What is zoning? Enforcement   Local Zoning - Zones mapped in Bronx Community District 8 Table of local zoning districts   The Special Natural Area District Summary of requirements                                                                                                                        What is zoning? Zoning text and maps Zoning laws consist of two parts: text which spells out specific regulations for each zoning district (R1, R3-2, C1, etc.) and maps that show where each district applies.  The text and maps are available on line at the Department of City Planning web site, www.nyc.gov/planning.  (In the blue area at the right of their home page, click on zoning, then choose either zoning text or zoning maps.) Zoning shapes how the city looks and functions The shape and function of New York City is guided by zoning. The first zoning laws in New York City were adopted in 1916.  The new regulations brought stability and predictability to the Manhattan real estate market, where commercial and manufacturing development was surging into established residential neighborhoods in lower Manhattan and new technologies allowed taller buildings that blocked the light and air of their neighbors.  Rather than a hodgepodge of incompatible uses, the new zoning encouraged development that was in line with existing development.  Today, the City’s zoning manages a complex, fine-grained landscape ranging from skyscrapers to suburban neighborhoods, within an equally complex set of community and city-wide needs.   How does zoning work?  Zoning districts define land use, building height and bulk, population density, parking requirements, open space, and other physical aspects of development.  Each zoning district defines a particular set of parameters. Zoning districts define land uses according to whether they are residential, commercial, or industrial (R, C, or M (manufacturing) districts).  They lay out formulas for determining the allowable heights and sizes of buildings, the required space between buildings, and how much parking is required. They set out minimum lot sizes, the number of housing units that may be built per acre, and how much open space must be retained.                                                                                                 Zoning articulates a vision The zoning that is applied to an area reflects the values and preferences of residents and leaders for the direction of development in their neighborhood, their borough, and their city. As conditions and needs change, zoning must be revisited. Publications such as the Mayor’s Strategic Policy Statement for the City, the Bronx Borough President’s Strategic Policy Statement for The Bronx, and the New York City Waterfront Revitalization Program periodically reexamine needs, policies and strategies.  The City or community may then propose zoning changes to reflect evolving conditions. Community land use plans recommend appropriate neighborhood zoning Like several other communities in the city, Bronx Community District 8 created a land use plan to guide development of our neighborhoods over the next 10 to 20 years.  The plan, titled CD 8 2000: A River to Reservoir Preservation Strategy, was approved by the City Council in 2003.  It takes a detailed look at our community and recommends ways to meet specific needs and achieve community goals. Zoning changes are one of the tools the plan recommends for meeting land use goals.  Since the Plan's adoption, the Department of City Planning has acted on these zoning recommendations.  Approved rezonings are noted in the table below, in the section on local zoning.  Continuing rezoning activity is described on the Department of City Planning website. For a summary of all of the plan's recommendations, visit our planning page.      Old zoning, new buildings ... are they what we expect?                                                               At times, individual lots or whole neighborhoods are not built out to the maximum building size or type allowed by zoning.  For example, zoning may allow garden apartments and two family homes, but a neighborhood may develop with single-family homes instead. Zoning regulations define maximums, such as in building height and floor area, and minimums, such as in lot size and yard size. Development is not required to build to the limits, just to stay within allowable ranges. As community character becomes established, residents may forget about or be unaware of the unused development potential. When a lot is then fully built out, it can be a discordant element in the design of the neighborhood. It is in response to these situations that the city created many of its contextual zoning districts and has approved many recent rezonings. Contextual districts increase the focus on neighborhood characteristics Certain zoning districts are called contextual districts, because they aim to guide the appearance of new development so that it fits into the visual context of the existing neighborhood.  To do this, contextual districts require that new development include specific design elements, such as, for example, peaked roofs where they are common.                                                                                                                           Review, approval, and enforcement of zoning:  the Departments of City Planning and Buildings TO REPORT SUSPECTED VIOLATIONS OF ZONING REGULATIONS, CALL 311.  BE PREPARED TO PROVIDE THE ADDRESS OR BLOCK AND LOT OF THE PROPERTY IN QUESTION. Zoning districts are designed and mapped by the Department of City Planning (DCP). Creation of a new zoning district, revisions of existing zoning text, or changes to the zoning map require review by community boards, the borough president, and the city planning commission, with ultimate approval by the city council. Enforcement of the zoning code is the responsibility of the Department of Buildings (DOB).  In most cases, the DOB reviews projects for compliance with zoning (as well as compliance with the building code and construction regulations) and approves the project "as of right", meaning that no review by City Planning is necessary.  Application for a building permit is made directly to the DOB.  In some cases, zoning districts require review and approval by the DCP before the DOB can issue a building permit. Application is made to the DCP for a certification, authorization, or special permit, depending on the nature of the work.  For more information on these applications, see the Department of City Planning web site.  Once a project is complete, the Department of Buildings inspects the work to be sure it complies with the approved plans, and ultimately issues a Certificate of Occupancy.                                                                                                 Local Zoning - Zones mapped in Bronx Community District 8 History New York City's first zoning regulations, adopted in 1916, allowed high-density development in many parts of the city—including sections of the outer boroughs where the prevailing development was low-density.  Much of Riverdale was zoned to allow apartment houses in what was then either open space or low-density neighborhoods. In the 1950s, community activists responded to a wave of apartment house development making its way north from the newly-opened Henry Hudson Bridge by working with the Department of City planning to develop a vision of Riverdale's future:  The apartment houses would follow the top of the ridge along Riverdale Avenue.  They would be balanced by a wide ribbon of single-family, detached homes and the existing institutions on the slopes between the ridge and the River.  There would be a gradual transition from single-family to high rise areas, and commercial development would be concentrated in areas where the traffic it generated would not infringe on residential streets. This planning effort was so thorough that the resulting zoning changes still define large parts of Riverdale today.  (To read a short history of this planning effort, see our archived newsletters: Riverdale's Roots, part 1, and Riverdale's Roots, part 2.) Today's challenges In 2003, the City Council approved Community Board 8's newest land use plan:  CD 8 2000: A River to Reservoir Preservation Strategy.  The new plan looks at today's needs in the District, and makes it clear that preservation of neighborhood character is an overriding concern.  Thirteen areas are recommended for rezoning.  To see a summary of all of the Plan's recommendations, click here. Current Zoning in CD 8                                                                                The table below lists all zoning districts currently mapped in Bronx CD 8.  Actual regulations are much more extensive; this table is meant only to give a broad idea of the types of development envisioned for each zoning district.                                                                                                                       Zoning Districts Currently Mapped in Bronx Community District 8 * District Land uses Selected distinguishing characteristics and functions.  (For full regulations, see zoning text) Rezoning title & date approved by the City Council;  Links to City Planning Dept. descriptions R 1-1 lowest density residential zone in the city; single-family detached only minimum lot width: 100 ft.; minimum lot size: 9,500 square feet Riverdale-on- Hudson 11/11/05 R 1-2 single-family detached residences only minimum lot width: 60 feet; minimum lot size: 5,700 square feet   R 2 single-family detached residences minimum lot width: 40 feet; minimum lot size: 3,800 square feet   R 3-1 single- and two-family residences, detached or semi-detached minimum lot width for detached: 40 feet; for semi-detached: 18 feet North Riverdale 12/7/04 R 3A contextual residential district; single- and two-family residences, detached only allows much narrower lot width for detached than R3-1: 25 feet;  lowest density district to allow zero-lot-line buildings North Riverdale 12/7/04   R 4 allows multiple dwellings such as garden apartments and row houses     R 4A contextual residential district; single- and two-family residences, detached only   Van Cortlandt Village 9/28/04 R 5 allows same housing types as R4 but at higher density often used as transition between lower- and higher-density areas   R 6 medium-density housing typically between 3 and 12 stories tall   R 6A contextual residential district; allows more lot coverage than R 6, but typically lower heights.  typically 6 stories Central Riverdale and Spuyten Duyvil 9/28/04 Van Cortlandt Village 9/28/04   R 7-1 medium-density residential typically 14 stories   R 7A greater lot coverage and lower height and setback requirements than R 7. typically bulky 6- to 8-story residential buildings Central Riverdale and Spuyten Duyvil 9/28/04   C 1-2; C 1-3 commercial district; accommodates the retail and personal service shops needed in residential districts typical uses are intended to serve the daily needs of the immediate neighborhood   C 2-1; C 2-2 C 2 districts permit a wider range of local retail and service establishments than C 1 districts intended for businesses that cannot be supported solely by the immediate neighborhood   C 8-1; C 8-2 automotive and other heavy commercial services bridge between commercial and manufacturing districts   M 1-1; M 1-2 light manufacturing; must meet strict noise, air pollution, and other nuisance-creating activity levels located adjacent to low-density residential districts   SNAD Special Natural  Area District overlay intended to preserve unique natural characteristics of an area text revised 2/2/05 * Sources:  on-line DCP zoning maps and DCP's Zoning Handbook, 1990, (available from the Department of City Planning bookstore).

The Special Natural Area District (SNAD)

Special Zoning Districts for special purposes

In New York City, special purpose districts are mapped to respond to very specific conditions in particular areas of the city.  The special purpose districts are one way to fine-tune zoning in a city as large and diverse as ours.

What you need to know:

The Special Natural Area District (SNAD) in Riverdale is labeled NA-2 on the zoning map and is shaded in grey.  There are three other SNADs in New York City—two on Staten Island and one in Queens. 

It is the property owner's responsibility to become familiar with the regulations under SNAD.  Of primary importance, the owner should know to call the Bronx Office of City Planning, at 718-220-8500, to discuss requirements under SNAD for any construction or modification projects he or she is contemplating. 

The SNAD is known as an overlay zone.  It is overlain on top of a base residential zoning.  The regulations of the SNAD supplement or modify the regulations of the base zoning.  Section 105-02 of the zoning text states that "except as modified by the express provisions of this Chapter, the regulations of the underlying district remain in effect." 

All projects in the SNAD must begin with an informational meeting with the Department of City Planning.  Call the Department at 718-220-8500 with a description of your property, the natural features on it, and the project you have in mind.

Projects that do not require a permit from the Department of Buildings may still need to be reviewed by the Department of City Planning, if natural features will be affected.  You should call City Planning even if you do not need a permit from Buildings.

Projects that require a permit from Buildings may be approved by City Planning under a simple "certification" process, if they meet strict guidelines.  City Planning will evaluate whether your project falls into this category, or will work with you to modify your proposal to move it into this category.

SNAD Regulations

The following overview of the SNAD regulations is provided here for informational purposes only—the actual regulations are much more complex than this overview.  To ensure that you comply with all zoning requirements, you must contact the Bronx Office of City Planning, at 718-220-8500, with your specific project plans and a description of your property.  City Planning will guide you through the approval and permitting process.  ("Sect." refers to a section of the zoning regulations.)

Natural features that are protected under SNAD include, but are not limited to: (Sect. 105-11)

• trees 6" caliper or greater,
• topographic elements:  steep slopes (incline of 25% or greater), existing natural topography (0 % to < 25 % slope), and topsoil,
• rock outcrops and erratic boulders,

• wetlands and surface water features, and
• botanic environments.

Trees:

Healthy trees of 6" caliper or greater are protected under SNAD. 

**Note:  a tree of 6" caliper or greater that is dead, diseased, or imminently hazardous to property or persons may be removed without special review.  When removing such a tree, you must obtain a letter from a certified arborist documenting the tree's condition and justifying its removal.

Healthy trees of 6" caliper or more may be removed only if (Sect. 105-31, a-d):

• The tree is located in areas to be occupied by your development project, or it is within a distance of 15 feet from the exterior walls of a building,
• The continued presence of the tree would create special hazards or dangers to persons or property,
• the tree will interfere with the growth or health of another tree that is designated for preservation, or
• An authorization has been granted by the City Planning Commission approving its removal.

The Department of City Planning will advise you of the number of trees you must plant to replace those you remove. 

Topography (including steep slopes):                                             

Existing topography is protected by building and grading restrictions that relate to the steepness of the property.  Modifications to a slope can affect stormwater and groundwater drainage patterns, soil conditions, and vegetation health. 

In the SNAD, lots are characterized as:

Tier I - average slopes of < 10 %

Tier II - average slopes of 10 % or greater (includes "steep slopes")

steep slopes - slopes of 25 % or greater

Building Restrictions (Lot Coverage)

The portion of a zoning lot which, when viewed from above, is covered by a building or portion of a building, is called "Coverage". 

Grading Restrictions

For any project that does not require a permit from the Department of Buildings, such as some swimming pools, a garden shed, or a fence, you may not alter the existing topography by more than two feet without review from City Planning. (Sect. 105-021, b) (This applies only to properties containing a residential building as of 2/2/05.)

On Tier I sites, if your project requires a building permit, any modification of existing topography requires an authorization from the City Planning Commission (Sect. 105-421).

On Tier II sites, for any project requiring a building permit, you must receive authorization from the City Planning Commission for any grading beyond 15 feet of the location of a building foundation (with the exception of driveways and private roads).  Grading within 15 feet of a foundation is subject to regulations in Sect. 105-34, which defines specifics for cut and fill slopes, compaction of fill, retaining walls, and other grading elements.  Driveways and private roads are regulated under Sect. 105-35. 

Topsoil:                                                                                       

Topsoil is protected from erosion during construction.  Sect. 105-36, (f) states that "Any exposed earth shall have straw, jute matting , or geotextiles placed on it within two days of exposure and be seeded with annual rye grass during construction."  Sect. 105 -37 requires that a development on a Tier II site, that needs an authorization, must install one of the following erosion and sedimentation control measures:  benches and berms, diversion channels, debris or sediment basins, retention ponds, or grassed waterways or outlets.   

Rock Outcrops and erratic boulders:

An outcrop is a piece of bedrock exposed at the surface.  An erratic boulder is a boulder that originated elsewhere and was carried and deposited at its current location by water or ice (in our area generally by glacier ice).

The geology of Riverdale is displayed in its outcrops and boulders.  These are of interest to scholars and residents, and are protected from modification as follows:

Erratic boulders of less than 6 feet in diameter may be moved.  Erratic boulders "with a diameter at any point of 6 feet or more" may only be moved by authorization of the City Planning Commission. (Sect. 105-423)

Modification or alteration of a rock outcrop must always be authorized by the City Planning Commission. (Sect. 105-424)

Wetlands and surface water features:

Modification of a wetland or surface water feature must always be authorized by the City Planning Commission. (Sect. 105-426)

Botanic environments:

Botanic environments are assemblages of plants adapted to specific environmental conditions.  They are characterized as primary succession communities, secondary succession communities, climax communities, dune or heathland, and wild grasslands.  They consist of varying proportions of ground cover, shrubs, small trees, and large trees.

Botanic environments, where they exist, are part of the defining characteristics of the SNAD and are to be protected or replanted under SNAD regulations.  Replanting is to reproduce the plant assemblages that are removed, or another assemblage determined characteristic of the area.  Replanting is to reproduce the entire ecosystem, including but not limited to ground covers, annuals, perennials, herbs, vines, and woody plants, and with consideration of the fauna that is dependent on the plants.

More Information                                                                          

For a slightly more technical treatment of SNAD regulations, see our FAQs on the SNAD.  The Preservancy prepared these FAQs after the zoning regulations were revised in spring of 2005.

Full SNAD regulations are found in Article X, Chapter 5 of the zoning resolution.  (There are actually many special overlay zoning districts in the City's zoning code, each addressing a specific need or area.  They are contained in Articles VIII through XII.)

For clarification of regulations, or to begin the project permitting and approval process, call the Bronx Office of City Planning, at 718-220-8500.