Article III Applicability

§ 174-7 Applicability; regulated activities.

This chapter shall apply to all watersheds and areas in Tredyffrin Township. Additional standards for peak rate of runoff control shall apply if they are more stringent for areas within certain watersheds, subject to an adopted Act 167 Plan.

This chapter shall only apply to temporary erosion and sediment control measures and all permanent structural and nonstructural stormwater management BMPs constructed as part of any of the regulated activities listed in this section.

The following activities shall be regulated by this chapter unless exempted by § 174-8:

Subdivisions.

Land developments.

Redevelopments.

Construction of proposed, new or additional impervious surfaces (driveways, parking lots, roads, etc.).

(5)

Construction of proposed buildings or additions to existing buildings.

(6)

Alteration of the natural hydrologic regime.

(7)

Diversion, piping or encroachments in any natural or human-made drainage channel.

(8)

Installation of nonstructural and structural stormwater management BMPs or appurtenances thereto.

(9)

Earth disturbance activities, whether or not they are associated with a development or redevelopment project, of greater than 5,000 square feet where slopes less than or equal to 15% are impacted by grading, disturbance or construction activities.

(10)

Earth disturbance activities, whether or not they are associated with a development or redevelopment project, of greater than 1,000 square feet where slopes greater than 15% are impacted by proposed grading, disturbance or construction activities.

(11)

Earth disturbances within 50 feet of other sensitive environmental features, such as streams, ponds, lakes and wetlands.

(12)

Any of the above regulated activities which were approved more than five years prior to the effective date of this chapter (date of adoption) and resubmitted for municipal approval.

Table 7.1 summarizes the applicability requirements. "Proposed Impervious Surface" in Table 7.1 includes new, additional, or replacement impervious surface/cover. Repaving existing surfaces without reconstruction does not constitute "replacement."

TABLE 7.1
APPLICABILITY
	Type of Project	Proposed Impervious Surface				Earth Disturbance
	Type of Project	0 - 499 square feet	500 - 1,000 square feet	>1,000 square feet	>1 acre	5,000 square feet to 1 acre	>1 acre
Article IV, Drainage Plan Requirements	Development	Exempt	Modified	Yes	Yes	Yes	Yes
Article IV, Drainage Plan Requirements	Redevelopment	Exempt	Modified	Yes	Yes	Yes	Yes
§ 174-19, Nonstructural project design	Development	Exempt	Yes	Yes	Yes	Yes	Yes
§ 174-19, Nonstructural project design	Redevelopment	Exempt	Yes	Yes	Yes	Yes	Yes
§ 174-20, Groundwater recharge	Development	Exempt	Yes	Yes	Yes	Yes	Yes
§ 174-20, Groundwater recharge	Redevelopment	Exempt	Yes	Yes	Yes	Yes	Yes
§ 174-21, Water quality requirements	Development	Exempt	Exempt	Yes	Yes	n/a	Yes
§ 174-21, Water quality requirements	Redevelopment	Exempt	Exempt	Yes	Yes	n/a	Yes
§ 174-22, Stream bank erosion requirements	Development	Exempt	Exempt	Yes	Yes	n/a	Yes
§ 174-22, Stream bank erosion requirements	Redevelopment	Exempt	Exempt	Yes	Yes	n/a	Yes
§ 174-23, Stormwater peak rate control and management standards	Development	Exempt	Exempt	Yes	Yes	Yes	Yes
	Redevelopment	Exempt	Exempt	Yes	Yes	Yes	Yes
Erosion and sediment pollution control (E&SC) plan	Earth disturbance	See earth disturbance requirements	See earth disturbance requirements	See earth disturbance requirements	See earth disturbance requirements and NPDES permit requirements	Yes	Yes
Erosion and sediment pollution control (E&SC) plan	Earth disturbance	0 - 5,000 square feet: No SWG permit required from Township, but E&SC BMPs required to be implemented on site 0 - 1,000 square feet: SWG permit required from Township, with E&SC plan and BMPs if impacts slopes >15% 5,000 square feet: 1 acre — SWG permit required from Township, with E&SC plan and BMPs Greater than 1 acre: SWG permit required from Township, and NPDES permit required from CCCD and/or DEP (Refer to municipal earth disturbance requirements)				Yes	Yes

	LEGEND:
	Yes — Drainage plan with stormwater management controls necessary to meet the section provision.
	Exempt — Exempt from required section provision. Drainage plan submission may still be required if other section provisions are applicable (yes in box).
	Modified Drainage Plan — For sites with 500 square feet to 1,000 square feet of proposed impervious surfaces. This stormwater and grading permit (SWG) shall follow the groundwater recharge requirements found in § 174-20C(1)(b)[1].
	E&SC Plan — Erosion and sediment control pollution plans are required for earth disturbances greater than 5,000 square feet. E&SC plans are also required for earth disturbances greater than 1,000 square feet if impacts to slopes >15%.

§ 174-8 Exemptions.

Exemptions for land use activities. The following land use activities are exempt from the drainage plan submission requirements of this chapter:

(1)

Use of land for gardening for home consumption.

(2)

Agricultural activity when operated in accordance with a conservation plan, nutrient management plan, or erosion and sedimentation control plan approved by the County Conservation District. Installation of new or expansion of existing farmsteads, animal housing, waste storage, and production areas having a net increase of impervious surfaces greater than 1,000 square feet shall be subject to the provisions of this chapter.

(3)

Forestry operations which are following the Department of Environmental Protection's (DEP) management practices contained in its publication "Soil Erosion and Sedimentation Control Guidelines for Forestry," operating under an approved erosion and sedimentation plan and complying with the stream buffer requirements in § 174-21J.

(4)

Roadway replacement, development, or redevelopment that has less than 2,000 square feet of new, additional, or replaced impervious surface/cover, or in the case of earth disturbance only, less than 5,000 square feet of disturbance.

(5)

Proposed improvements not exceeding 499 square feet and where the total cumulative square footage of all impervious surfaces does not exceed the impervious surface standards of the applicable zoning district.

(6)

Maintenance to any existing stormwater management system made in accordance with plans and specifications approved by the Township Engineer.

(7)

Emergency maintenance work performed for the protection of public health, safety and welfare. A written description of the scope and extent of any emergency work performed shall be submitted to the Township Engineer within two calendar days of the commencement of the activity. If the Township Engineer finds that the work is not an emergency, then the work shall cease immediately and the requirements of this chapter shall be addressed as applicable.

(8)

Replacement of residential impervious coverage listed below is exempt from the provisions of this chapter:

(a)

Repair, maintenance, replacement, and/or resurfacing of existing asphalt, concrete, or impervious driveways. Relocation of existing driveways or reconstruction of driveways proposing additional impervious coverage exceeding 499 square feet are not exempt from the provisions of this chapter.

(b)

Repair, maintenance, or replacement of existing stone, concrete, or impervious patios, wooden or composite decks, and sidewalks. Relocation of existing decks, patios, or sidewalks, or reconstruction proposing additional impervious coverage exceeding 499 square feet, is not exempt from the provisions of this chapter.

(c)

Repair or maintenance to existing building structures, including interior and exterior renovations. Proposed building replacement projects, including complete rebuilds or partial knock-down rebuilds exceeding 499 square feet are not exempt from the provisions of this chapter.

(9)

Resurfacing and/or milling and resurfacing of existing roadway and highway impervious surfaces without reconstruction.

Exemptions for development activities.

(1)

The following development and earthmoving activities are exempt from the drainage plan submission requirements of this chapter:

(a)

Projects with up to a maximum of 499 square feet of new or additional proposed impervious surface.

(b)

Projects with up to a maximum of 5,000 square feet of disturbed earth.

(2)

These criteria shall apply to the total development even if the development is to take place in phases. The date of the chapter adoption shall be the starting point from which to consider tracts as "parent tracts" upon which future land development activities and respective earth disturbance computations shall be cumulatively considered.

Agricultural related activities.

[Added 10-7-2019 by Ord. No. HR-430[1]]

(1)

High tunnels (as defined in Article II) if:

(a)

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

(b)

The high tunnel meets one of the following:

[1]

The high tunnel is located at least 100 feet from any perennial stream or watercourse, public road or neighboring property line;

[2]

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%; or

[3]

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 the requirements of this chapter.

[1]

Editor's Note: This ordinance also redesignated former Subsection C as Subsection D.

Additional exemption criteria.

(1)

Exemption responsibilities. An exemption shall not relieve the applicant from implementing such measures as are necessary to protect public health, safety, and property.

(2)

HQ and EV streams. An exemption shall not relieve the applicant from meeting the special requirements for watersheds draining to identified high quality (HQ) or exceptional value (EV) waters and source water protection areas (SWPA) and requirements for nonstructural project design sequencing (see § 174-19).

(3)

Drainage problems. If a drainage problem is documented or known to exist downstream of or is expected to result from the proposed activity, then the Township may require the applicant to comply with this chapter.

(4)

Exemptions from provisions of this chapter still require compliance with all other applicable regulations.

§ 174-9 Compatibility with other ordinances or legal requirements.

Approvals issued pursuant to this chapter do not relieve the applicant of the responsibility to secure required permits or approvals for activities regulated by any other applicable code, rule, act, or ordinance.

Nothing in this chapter shall be construed to affect any of the Township's requirements regarding stormwater matters that do not conflict with the provisions of this chapter, such as local stormwater management design criteria (e.g., inlet spacing, inlet type, collection system design and details, outlet structure design, etc.).