The Trout Creek Stormwater Overlay District (TCS) is intended to provide for public stormwater improvements, in addition to the stormwater requirements of Chapter
174, the Stormwater Management Ordinance, in the Trout Creek watershed in a manner consistent with the 2010 Trout Creek Watershed Study and Stormwater Best Management Practice Analysis, as amended, and consistent with the 2009 Tredyffrin Township Comprehensive Plan, as amended. Such improvements may be stormwater management facilities, stream restoration or watershed improvements, or other related improvements deemed to be of public benefit to the community by the Board of Supervisors. The TCS is also intended to ensure that public stormwater improvements provide a clear defined reduction in the frequency and extent of downstream flooding and accelerated erosion, immediately downstream from a development site, and demonstrate improvement to impaired water bodies in the Township as defined by the Commonwealth of Pennsylvania in its current integrated list. Flexibility in granting waivers from Chapter
181, Subdivision and Land Development, to reduce impervious coverage and improve stormwater management will be encouraged.
The following provisions shall apply to the TCS:
A. The provisions of §§
208-162 and
208-163 in the TCS District are applicable only to parcels with an elevation no higher than 400 feet from sea level to ensure that public stormwater improvements would be effective within the Trout Creek Watershed, as delineated in Appendix A, that:
(1)
Provide the following minimum acreage:
(a)
Nonresidential parcels have a minimum lot area of five acres;
(b)
Residential parcels have a minimum lot area of 15 acres:
(2)
Provide access only to collector or arterial roads, as identified
in the Tredyffrin Township Comprehensive Plan of 2009, Table 2.7.1,
Roadway Functional Classification, as amended, excluding emergency
access.
(3)
Provide public stormwater improvements that:
(a)
Recharge, evapotranspirate, and/or provide on-site capture and
reuse of the total volume of stormwater generated by the proposed
development during the two-year/twenty-four-hour storm;
(b)
Exceed the baseline peak rate control requirements in §
174-23, Table 23.1, Stormwater Peak Rate Control and Management Standards, by at least 25% for all design storms (calculated before the application of any of the exemptions set forth in Chapter
174) from the proposed development condition; and
(c)
For development sites specifically identified in the 2010 Trout
Creek Stormwater Study, demonstrate compliance with the proposed rate
and quantity reductions identified in the final report.
B. For sites that were developed prior to adoption of this article and do not meet current stormwater requirements, impervious coverage may be increased 10% above the by-right limit of the underlying zoning district or the site's level of impervious coverage as of January 1, 2012, provided at least 25% of the site's existing impervious coverage is brought into compliance with the current stormwater requirements of Chapter
174, Stormwater Management. All additional proposed impervious coverage, such as but not limited to, parking lot expansion, building additions, etc., also must comply with the requirements of Chapter
174. If the site does not also comply with §
208-161A, then the provisions of §§
208-162 and
208-163 do not apply.
C. The TCS may be utilized as an overlay in all zoning districts, subject
to meeting the requirements of this article.
D. In the case of conflict between the provisions of requirements of this article and any other provision of Chapter
208, Zoning, the provisions of this article shall prevail.
E. The rate and volume control requirements of this article for public
stormwater improvements must be met on a project-wide or tract-wide
basis, as part of the conditional use application.
F. All stormwater management facilities, specifically including all public stormwater improvements, must be inspected according to the requirements of Chapter
174, Stormwater Management, and the plan approved pursuant to §
208-150A(11)(e) regarding maintenance responsibilities. Reports shall be submitted to the Township Engineer by January 30 of each year documenting all routine and nonroutine inspections, maintenance and repairs made to the public stormwater improvements for the previous calendar year and will be available for public review.
G. Porous pavement, green roofs, and capture and reuse systems shall be allowed for the purpose of achieving the volume control requirements of §
208-161A.
H. Where conditions warrant on development sites with streams, post-construction
monitoring may be required by the Township Engineer to demonstrate
compliance with the stormwater management provisions of this article.
For sites that comply with §
208-161A, the following uses are permitted when authorized as a conditional use pursuant to §
208-117, provided that the applicant demonstrates to the reasonable satisfaction of the Board of Supervisors, following a review and submission of a recommendation or comments by the Planning Commission to the Board of Supervisors for its consideration, that the authorization will provide public stormwater improvements as required in this article.
A. For portions of the tract where the underlying zoning district is
nonresidential:
(1)
Any use permitted in the underlying district.
(2)
Accessory restaurant uses within a permitted office building
or medical office building, provided the uses are clearly incidental
and subordinate to the primary office use and do not exceed 10% of
the gross floor area of the building or 10,000 square feet, whichever
is less. If outdoor consumption of food is proposed, it shall meet
all of the following requirements:
(a)
Outdoor seating must be contiguous to the establishment preparing
the food being served and shall not extend beyond the limits of the
frontage.
(b)
If any outdoor seating extends into any public right-of-way,
an unobstructed walkway at least six feet wide shall be maintained
for pedestrian circulation.
(3)
For parcels that abut expressways, as identified in the Tredyffrin Township Comprehensive Plan of 2009, Table 2.7.1, Roadway Functional Classification, as amended, or for parcels that abut one-way expressway access roads as defined in §
208-164B, hotels, including such accessory uses as recreation facilities for use only by registered hotel guests, restaurants, lounges, meeting rooms and other common areas;
(4)
Structured parking facilities designed to serve the uses on the site. Such parking facilities need not meet the requirements of §
208-103C(1),
(2) and
(3).
B. For portions of the tract where the underlying zoning district is
residential:
(1)
Any use permitted in the underlying zoning district.
(2)
Age-targeted housing in the form of single-family detached,
single-family semidetached (twins) and single-family attached (townhouses).
C. For any portion of the tract:
(1)
public stormwater improvements required by this section.
(2)
Accessory uses as permitted in §
208-12G, subject to the requirements thereof, provided that in the TCS, such use may include storage within a completely enclosed building in conjunction with a permitted use.
(3)
Signs when erected and maintained in accordance with the provisions of Article
XXV and the signage requirements of the underlying zoning district.
For sites that comply with §
208-161A, every building or use shall comply with the following requirements, in addition to the requirements of §
208-117 for conditional use approval. In the case of a group or combination of buildings erected on a lot or lots in accordance with a unified plan, the group as a unit shall comply.
A. Tract setback requirements.
(1)
Nonresidential buildings and structures must be set back from
any property line a distance of at least 50 feet or a distance at
least equal to the height of the building, whichever is greater.
(2)
Residential buildings must be set back at least 50 feet from
any property line.
B. Building and impervious coverage.
(1)
The coverage ratios of the underlying zoning district shall
apply. However, when a contiguous property covers more than one nonresidential
underlying zoning district, the applicant may determine permitted
impervious and building coverage on a tract-wide basis by combining
the allowable building and impervious coverage ratios of the underlying
nonresidential zoning districts.
(2)
For the purpose of calculating allowable building and impervious
coverage, areas with public stormwater improvements may be included
in lot area.
(3)
For single-family attached dwellings, 200 square feet of additional
impervious coverage per dwelling unit for residential decks, patios
or other outside paving shall be planned for and accommodated in the
initial stormwater management system and may be added after the initial
occupancy of the home.
C. Nonresidential zoning districts.
(1)
Height.
(a)
The by-right height permitted in the underlying zoning district
may be increased by one story (not to exceed 14 feet).
(b)
The height of any parking structure shall not exceed 75% of
the height of the tallest principal building on the subject property.
(2)
Buffer. Along each existing property line which directly abuts a residential district or use, a buffer area of not less than 20 feet in width shall be provided, subject to the provisions of §
208-102B. The buffer area may be within any required yard or setback.
D. Residential zoning districts.
(1)
Density. Density may be increased up to 2.3 times the rate permitted
in the underlying zoning district. The rate permitted in the underlying
zoning district shall be demonstrated through the submission of a
by-right plan that complies with the requirements of that underlying
zoning district.
(2)
Building size and placement. No unit shall be less than 24 feet
in width. A minimum building separation distance of at least 10 feet
for single-family semidetached dwelling units (twins) and at least
20 feet for all other buildings shall be provided. No more than six
units may be attached in any single building.
(3)
Height. The height of any residential building or structure
shall not exceed 35 feet, except that the height of any single-family
attached building or structure shall not exceed 45 feet if the units
are set back at least 75 feet from any existing property line shared
by a residential district or use.
(4)
Buffer. Along each tract property line adjacent to an existing residential use or district, a buffer area of not less than 20 feet in width shall be provided, subject to the provisions of §
208-102B. The Board of Supervisors may reduce this requirement if it is determined that a buffer of less than 20 feet in width will provide adequate protection to an abutting property or district, or if the public stormwater improvement is located within the buffer area.
E. Special development regulations. Notwithstanding the provisions of §
181-3 (Interpretation) of Chapter
181, Subdivision and Land Development, due to the public stormwater improvements required in this overlay district, the requirements of §
181-51 (Recreational facilities and open space land) of Chapter
181, Subdivision and Land Development, shall not apply.
F. Parking. The parking regulations of §
208-103 shall apply, with the following exceptions.
(1)
Office.
(a)
There shall be at least one parking space for each 250 square
feet of gross floor area or fraction thereof.
(b)
Shared parking is permitted subject to the following requirements:
[1]
Provide a parking demand analysis for each use that exceeds
2,400 square feet of gross floor area for approval by the Township
Engineer that demonstrates adequate parking will be provided for the
uses on site during peak hours. The analysis should generally be consistent
with the published recommendations of the Institute of Traffic Engineers
(ITE). Data collected from similar or comparable uses to the proposed
use also may be submitted for review. For any change of use involving
shared parking, a new parking demand analysis shall be submitted as
determined necessary by the Zoning Officer.
[2]
Demonstrate that the shared parking shall be located no further
than 500 feet from the entrance to the buildings and uses they are
intended to serve.
[3]
Provide a written, legally binding agreement among the owners
of record, their tenants and those with which parking facilities are
shared for review and approval by the Township.
(2)
The required parking spaces shall be a minimum of nine feet
wide and a minimum of 18 feet in length. On-street parallel parking
spaces shall be a minimum of seven feet wide and a minimum of 22 feet
in length.
(3)
Off-street surface parking for nonresidential uses may be located in any required yard, except that such parking areas shall not be located closer than 50 feet to any street line for office uses. The area between such parking areas and street lines may be used for sidewalks and landscaping, as required by Chapter
181, Subdivision and Land Development.
Sites that comply with §
208-161A may be eligible for the following incentives, in addition to the incentives in §§
208-162 and
208-163 above. To be eligible, the public stormwater improvements must meet the requirements of §
208-161A(3), and exceed the baseline peak rate control requirements in Chapter
174, Stormwater Management, by 50% for all design storms (calculated before the application of any of the exemptions set forth in Chapter
174), in addition to the requirements of §
208-117 for conditional use approval. In the case of a group or combination of buildings erected on a lot or lots in accordance with a unified plan, the group as a unit shall comply.
A. Residential uses. Density may be increased up to 4.5 times the rate permitted in the underlying zoning district, provided the public stormwater improvements meet the requirements of §
208-161A(3), and exceed the baseline peak rate control requirements in Chapter
174, Stormwater Management, by 50% for all design storms. The rate permitted in the underlying zoning district shall be demonstrated through the submission of a by-right plan that complies with the requirements of that underlying zoning district.
B. Height for nonresidential buildings. For parcels that abut expressways, as identified in the Tredyffrin Township Comprehensive Plan of 2009, Table 2.7.1, Roadway Functional Classification, as amended, or for parcels that abut one-way expressway access roads, the by-right building height may be increased by two stories (not to exceed 28 feet for the two stories). For purposes of this Subsection
B, the term "expressway access road" shall be defined as any one-way road with direct access to or from an on-ramp or an off-ramp for an expressway. Properties will be deemed to abut an expressway if the property abuts the expressway or would abut the expressway but for the intervention of a public right-of-way including, without limitation, a walking trail or an abandoned railway.
C. Building and impervious coverage.
(1)
Impervious coverage may be increased up to the limits provided in Subsection
C(1)(a) or
(b) below, provided at least two times the amount of additional impervious cover sought is converted to porous paving that complies with current stormwater management requirements. A secondary, conventional inlet/piping system or other drainage element will be required to ensure transmission of surface water into the underground storage and infiltration bed. An operations and maintenance plan for long-term maintenance of the porous paving system also will be required to be submitted and approved by the Township Engineer, and recorded along with the stormwater management plan at the Chester County Recorder of Deeds.
(a)
For nonresidential uses, impervious coverage may be increased up to 10% above the by-right limit if the conditions in §
208-164C(1) are met.
(b)
For residential uses, impervious coverage may be increased up to 5% above the by-right limit if the conditions in §
208-164C(1) are met.
(2)
If a green roof is included on any building, a credit of 50% of the area of the green roof will be applied to the calculation of impervious coverage; provided, however, that the foregoing credit shall have no effect on the calculation of impervious area pursuant to meeting the requirements of Chapter
174 or the requirements for public stormwater improvements in this article.
(3)
Building coverage requirements in the underlying district shall
not apply.