation area must be maintained as unconcentrated flow.
(2) 
The separation area may contain cropland, pasture land, manure storage areas and other agricultural land provided the land is in compliance with Title 25 Chapter 102.4.a (relating to erosion and sediment pollution control on agricultural land) and Title 25 Chapter 91.36.a (relating to pollution control at agricultural operations) of the Pennsylvania Code.
E. 
An applicant for an exemption that cannot meet the criteria above may qualify for reduced requirements based on the following:
(1) 
The applicant must demonstrate compliance with Subsections 1, 2, and 3 above.
(2) 
Reduced requirements will be according to the following Table 2:
Table 2 - Reduced Stormwater Management Requirements
New Impervious Area* in Square Feet Since the Date of Adoption of this Section
Applicant Must Submit to the Township
0 - 1,000
1,001 - 5,000
Volume controls and SWM site plan and report
>5,000
Rate controls, volume controls, SWM site plan and report and record drawings
*
Gravel in the existing condition shall be considered pervious and proposed gravel shall be considered impervious.
F. 
Requirement for additional stormwater management controls.
(1) 
The Township Board of Supervisors reserves the right to require additional stormwater management controls if an exempted project is determined to be causing adverse impacts of any kind.
G. 
Obligation to meet other requirements.
(1) 
Nothing in this section shall relieve the applicant of any responsibility under other regulations such as, but not limited to, Township ordinances or codes and state and federal regulations related to stormwater management, NPDES permitting requirements for erosion and sediment pollution control and post-construction stormwater management, stream and wetland encroachment or floodplain management.
H. 
Township decision.
(1) 
All requests for exemptions or modifications shall be at the discretion of the Township Board of Supervisors. Demonstration that a proposed project meets exemption or modification requirements does not necessarily obligate the Township Board of Supervisors to grant the request for exemption or modification.
(2) 
The Township Board of Supervisors may consider any and all relevant factors such as, but not limited to, runoff concentration, slope, soil characteristics, existed problems, adjacent properties, sensitive environmental features and recommendations from other Township entities such as planning commissions, Township engineers and solicitors in determining whether or not to grant any request for exemption or modification.
5. 
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. South Hanover Township may accept alternative stormwater management controls, provided that:
A. 
The applicant, in consultation with South Hanover 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 South Hanover 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, § 26-301, Subsection 4, and § 26-302, Subsections 1, 2 and 3.
6. 
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. It should be noted that temporary roadways are not exempt.
7. 
Activities that increase the impervious coverage, but the increase is accounted for and managed by a stormwater management best management practice designed and installed under an previously approved subdivision or land development plan, are exempt from the requirements of this chapter.
8. 
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.
9. 
High tunnels are exempt from the requirements of this chapter, provided that the high tunnel or its flooring does not result in an impervious area exceeding 25% of all structures located on the owner's total contiguous land area and the high tunnel meets one of the following:
A. 
The high tunnel is located at least 100 feet from any perennial stream or watercourse, public road or neighboring property line.
B. 
The high tunnel is located at least 35 feet from any perennial stream or watercourse, public road or neighboring property line and located on land with a slope not greater than 7%.
C. 
The high tunnel is supported with a buffer or diversion system that does not directly drain into a stream or other watercourse by managing stormwater runoff in a manner consistent with requirements of this chapter.
10. 
Linear roadway improvement projects that create additional impervious area are not exempt from the requirements of this chapter. However, alternative stormwater management strategies may be applied at the joint approval of South Hanover 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 of the applicant to meet the enforcement of the stormwater management standards in this chapter. All strategies must be consistent with PADEP's regulations, including NPDES requirements.
11. 
South Hanover Township may, after an applicant has demonstrated compliance with § 26-302, 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 because 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 chapter 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.
[Ord. No. 6-2018, 10/23/2018]
1. 
The low-impact development practices provided in the BMP Manual and in Appendix B of this chapter[1] shall be utilized for all regulated activities to the maximum extent practicable.
[1]
Editor's Note: Appendix B 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 sized regulated activity. This method requires detailed modeling based on site conditions.
(1) 
Do not increase the post-development total runoff volume when compared to the predevelopment total runoff volume for the two-year/twenty-four-hour storm event.
(2) 
For hydrologic modeling purposes:
(a) 
Existing nonforested pervious areas must be considered meadow (good condition) for predevelopment hydrologic calculations.
(b) 
20% of existing impervious area, when present on the proposed project site, and contained within the new proposed limit of disturbance, shall be considered meadow (good condition) for predevelopment hydrologic calculations for redevelopment.
B. 
The Simplified Method (CG-2 in the BMP Manual) 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, evaporation, transpiration, and infiltration.
(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.
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 for all proposed infiltration facilities. Infiltration tests shall be conducted in accordance with the BMP Manual. Acceptable soil will have an infiltration rate of at least 0.1 inch per hour and not more than 10 inches per hour (after application of the appropriate safety factor from the BMP Manual). The stabilized infiltration rate is to be determined in the same location and within the same soil horizon as the bottom of the infiltration facility. South Hanover Township shall be notified 24 hours prior to infiltration tests being conducted so as to provide an opportunity for South Hanover Township to witness the tests.
[Ord. No. 6-2018, 10/23/2018]
1. 
For all lands contained within South Hanover Township, the post-development peak discharge rates shall not exceed the predevelopment peak discharge rates for the one-, two-, ten-, twenty-five-, fifty-, and 100-year storms.
2. 
Lands contained within Dauphin County that have 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-, fifty-, and 100-year storms.
B. 
For the two-, ten-, and twenty-five-year storms, the post-development peak discharge rates shall be in accordance with the approved release rate map for the individual watershed.
[Ord. No. 8-2022, 11/22/2022]
1. 
In order to protect and improve water quality, a riparian buffer easement shall be created and recorded as part of any subdivision or land development that encompasses a riparian buffer.
2. 
Except as otherwise required, the riparian buffer easement shall be measured to be a minimum of 50 feet from the top of the streambanks (on each side).
3. 
Minimum management requirements for riparian buffers:
A. 
Existing native vegetation shall be protected and maintained within the riparian buffer easement and in accordance with the requirements set forth in Subsection 5, below.
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 the municipality and shall be recorded in the Dauphin County Recorder of Deeds Office, so that it shall run with the land and shall limit the use of the property located therein. The easement shall allow for the continued private ownership and shall count toward the minimum lot area as required by zoning, unless otherwise specified in the municipal Zoning Ordinance.[1]
[1]
Editor's Note: See Ch. 27, Zoning.
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 and in accordance with the riparian forest buffer management plan.
A. 
The riparian forest buffer management plan shall be available at the Township Office and on the Township website.
B. 
The Township of South Hanover may, by resolution of the Board of Supervisors, amend the riparian forest buffer management plan from time to time.
6. 
The following conditions shall apply when public and/or private recreation trails are permitted within riparian buffers:
A. 
Trails shall be for nonmotorized 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 under 25 Pa. Code Chapter 73.