Township of Allen, PA C Stormwater Management Requirements.

§ 8-221 General Requirements.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; by Ord. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

1. All regulated activities in the Township shall be subject to the stormwater management requirements of this Part.

2. Storm drainage systems shall be provided to permit unobstructed flow in natural watercourses except as modified by stormwater detention facilities, recharge facilities, water quality facilities, pipe systems or open channels consistent with this Part.

3. The existing locations of concentrated drainage discharge onto adjacent property shall not be altered without written approval of the affected property owner(s).

4. Areas of existing diffused drainage discharge onto adjacent property shall be managed such that, at minimum, the peak diffused flow does not increase in the general direction of discharge, except as otherwise provided in this Part. If diffused flow is proposed to be concentrated and discharged onto adjacent property, the developer must document that there are adequate downstream conveyance facilities to safely transport the concentrated discharge to the point of predevelopment flow concentration, to the stream reach or otherwise prove that no harm will result from the concentrated discharge. Areas of existing diffused drainage discharge shall be subject to any applicable release rate criteria in the general direction of existing discharge whether they are proposed to be concentrated or maintained as diffused drainage areas.

5. Where a site is traversed by watercourses other than those for which a 100-year floodplain is defined by the Township, there shall be provided drainage easements conforming substantially with the line of such watercourses. The width of any easement shall be adequate to provide for unobstructed flow of storm runoff based on calculations made in conformance with § 8-224 for the 100-year return period runoff and to provide a freeboard allowance of 0.5 foot above the design water surface level. The terms of the easement shall prohibit excavation, the placing of fill or structures, and any alterations which may adversely affect the flow of stormwater within any portion of the easement. Also, periodic maintenance of the easement to ensure proper runoff conveyance shall be required. Watercourses for which the 100-year floodplain is formally defined are subject to the applicable Township floodplain regulations.

6. When it can be shown that, due to topographic conditions, natural drainage swales on the site cannot adequately provide for drainage, open channels may be constructed conforming substantially to the line and grade of such natural drainage swales. Capacities of open channels shall be calculated using the Manning Equation.

7. Post-construction BMPs shall be designed, installed, operated, and maintained to meet the requirements of the Clean Streams Law[1] and implementing regulations, including the established practices in 25 Pa. Code Chapter 102 and the specifications of this Part as to prevent accelerated erosion in watercourse channels and at all points of discharge.

[1] Editor's Note: See 35 P.S. § 691.1 et seq.

8. No earth disturbance activities associated with any regulated activities shall commence until approval by the Township of a plan which demonstrates compliance with the requirements of this Part.

9. Techniques described in Appendix F[2] (Low Impact Development) of this chapter are encouraged because they reduce the costs of complying with the requirements of this Part and the state water quality requirements.

[2] Editor's Note: Appendix F is included as an attachment to this chapter.

10. Green infrastructure practices provided in the BMP Manual shall be utilized for all regulated activities wherever possible.

11. Infiltration for stormwater management is required where soils and geology permit, consistent with the provisions of this Part and, where appropriate, the Recommendation Chart for Infiltration Stormwater Management BMPs in Carbonate Bedrock in Appendix D.[3]

[3] Editor's Note: Appendix D is included as an attachment to this chapter.

§ 8-222 Stormwater Management Districts.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

1. Mapping of Stormwater Management Districts. To implement the provisions of the Pennsylvania Department of Environmental Protection approved stormwater management plans (and plan update), the Township is hereby divided into stormwater management districts consistent with the release rate maps presented in the plan update. The boundaries of the stormwater management districts are shown on official maps which are available for inspection at the Township office. Copies of the official maps at a reduced scale are included in Appendix A[1] for general reference.

[1] Editor's Note: Appendix A is included as an attachment to this chapter.

2. Description of Stormwater Management Districts. Two types of stormwater management districts may be applicable to the Township, namely Conditional/Provisional No Detention Districts and Dual Release Rate Districts as described below.

A. Conditional/Provisional No Detention Districts. Within these districts, the capacity of the local runoff conveyance facilities (as defined in § 8-211) must be calculated to determine if adequate capacity exists. For this determination, the developer must calculate peak flows assuming that the site is developed as proposed and that the remainder of the local watershed is in the existing condition. The developer must also calculate peak flows assuming that the entire local watershed is developed per current zoning and that all new development would use the runoff controls specified by this Part. The larger of the two peak flows calculated will be used in determining if adequate capacity exists. If adequate capacity exists to safely transport runoff from the site to the main channel (as defined in § 8-211), these watershed areas may discharge post-development peak runoff without detention facilities. If the capacity calculations show that the local runoff conveyance facilities lack adequate capacity, the developer shall either use a 100% release rate control or provide increased capacity of downstream elements to convey increased peak flows consistent with § 8-223, Subsection 13. Any capacity improvements must be designed to convey runoff from development of all areas tributary to the improvement consistent with the capacity criteria specified in § 8-223, Subsection 3. By definition, a storm drainage problem area associated with the local runoff conveyance facilities indicates that adequate capacity does not exist. Sites in these districts are still required to meet all of the water quality requirements in §§ 8-227, 8-228 and 8-229.

B. Dual Release Rate Districts. Within these districts, the two-year post-development peak discharge must be controlled to 30% of the predevelopment two-year runoff peak. Further, the ten-, twenty-five-, and 100-year post-development peak runoff must be controlled to 100% of the predevelopment peak.

§ 8-223 Stormwater Management District Implementation Provisions.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; by Ord. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

1. Any stormwater management controls required by this Part and subject to single release rate criteria shall meet the applicable release rate criteria for each of the two-, ten-, twenty-five-, and 100-year return period runoff events consistent with the calculation methodology specified in § 8-224. Stormwater management controls intended to meet the dual release rate (30%/100%) criteria shall also be designed consistent with § 8-224.

2. The exact location of the stormwater management district boundaries as they apply to a given development site shall be determined by mapping the boundaries using the two-foot topographic contours provided as part of the drainage plan. The district boundaries as originally drawn coincide with topographic divides or, in certain instances, are drawn from the intersection of the watercourse and a physical feature such as the confluence with another watercourse or a potential flow obstruction (e.g., road, culvert, bridge, etc.). The physical feature is the downstream limit of the subarea and the subarea boundary is drawn from that point upslope to each topographic divide along the path perpendicular to the contour lines.

3. Any downstream capacity analysis conducted in accordance with this Part shall use the following criteria for determining adequacy for accepting increased peak flow rates:

A. Natural or man-made channels or swales must be able to convey the increased runoff associated with a two-year return period event within their banks at velocities consistent with protection of the channels from erosion.

B. Natural or man-made channels or swales must be able to convey the increased twenty-five-year return period runoff peak within their banks or otherwise not create any hazard to persons or property.

C. Culverts, bridges, storm sewers or any other facilities which must pass or convey flows from the tributary area must have sufficient capacity to pass or convey the increased flows associated with the twenty-five-year return period runoff event, except for facilities located within a designated floodplain area which must be capable of passing or conveying the 100-year return period runoff. Any facilities which constitute stream enclosures per DEP's Chapter 105 regulations shall be designed to convey the 100-year return period runoff.

4. For a proposed development site located within only one release rate category subarea, the total runoff from the site shall meet the applicable release rate criteria. For development sites with multiple directions of runoff discharge, individual drainage directions may be designed for up to a 100% release rate so long as the total runoff from the site is controlled to the applicable release rate.

5. For a proposed development site located within two or more release category subareas, the peak discharge rate from any subarea shall be the predevelopment peak discharge for that subarea multiplied by the applicable release rate. The calculated peak discharges shall apply regardless of whether the grading plan changes the drainage area by subarea. An exception to the above may be granted if discharges from multiple subareas recombine in proximity to the site. In this case, peak discharge in any direction may be a 100% release rate, provided that the overall site discharge meets the weighted average release rate.

6. For proposed development sites located partially within a release rate category area and partially within a provisional or conditional no detention area, in no event shall a significant portion of the site area subject to the release rate control be drained to the discharge point(s) located in the no detention area.

7. Within a release rate category area, for a proposed development site which has areas which drain to a closed depression(s), the design release from the site will be the lesser of a) the applicable release rate flow assuming no closed depression(s), or b) the existing peak flow actually leaving the site. In cases where b) would result in an unreasonably small design release, the design discharge of less than or equal to the release rate will be determined by the available downstream main channel calculated using § 8-223 criteria.

8. Off-site areas which drain through a proposed development site are not subject to release rate criteria when determining allowable peak runoff rates. However, on-site site drainage facilities shall be designed to safely convey off-site flows through the development site, and provide easements for this flow.

9. Where the area to be impacted by a proposed development activity differs significantly from the total development area, only the proposed impact area shall be subject to the release rate criteria.

10. Development proposals which, through groundwater recharge or other means, do not increase both the rate and volume of runoff discharged from the site are not subject to the release rate provisions of the Part.

11. No-Harm Water Quantity Option.

A. For any proposed development site not located in a Conditional/Provisional No Detention District, the developer has the option of using a less restrictive runoff control (including no detention) if the developer can prove that special circumstances exist for the proposed development site and that "no harm" would be caused by discharging at a higher runoff rate than that specified by the plan. Special circumstances are defined as any hydrologic or hydraulic aspects of the development itself not specifically considered in the development of the plan runoff control strategy. Proof of "no harm" would have to be shown from the development site through the remainder of the downstream drainage network to the confluence of the creek with the Lehigh River. Proof of "no harm" must be shown using the capacity criteria specified in § 8-223, Subsection 3, if downstream capacity analysis is a part of the "no harm" justification. Attempts to prove "no harm" based upon downstream peak flow versus capacity analysis shall be governed by the following provisions:

(1) The peak flow values to be used for downstream areas for the design return period storms (two-, ten-, twenty-five-, and 100-year) shall be the values from the calibrated PSRM model for the watershed or as calculated by an applicant using an alternate method acceptable to the Township. The flow values from the PSRM model would be supplied to the developer by the Township upon request.

(2) Any available capacity in the downstream conveyance system as documented by a developer may be used by the developer only in proportion to his development site acreage relative to the total upstream undeveloped acreage from the identified capacity (i.e., if his site is 10% of the upstream undeveloped acreage, he may use up to 10% of the documented downstream available capacity).

(3) Developer-proposed runoff controls which would generate increased peak flow rates at storm drainage problem areas would, by definition, be precluded from successful attempts to prove "no harm," except in conjunction with proposed capacity improvements for the problem areas consistent with § 8-223, Subsection 13.

B. Any "no harm" justifications shall be submitted by the developer as part of the drainage plan submission per Subpart E. Developers submitting "no harm" justifications must still meet all of the water quality requirements in §§ 8-227, 8-228 and 8-229.

12. Regional Detention Alternatives. For certain areas within the study area, it may be more cost-effective to provide one control facility for more than one development site than to provide an individual control facility for each development site. The initiative and funding for any regional runoff control alternatives are the responsibility of prospective developers. The design of any regional control basins must incorporate reasonable development of the entire upstream watershed. The peak outflow of a regional basin would be determined on a case-by-case basis using the hydrologic model of the watershed consistent with protection of the downstream watershed areas. "Hydrologic model" refers to the calibrated version of the Penn State Runoff Model as developed for the stormwater management plan.

13. Capacity Improvements. In certain instances, primarily within the provisional or conditional no detention areas, local drainage conditions may dictate more stringent levels of runoff control than those based upon protection of the entire watershed. In these instances, if the developer could prove that it would be feasible to provide capacity improvements to relieve the capacity deficiency in the local drainage network, then the capacity improvements could be provided by the developer in lieu of runoff controls on the development site. Peak flow calculations are to be done assuming that the local watershed is in the existing condition and then assuming that the local watershed is developed per current zoning and using the specified runoff controls. Any capacity improvements would be designed using the larger of the above peak flows and the capacity criteria specified in Subsection 3. All new development in the entire subarea(s) within which the proposed development site is located shall be assumed to implement the developer's proposed discharge control, if any. Capacity improvements may also be provided as necessary to implement any regional detention alternatives or to implement a modified "no harm" option which proposes specific capacity improvements to provide that a less stringent discharge control would not create any harm downstream.

14. (Reserved)

15. (Reserved)

16. No portion of a site may be regraded between the Catasauqua or Hokendauqua watershed and any adjacent watershed except as part of a no-harm or hardship waiver procedure.

17. For development sites proposed to take place in phases, all detention ponds shall be designed to meet the applicable release rate(s) applied to all site areas tributary to the proposed pond discharge direction. All site tributary areas will be assumed as developed, regardless of whether all site tributary acres are proposed for development at that time. An exception shall be sites with multiple detention ponds in series where only the downstream pond must be designed to the stated release rate.

§ 8-223.1 Natural or Man-Made Channels or Swales.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; and by Ord. No. 2022-03, 10/25/2022]

Applicants shall provide a comparative pre- and post-construction stormwater management hydrograph analysis for each direction of discharge and for the site overall to demonstrate compliance with the provisions of this Part.

§ 8-224 Calculation Methodology.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; by Ord. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

1. Stormwater runoff from all development sites shall be calculated using either the rational method or a Soil Cover Complex methodology.

2. The design of any detention basin intended to meet the requirements of this Part shall be verified by routing the design storm hydrograph through the proposed basin using the storage indication method or other methodology demonstrated to be more appropriate. For basins designed using the rational method technique, the design hydrograph for routing shall be either the Universal Rational Hydrograph or the modified rational method trapezoidal hydrograph which maximizes detention volume. Use of the modified rational hydrograph shall be consistent with the procedure described in Section "PIPE.RAT" of the Users' Manual for the Penn State Urban Hydrograph Method (1987).

3. All stormwater detention facilities shall provide a minimum 1.0 foot freeboard above the maximum pool elevation associated with the two- through twenty-five-year runoff events. A 0.5 foot freeboard shall be provided above the maximum pool elevation of the 100-year runoff event. The freeboard shall be measured from the maximum pool elevation to the invert of the emergency spillway. The two- through 100-year storm events shall be controlled by the primary outlet structure. An emergency spillway for each basin shall be designed to pass the 100-year return frequency storm peak basin inflow rate with a minimum 0.5 foot freeboard measured to the top of basin. The freeboard criteria shall be met considering any off-site areas tributary to the basin as developed, as applicable. If this detention facility is considered to be a dam as per DEP Chapter 105, the design of the facility must be consistent with the Chapter 105 regulations, and may be required to pass a storm greater than the 100-year event.

4. The minimum circular orifice diameter for controlling discharge rates from detention facilities shall be three inches. Designs where a lesser size orifice would be required to fully meet release rates shall be acceptable with a three-inch orifice, provided that as much of the site runoff as practical is directed to the detention facilities. The minimum three-inch diameter does not apply to the control of the WQv.

5. Runoff Calculations Using the Soil Cover Complex Method.

A. Runoff calculations using the Soil Cover Complex Method shall use the Natural Resources Conservation Service Type II twenty-four-hour rainfall distribution. The twenty-four-hour rainfall depths for the various return periods to be used consistent with this Part may be taken from NOAA Atlas 14, Volume 2, Version 2.1, 2004, or the PennDOT Intensity — Duration — Frequency Field Manual (PDT-IDF) (May 1986) for Region 4. The following values are taken from the PDT-IDF Field Manual:

Return Period	24-Hour Rainfall Depth (inches)
1-year	2.40
2-year	3.00
5-year	3.60
10-year	4.56
25-year	5.52
50-year	6.48
100-year	7.44

B. A graphical and tabular presentation of the Type II twenty-four-hour distribution is included in Appendix C.[1]

[1] Editor's Note: Appendix C is included as an attachment to this chapter.

6. Runoff calculations using the rational method shall use rainfall intensities consistent with appropriate times of concentration and return periods and NOAA Atlas 14, Volume 2, Version 2.1, 2004, or the Intensity-Duration-Frequency Curves as presented in Appendix C.

7. Runoff curve numbers (CNs) to be used in the Soil Cover Complex Method shall be based upon the matrix presented in Appendix C.

8. Runoff coefficients for use in the rational method shall be based upon the table presented in Appendix C.

9. (Reserved)

10. All predevelopment calculations for a given discharge direction shall be based on a common time of concentration considering both on-site and any off-site drainage areas. All post-development calculations for a given discharge direction shall be based on a common time of concentration considering both on-site and any off-site drainage areas.

11. The Manning Equation shall be used to calculate the capacity of regular engineered watercourses. Standard engineering practice shall be used to calculate the capacity of irregular channels or watercourses. Manning "n" values used in the calculations shall be consistent with the table presented in Appendix C. Pipe capacities shall be determined by methods acceptable to the Township Engineer.

12. The Pennsylvania DEP, Chapter 105, Rules and Regulations, apply to the construction, modification, operation or maintenance of both existing and proposed dams, water obstructions and encroachments throughout the watershed. Criteria for design and construction of stormwater management facilities according to this Part may not be the same criteria that are used in the permitting of dams under the Dam Safety Program. The designer shall meet the requirements of this Part and Chapter 105.

13. All time of concentration calculations shall use a segmental approach which may include one or all of the flow types below:

A. Sheet flow (overland flow) calculations shall use either the NRCS average velocity chart (Figure 3-1, Technical Release-55, 1975) or the modified kinematic wave travel time equation (equation 3-3, NRCS TR-55, June 1986). If using the modified kinematic wave travel time equation, the sheet flow length shall be limited to 50 feet for designs using the rational method and limited to 150 feet for designs using the Soil-Cover-Complex Method.

B. Shallow concentrated flow travel times shall be determined from the watercourse slope, type of surface and the velocity from Figure 3-1 of TR-55, June 1986.

C. Open channel flow travel times shall be determined from velocities calculated by the Manning Equation. Bankfull flows shall be used for determining velocities. Manning "n" values shall be based on the table presented in Appendix C.

D. Pipe flow travel times shall be determined from velocities calculated using the Manning Equation assuming full flow and the Manning "n" values from Appendix C.

14. If using the rational method, all predevelopment calculations for a given discharge direction shall be based on a common time of concentration considering both on-site and any off-site drainage areas. If using the rational method, all post-development calculations for a given discharge direction shall be based on a common time of concentration considering both on-site and any off-site drainage areas.

15. Impervious coverage for stormwater management designs for any subdivision creating one or more new lots shall utilize the maximum impervious coverage allotted for the individual lots as defined within the Township's Zoning Ordinance.[2]

[2] Editor's Note: See Ch. 27, Zoning.

§ 8-225 Permit Requirements by Other Government Agencies.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; by Ord. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

The following permit requirements apply to certain regulated and earth disturbance activities and must be met prior to commencement of regulated and earth disturbance activities, as applicable:

1. All regulated and earth disturbance activities subject to permit requirements by DEP under regulations at 25 Pa. Code Chapter 102.

2. Work within natural drainageways subject to permit by DEP under 25 Pa. Code Chapter 102.

3. Any stormwater management facility that would be located in or adjacent to surface waters of the commonwealth, including wetlands, subject to permit by DEP under 25 Pa. Code Chapter 105.

4. Any stormwater management facility that would be located on a state highway right-of-way or require access from a state highway shall be subject to approval by the Pennsylvania Department of Transportation (PennDOT).

5. Culverts, bridges, storm sewers or any other facilities which must pass or convey flows from the tributary area and any facility which may constitute a dam subject to permit by DEP under 25 Pa. Code Chapter 105.

§ 8-226 Erosion and Sediment Control During Regulated Earth Disturbance Activities.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; by Ord. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

1. No regulated earth disturbance activities within the Township shall commence until approval by the Township of an erosion and sediment control plan for construction activities. Written approval by DEP or a delegated County Conservation District shall satisfy this requirement.

2. An erosion and sediment control plan is required by DEP regulations for any earth disturbance activity of 5,000 square feet or more under 25 Pa. Code § 102.4(b).

3. A DEP NPDES stormwater discharges associated with construction activities permit is required for regulated earth disturbance activities under 25 Pa. Code Chapter 92.[1]

[1] Editor's Note: Former Title 25, Chapter 92, of the Pennsylvania Code was reserved October 9, 2010. See now 25 Pa. Code § 92a.1 et seq.

4. Evidence of any necessary permit(s) for regulated earth disturbance activities from the appropriate DEP regional office or County Conservation District must be provided to the Township before the commencement of an earth disturbance activity.

5. A copy of the erosion and sediment control plan and any permit, as required by DEP regulations, shall be available at the project site at all times.

§ 8-227 Water Quality Requirements.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2005-06, 3/22/2005; by Ord. No. 2006-07, 8/22/2006; by Ord. No. 2007-03, 7/12/2007; Ord. No. 2019-03, 7/23/2019; and by Ord. No. 2022-03, 10/25/2022]

1. No regulated earth disturbance activities within the Township shall commence until approval by the Township of a drainage plan which demonstrates that the earth disturbance will be done in compliance with this Part.

2. The water quality volume (WQv) shall be captured and treated. The WQv shall be calculated two ways. First, WQv shall be calculated using the following formula:

WQv =

(c)(P)(A) ————— 12

Where:
WQv	=	Water quality volume in acre-feet.
C	=	Rational method post-development runoff coefficient for the two-year storm.
P	=	1.25 inches.
A	=	Area in acres of proposed regulated activity.

3. The WQv shall be calculated for each post-development drainage direction on a site for sizing BMPs. Areas of the site having no impervious cover and no proposed earth disturbance activity during development may be excluded from the WQv calculations and do not require treatment.

A. Second, the WQv shall be calculated as the difference in runoff volume from predevelopment to post-development (without taking into consideration engineered infiltration volumes) for the two-year, twenty-four-hour return period storm using TR-55 methodology (based on CN, S, and P values). The effect of closed depressions on the site shall be considered in this calculation. The larger of these two calculated volumes shall be used as the WQv to be captured and treated, except that in no case shall the WQv be permitted to exceed 1.25 inches of runoff over the site area. This standard does not limit the volume of infiltration a developer may propose for purposes of water quantity/peak rate control.

4. If a developer is proposing to use a dry extended detention facility, wet pond, constructed wetland, or other BMP that ponds water on the land surface and may receive direct sunlight, the discharge from that BMP must be treated by infiltration, a vegetated buffer, filter strip, bioretention, vegetated swale or other BMP that provides a thermal benefit to protect the high quality waters of the commonwealth from thermal impacts.

5. The WQv for a site as a result of the regulated activities must either be treated with infiltration or two acceptable BMPs such as those listed in Subsection 6, except for minor areas on the periphery of the site that cannot reasonably be drained to an infiltration facility or other BMP.

6. If infiltration of the entire WQv is not proposed, the remainder of the WQv shall be treated by two acceptable BMPs in series for each discharge location. Sheet flow draining across a pervious area can be considered as one BMP. Sheet flow across impervious areas and concentrated flow shall flow through two BMPs. If sheet flow from an impervious area is to be drained across a pervious area as one BMP, the length of the pervious area must be equal to or greater than the length of impervious area. Acceptable BMPs are listed below and shall be designed in accordance with the latest edition of the Stormwater Best Management Practices Manual as issued by the Pennsylvania Department of Environmental Protection.

Best Management Practice

Bioretention^A

Capture reuse^B

Constructed wetlands

Dry extended detention ponds

Minimum disturbance/minimum maintenance practices

Significant reduction of existing impervious cover

Stormwater filters^A (sand, peat, compost, etc.)

Vegetated buffers/filter strips

Vegetated roofs

Vegetated swales^A

Water quality inlets^C

Wet detention ponds

NOTES:
A	This BMP could be designed with or without an infiltration component. If infiltration is proposed, the site and BMP will be subject to the testing and other infiltration requirements in this Part.
B	If this BMP is used to treat the entire WQv, then it is the only BMP required, because of this BMP's superior water quality performance.
C	Water quality inlets include such BMPs as oil/water separators, sediment traps/catch basin sumps, and trash/debris collectors in catch basins.

7. BMPs designed to store or infiltrate runoff and discharge to surface runoff or pipe flow shall provide storage volume for the full WQv below the lowest outlet invert.

8. In no case shall the same BMP be employed consecutively to meet the requirements of this Part.

9. Stormwater runoff from hot spot land uses shall be pretreated prior to discharge, and/or receiving treatment for WQv as required by other sections of this Part.

A. Acceptable methods of pretreatment are listed below.

Hot Spot Land Use	Pretreatment Method(s)
Vehicle maintenance and repair facilities including auto parts stores	Water quality inlets
	Use of drip pans and/or dry sweep material under vehicles/equipment
	Use of absorbent devices to reduce liquid releases
	Spill prevention and response program
Vehicle fueling stations	Water quality inlets
	Spill prevention and response program
Storage areas for public works	Water quality inlets
	Use of drip pans and/or dry sweep material under vehicles/equipment
	Use of absorbent devices to reduce liquid releases
	Spill prevention and response program
	Diversion of stormwater away from potential contamination areas
Outdoor storage of liquids	Spill prevention and response program
Commercial nursery operations	Vegetated swales/filter strips
	Constructed wetlands
	Stormwater collection and reuse
Salvage yards and recycling facilities*	BMPs that are a part of a stormwater pollution prevention plan under an NPDES permit
Fleet storage yards and vehicle cleaning facilities*	BMPs that are a part of a stormwater pollution prevention plan under an NPDES permit
Facilities that store or generate regulated substances*	BMPs that are a part of a stormwater pollution prevention plan under an NPDES permit
Marinas*	BMPs that are a part of a stormwater pollution prevention plan under an NPDES permit
Certain industrial uses (listed under NPDES)*	BMPs that are a part of a stormwater pollution prevention plan under an NPDES permit

NOTES:
*	Regulated under the NPDES Stormwater Program.

B. Design references for the pretreatment methods, as necessary, are listed below. If the developer can demonstrate to the satisfaction of the Township that the proposed land use is not a hot spot, then the pretreatment requirement would not apply.

Pretreatment Method	Design ReferenceA
Constructed wetlands	4, 5, 8, 10, 16
Diversion of stormwater away from potential contamination areas	4, 11
Stormwater collection and reuse (especially for irrigation)	4, 14
Stormwater filters (sand, peat, compost, etc.)	4, 5, 10, 16
Vegetated swales	2, 3, 5, 11, 16, 17
Water quality inlets	4, 7, 15, 16, 19

NOTES:
A	These numbers refer to the Design Reference Title Chart in § 8-227, Subsection 6, above.

10. The use of infiltration BMPs is prohibited on hot spot land use areas.

11. The Township may, after consultation with DEP, approve alternative methods for meeting the state water quality requirements other than those in this section, provided that they meet the minimum requirements of and do not conflict with state law, including but not limited to the Clean Streams Law.[1]

[1] Editor's Note: See 35 P.S. § 691.1 et seq.

12. Any amount of volume infiltrated can be subtracted from the WQv to be treated by noninfiltration BMPs.

13. Soil amendments and aboveground BMPs (as defined in the latest edition of the Pennsylvania Department of Environmental Protection's Stormwater Best Management Practices Manual) are prohibited on residential lots of one acre in size or smaller. These BMPs may be allowed on lots greater than one acre, provided that a minimum contiguous area of one acre is provided around the dwelling and that this minimum contiguous area of one acre contains no other form of stormwater BMP.

§ 8-228 Post-Construction Recharge Volume Criteria.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2007-03, 7/12/2007; and by Ord. No. 2022-03, 10/25/2022]

1. The recharge volume (REv) for each subarea shall be captured and treated during the two-year, five-minute storm event. This treatment is required regardless of the site's stormwater management district or the developer's proposed means of stormwater control (infiltration, detention or "no harm").

2. If a site has both carbonate and noncarbonate areas, the developer shall investigate the ability of the noncarbonate portion of the site to fully meet the requirements for REv for the whole site through infiltration. If that proves infeasible, or if the site is entirely composed of carbonate areas, infiltration in the carbonate area or two other noninfiltration BMPs must be used. No infiltration practice in the noncarbonate area shall be located within 50 feet of a boundary with carbonate bedrock, except when a preliminary site investigation has been done showing the absence of special geologic features within 50 feet of the proposed infiltration practice.

3. For entirely noncarbonate sites, the recharge volume (REv) shall be infiltrated unless the developer demonstrates that it is infeasible to infiltrate the REv for reasons of seasonal high water table, permeability rate, soil depth or isolation distances; or except as provided in § 8-227, Subsection 1.

A. The recharge volume (REv) shall be calculated as follows:

REv = (0.25)*(I)/12
Where:
REv	=	Recharge volume in acre-feet.
I	=	Impervious area in acres.

B. Any amount of the REv infiltrated can be subtracted from the WQv to be treated by noninfiltration BMPs.

C. If it is not feasible to infiltrate the full REv, the developer shall infiltrate the maximum portion of the REv that is feasible based on the site characteristics. Whatever portion of the REv is not infiltrated shall be captured and treated as WQv, as calculated elsewhere in this Part.

§ 8-229 Stormwater Infiltration Requirements.

[Ord. No. 98-3, 2/25/1998; as amended by Ord. No. 2007-03, 7/12/2007; by Ord. No. 2019-03, 7/23/2019; and by Ord. No. 2022-03, 10/25/2022]

1. Stormwater Runoff Volume Control Facilities. Where the geology, soils and site constraints (isolation distances, etc.) of a development site are suitable, the recharge volume (REv) shall be infiltrated. Site suitability shall be determined by the following requirements:

A. Geologic Features.

(1) For each proposed regulated activity in the watershed, the developer shall conduct and document a preliminary site investigation on the site for possible infiltration practices, including gathering data on the soil and bedrock type(s) present on the site from published sources, a field inspection of the site, a minimum of one test pit and a minimum of two percolation tests, as outlined in this Part. This investigation will determine depth to bedrock, depth to the seasonal high water table, soil permeability, and location of special geologic features, if applicable. This study and any recommendations therefrom shall be prepared by a qualified geotechnical professional. This study is subject to review by the Township.

(2) The location(s) of special geologic features, including any apparent boundaries between carbonate and noncarbonate bedrock, shall be verified by a qualified geotechnical professional.

(3) The qualified geotechnical professional shall issue his/her opinion on:

(a) The suitability of the individual infiltration practices to infiltrate.

(b) The limiting zone of each infiltration practice.

(c) The infiltration rate of each infiltration practice.

(d) The presence of all special geologic features.

B. For entirely noncarbonate sites, the REv shall be infiltrated unless the developer demonstrates that it is infeasible to infiltrate for reasons of seasonal high water table, permeability rate, soil depth, or isolation distances. If it is not feasible to infiltrate the full REv, the applicant shall infiltrate that portion of the REv that is feasible based on the site characteristics. If none of the REv can be infiltrated, REv shall be considered as part of the WQv and shall be captured and treated as described in § 8-227, Subsection 6.

C. Infiltration.

(1) In carbonate areas, in addition to the testing required in § 8-229, Subsection 1A, the preliminary site investigation shall include an assessment of the remainder of the site for possible infiltration based on required isolation distances from special geologic features and the likely soil depth and permeability based on published data or other site data available. The soil depth, percolation rate and proposed loading rate, each determined as described in this Part, along with the buffer from special geologic features shall be compared to the Recommendation Chart for Infiltration Stormwater Management BMPs in Carbonate Bedrock in Appendix D[1] to determine if the site is recommended for infiltration.

[1] Editor's Note: Appendix D is included as an attachment to this chapter.

(2) Developers are encouraged to infiltrate the stormwater runoff, as calculated in this Part, but are not required to use infiltration BMPs on a carbonate site even if the site falls in the "recommended" range on the chart in Appendix D, if the entire site is deemed unsuitable for infiltration based upon the site evaluation described in this Part.

(3) If it is not feasible to infiltrate the full REv, the developer shall infiltrate that portion of the REv that is feasible based on the site characteristics.

D. Sites with Carbonate and Noncarbonate Areas.

(1) If a site has both carbonate and noncarbonate areas, the developer shall investigate the ability of the noncarbonate portion of the site to fully meet the requirements of this Part for infiltration of the REv for the whole site. If that proves infeasible, the developer shall perform the preliminary site investigation for the carbonate area to determine the appropriate design strategy.

(2) If it is not feasible to infiltrate the full REv, the developer shall infiltrate that portion of the REv that is feasible based on the site characteristics.

E. The preliminary site investigation shall continue on different areas of the site until a suitable infiltration location is found or the entire site is determined to be unsuitable for infiltration.

F. For proposed infiltration practices:

(1) The additional site investigation and testing, as outlined in Appendix G,[2] shall be completed.

[2] Editor's Note: Appendix G is included as an attachment to this chapter.

(2) The site must meet all required vertical and horizontal isolation distances.

G. The Township may determine infiltration to be infeasible if there are known existing conditions or problems that may be worsened by the use of infiltration.

2. For proposed infiltration practices that appear feasible based on the preliminary site investigation, the developer shall conduct the additional site investigation and testing as outlined in Appendix G[3] (see also § 8-229, Subsection 9C). This testing must be performed and evaluated by the developer's qualified geotechnical professional and be field verified by the Township Engineer or their designee. The qualified geotechnical professional will provide a report to the Township documenting his findings. This report is subject to review by the Township. The soil depth, percolation rate and proposed loading rate, each weighted as described in § 8-229, Subsection 9I, along with the buffer from special geologic features shall be provided; if the infiltration practice is proposed in an area of carbonate geology, these volumes shall be compared to the Recommendation Chart for Infiltration Stormwater Management BMPs in Carbonate Bedrock in Appendix D[4] to determine if the site is recommended for infiltration. The location of each soil probe and a description of the soil profile and characteristics shall be provided on the preliminary subdivision or land development plans, or final plans and/or site plans.

[3] Editor's Note: Appendix G is included as an attachment to this chapter.

[4] Editor's Note: Appendix D is included as an attachment to this chapter.

3. If a site has both carbonate and noncarbonate areas, no infiltration practice in the noncarbonate area shall be located within 50 feet of a boundary with carbonate bedrock, except when a preliminary site investigation has been done showing the absence of special geologic features within 50 feet of the proposed infiltration practice.

4. If infiltration is proposed in carbonate areas, the post-development two-year runoff volume leaving the site shall be 80% or more of the predevelopment runoff volume for the carbonate portion of the site to prevent infiltration of volumes far in excess of the predevelopment infiltration volume.

5. Site areas proposed for infiltration shall be protected from disturbance and compaction except as necessary for construction of infiltration practices.

6. Stormwater infiltration practices shall not be placed in or on a special geologic feature(s). Additionally, stormwater runoff shall not be discharged into existing on-site sinkholes.

7. Developers shall request, in writing, public water suppliers to provide the Zone I wellhead protection radius, as calculated by the method outlined in the Pennsylvania Department of Environmental Protection wellhead protection regulations, for any public water supply well within 400 feet of the site. Infiltration is prohibited in the Zone I radius as defined and substantiated by the public water supplier in writing. If the developer does not receive a response from the public water supplier, the Zone I radius is assumed to be 400 feet.

8. Soil.

A. Soil thickness is to be measured from the bottom of any infiltration system proposed in an area of carbonate geology. The effective soil thickness in the Recommendation Chart for Infiltration Stormwater Management BMPs in Carbonate Bedrock in Appendix D[5] is the measured soil thickness multiplied by the thickness factor based on soil permeability (as measured by the adapted 25 Pa. Code § 73.15 percolation test in Appendix G[6]), as follows:

Permeability Range*	Thickness Factor
6.0 to 12.0 inches/hour	0.8
2.0 to 6.0 inches/hour	1.0
1.0 to 2.0 inches/hour	1.4
0.75 to 1.0 inches/hour	1.2
0.5 to 0.75 inches/hour	1.0

NOTES:
*	If the permeability rate (as measured by the adapted 25 Pa. Code § 73.15 percolation test in Appendix G) falls on a break between two thickness factors, the smaller thickness factor shall be used.

[5] Editor's Note: Appendix D is included as an attachment to this chapter.

[6] Editor's Note: Appendix G is included as an attachment to this chapter.

B. Soil permeability of infiltration practices shall be measured by the adapted 25 Pa. Code § 73.15 percolation test in Appendix G.

9. The requirements and standards for these infiltration practices are as follows:

A. All infiltration designs shall be subject to review by the Township Engineer.

B. The following minimum vertical and horizontal isolation distances shall be maintained from the edge of an infiltration practice to the following items:

(1) Vertical Isolation Distance:

(a) Depth to bedrock below the invert of the infiltration practice shall be greater than or equal to 24 inches.

(b) Depth to seasonal high water table below the invert of the infiltration practice shall be greater than or equal to 36 inches; except for infiltration of residential roof runoff where the seasonal high water table must be below the invert of the infiltration practice. (If the depth to bedrock is between two and three feet and the evidence of the seasonal high water table is not found in the soil, no further testing to locate the depth to seasonal high water table is required.)

(2) Horizontal Isolation Distance:

Improvement or Boundary or Feature		Minimum Separation — Distances (feet)
		For Runoff From Single-Family Detached Dwelling Roofs and Driveways	For Runoff From Any Other Source Such as Public Roads, Multifamily Developments and Nonresidential Developments
a.	Property line	40*	100*
b.	Building foundation if system is downgradient or sidegradient	15	20***
c.	Building foundation if system is upgradient	50	50***
d.	Onlot sewage disposal drainfield	25	50
e.	Private water supply well	100	100
f.	Public water supply well	400	400
g.	Geologic contact with carbonate bedrock**	50	50
h.	Road right-of-way line	20****	50****

NOTES:
*	This setback may be reduced to 10 feet if documentation is provided to show that all setbacks from wells, foundations and drainfields on neighboring properties can be met.
**	Unless a preliminary site investigation is done in the carbonate bedrock to show the absence of special geologic features within 50 feet of the proposed infiltration use.
***	Where the building setbacks from a public infiltrator are more restrictive than the zoning setback, the new setback line shall be shown, with an appropriate dimension provided from the infiltration practice, on any plan which shows zoning setbacks.
****	No setback is required from right-of-way on a newly proposed road where infiltration practices are proposed to be designed in accordance with the design standards of this Part and it can be shown that no other required setbacks are violated.

C. Soil Permeability.

(1) Soil permeability (as measured by the adapted 25 Pa. Code § 73.15 percolation test in Appendix G[7]) in the area of the infiltration practice (for areas other than runoff from single-family dwelling roofs) must be greater than or equal to 0.5 inch/hour and less than or equal to 12 inches per hour, except where a soil permeability greater than 12.0 inches/hour is allowed as indicated in Appendix G.

[7] Editor's Note: Appendix G is included as an attachment to this chapter.

(2) Soil evaluation and infiltration testing for each BMP shall be as prescribed in the PA DEP Stormwater Best Management Practices Manual. Notwithstanding the requirements contained therein, a minimum of two test pits shall be conducted for each BMP up to 1/2 acre in size. BMPs that are larger than 1/2 acre in size shall have multiple test pits that are evenly distributed at the rate of four to six tests per acre of BMP area. Infiltration/permeability testing shall be conducted in each test pit as per the PA DEP Stormwater Best Management Practices Manual.

D. The contact area between the infiltration practice and the soil shall be level.

E. Infiltration practices shall not be constructed on fill unless the applicant demonstrates that the fill is stable and otherwise meets the infiltration BMP standards of this Part.

F. No infiltration practice shall be designed to recharge stormwater runoff from a contributing watershed larger than two acres.

G. The capture and conveyance of stormwater to an infiltration structure shall meet the following minimum standards:

(1) For stormwater runoff from a single lot and infiltrated on the same lot:

(a) From buildings: gutters, downspouts, four-inch minimum diameter PVC pipe. (Schedule 40 PVC, or equal, under driveways.)

(b) From driveways: trench grate (Poly-drain, manufactured by ABT, Inc., or equal) or a yard catch basin may be utilized to capture driveway runoff and four-inch-diameter PVC conveyance pipe. (Schedule 40 PVC, or equal, under driveway.) Both trench grates and yard inlets must be located beyond the ultimate road rights-of-way.

(2) Underground conveyance pipe shall have a minimum pitch of 1/4 inch per foot. For stormwater runoff from a public road and/or from one lot and being infiltrated on another lot for facilities that will be privately owned and maintained:

(a) Capture stormwater by way of standard Type C or Type M inlets or by way of manholes designed and constructed in accordance with PennDOT specifications and standard drawings, with bicycle-safe grates.

(b) Each inlet shall be provided with a sump under the lowest outlet pipe invert of 24 inches or more in depth, depending on the solids capacity required. This inlet may have a perforated design if the inlet is designed to be part of an infiltration structure.

(c) Each inlet shall be provided with a removable hood (also known as a "snout") designed to help retain floatables. This hood and slide rail system shall be constructed of stainless steel or cast iron, or an alternate material, if approved by the Township. For inlets intended to be "perforated," no removable hood is necessary.

(3) For stormwater runoff from a public road and adjacent private property, for facilities that will be dedicated to and accepted by the Township:

(a) Capture stormwater by way of standard Type C or Type M inlets designed and constructed in accordance with PennDOT specifications, with bicycle-safe grates. For the capture of stormwater in grass or paved swale conditions, there shall be one Type M inlet and one Type C inlet at each point of capture.

(b) Each inlet shall be provided with a sump under the lowest outlet pipe invert of 24 inches or more in depth, depending on the solids capacity required. This inlet shall not have perforated sides and shall not be used as part of an infiltration structure.

(c) Each inlet shall be provided with a removable hood (also known as a "snout") designated to help retain floatables. This hood and slide rail system shall be constructed of stainless steel or cast iron or alternate material, if approved by the Township.

(d) The capture inlets shall be connected to one or more infiltration manholes with standard cast iron manhole frames and covers located five feet outside the public road right-of-way in a designated drainage easement. The infiltration manholes shall be designed and constructed in accordance with PennDOT specifications and standard drawings. These manholes shall not be perforated but shall be connected to storm sewer piping which is perforated. Each manhole shall be provided with a sump (under the lowest outlet pipe invert) of 24 inches or more in depth, depending on the solids capacity required.

(e) The required design layout is shown in Appendix D-2 and Appendix D-3,[8] as attached hereto and made a part thereof.

[8] Editor's Note: Appendix D-2 and D-3 are included as attachments to this chapter.

H. For stormwater infiltration systems proposed along existing or proposed roads, the maximum spacing between separate inlets shall be 400 feet along the shoulder or curbline. Each such inlet shall be provided with its own separate infiltration structure to provide a distributed method of stormwater recharge.

I. Infiltration Structures.

(1) All infiltration area loading rates (the ratio of the land area draining to the infiltration area, as modified below, compared to the area of contact between the infiltration area storm and soil) shall not exceed 500% calculated as follows, unless a faster absorption rate is proven by percolation testing, conducted at the location and elevation of the proposed contact area:

[Area Tributary to the Infiltration Structure] x 100%

[Absorption Area of below the Infiltration Structure]

(2) The area tributary to the infiltration structure shall be weighted as follows:

(a) All disturbed areas to be made impervious: weight at 100%.

(b) All disturbed areas to be made pervious: weight at 50%.

(c) All undisturbed pervious areas: weight at 0%.

(d) All existing impervious areas: weight at 100%.

(3) Any percolation testing conducted to prove a faster percolation rate must be conducted by the developer's geologist, soil scientist or engineer and shall be subject to the review of the Township Engineer.

J. All infiltration structures shall be provided with spillover points and/or design features in case of clogging or overcapacity of the infiltration structure. This spillover water shall be directed away from any structures and directed in a safe manner toward areas designed or recognized for a 100-year stormwater conveyance. The conveyance and distribution of spillover stormwater shall be designed in accordance with all stormwater management regulations of the Township. If the resulting design includes provisions for standing water in a sump condition, the design criteria for detention basins, including safety provisions associated with detention basins, as described in § 8-231 of this Part shall be followed.

K. A plot plan prepared to an accurate engineer's or surveyor's scale, suitable for an onlot sewage disposal system design or suitable for the building permit application, shall be provided to the Township Engineer and Zoning Officer for review of each application for a building permit, driveway permit, or land development for any applicant proposing to utilize infiltration structures for stormwater management. The infiltration structure design can be incorporated into the onlot sewage disposal system design plot plan.

(1) The plot plan shall show the following existing and/or proposed features: all soil trench and test locations and soil trench and test results, building(s), storm drainage facilities, sewage disposal systems, alternate sewage disposal system test site, well, driveway, accessory buildings, and contours, etc. This plan shall be accompanied by design calculations and construction details for any proposed infiltration structure. The design of the infiltration structure shall be reviewed by the Township Engineer.

(2) The plot plan shall also contain lot lines with dimensions, easements, North arrow, street(s) with name(s), waterways, springs, creeks, ponds, floodplain, wetlands and all features applicable to any required isolation distance.

L. Construction of Infiltration Structures.

(1) The Township Engineer shall be notified 72 hours prior to the excavation of an infiltration structure so the Engineer (or its designee) can schedule an on-site visit to verify the size of the excavation in accordance with the plan and calculations.

(2) Excavation of the infiltration structure shall be the size and depth as shown on the above-mentioned plot plan.

(3) The drainage portion of the excavation shall be filled with AASHTO No. 3 Crushed Aggregate (equivalent to 40% voids volume). Slag shall not be permitted as aggregate for infiltration structures.

(4) For single-family detached lot infiltration structures, a four-inch perforated vertical inspection standpipe shall be installed in the drainage aggregate for the full depth of the pit and connected to the inlet pipe(s). A cap shall be placed on the standpipe at finished grade.

(5) For single-family detached lot infiltration structures, precast seepage pit rings with the Department of Environmental Protection (DEP) approved precast lids may be utilized to obtain required storage volume. A vertical inspection standpipe shall be installed full depth in the aggregate outside the seepage ring or from the precast lid if the inlet pipe penetrates the seepage ring. The area between the precast seepage ring and the excavated sidewalls shall be backfilled with AASHTO No. 3 crushed aggregate.

(6) All infiltration structure aggregate shall be encapsulated in a layer of geotextile fabric meeting the requirements of the PennDOT Publication 408, Section 735, Construction Class 1.

(7) All infiltration structures shall be covered with at least one foot of cover material, except for those components of the structure that extend to the surface of the ground.

M. Inspection and certification for infiltration structures receiving runoff from one lot and infiltrating stormwater on the same lot:

(1) The Township Engineer, as directed by the Allen Township Board of Supervisors, shall perform the inspection of the infiltration structure excavation for size, depth and location requirements.

(2) The lot owner shall provide the Township Engineer with a certification of completion stating the infiltration structure and stormwater collection system(s) was installed in accordance with the approved plot plan and this Part. The certification shall be signed by the owner and the contractor who installed the infiltration structure(s) and collection and conveyance system. A copy of the delivery receipt for the crushed aggregate and seepage ring(s) or other type of structure shall be attached to the certification.

N. Inspection for infiltration structures receiving stormwater runoff from a public road and/or from one lot and being infiltrated on another lot:

(1) The Township Engineer shall inspect these structures and their associated capture and conveyance system in accordance with the requirements of a developer's improvements agreement and procedures established for land development improvements.

O. Fees.

(1) The fee for infiltration structure design review and inspection shall be established by the Township, by resolution, for each infiltration structure proposed.

(2) The fees are required to be paid prior to the issuance of a permit for any driveway, parking area, building or land development proposal using one or more infiltration structures for stormwater management.

P. A certificate of occupancy for a new driveway, parking area, building or land development on a lot planned for use of one or more infiltration structures as part of the stormwater management for that lot or designed to service that lot shall not be issued until the Township Engineer determines the infiltration structure size and location has been verified and the Township Engineer has received the certification of completion, as set forth in Subsection 9M(2) above, and/or determines that the off-site stormwater collection and conveyance system and infiltration structure(s) is (are) complete and operational.

§ 8-230 Riparian Buffers.

[Ord. No. 2022-03, 10/25/2022]

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 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 the Township and shall be recorded in the appropriate 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.

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.