Whenever there is a discrepancy between minimum standards or dimensions noted herein and those contained in Chapter
197, Zoning, or Chapter
70, Building Code or other official regulations of the City of Lewes, the highest standard shall apply.
All subdivisions and site developments shall conform to design standards that will encourage good development patterns within the City of Lewes. The subdivision and site developments plans shall be such as to lend themselves to the harmonious development of the City and enhance the public welfare in accordance with §
170-2. Purpose and the design standards in this chapter, compatibility with abutting developed or undeveloped lands, as well as the City's Comprehensive Plan, including but not limited to the City's core values. The subdivision and site developments plans shall conform with all City regulations and ordinances, and applicable state and federal laws and regulations. In addition, the subdivision plans shall conform with the following standards and considerations:
A. Site design. Intent: Ensure that the arrangement of lots and structures
is consistent with development patterns (existing or planned) and
the proposed buildings and site improvements employ context-sensitive
designs that help protect neighborhood character, property values,
and maintain core values as stated in the Comprehensive Plan.
(1) Lot configurations.
(a)
Standards.
[1]
Site design elements shall display a clear and unified organization
of building, landscaping and circulation, elements that support the
functions of the site. Site plans shall effectively demonstrate how
the elements of the site relate to the street front and provide for
compatibility with adjacent uses.
[2]
Each lot shall have frontage on and access to a street.
[3]
All single family attached and detached residential dwellings
shall be oriented to the street.
[4]
Front facades shall squarely face the street and should not
be set at an angle unless existing adjacent homes are sited at an
offset angle.
[5]
Buildings may be oriented to common open space areas, provided
that street frontages are developed consistent with guidelines on
facades facing streets.
[6]
Perimeter residences that are part of new developments shall
be oriented to existing streets, minimizing the extent of sound walls
or rear yard walls, except where necessary due to acoustical requirements.
Exceptions include homes that abut primary roads, as defined in the
City Comprehensive Plan, in which case a parallel road can be used
or perimeter structures can face an internal road as long as the facade
facing the primary road contains facade and roof treatments typically
used on a front elevation as opposed to rear sidings. Applicants shall
consult Historic Lewes Byways representatives to obtain guidance on
design recommendations for structures along a specific byway corridor.
[7]
Where applicable, blocks shall:
[a] Not exceed 1,200 feet in length;
[b] Be sufficient to allow two tiers of lots; and
[c] For wider blocks (as per zoning) set aside area
for utility or service access.
(b)
Guidelines.
[1]
The developer should take a creative approach to the use of
the land and related physical development, as well as utilizing innovative
techniques to enhance the visual character of the development.
[2]
Avoid excessive lot depth in relation to width.
[3]
Developments should interconnect with the existing neighborhoods
adjacent to them. Traffic calming measures such as curb extensions
and bulb-outs can be considered where proposed streets connect to
existing neighborhoods.
[4]
Flexibility in design to take the greatest advantage of native
landscapes, existing community character and layout, trees and other
native vegetation as well as other unique features.
[5]
Designs should avoid separation resulting from high, solid fencing
and walls, or blank walls of buildings.
[6]
Encourage development that contributes to the character of Lewes
by establishing linkages to community focal points, such as open space,
parks, schools, and civic buildings.
[7]
Projects should provide for future connections to currently
undeveloped properties via public or private streets, internal drives
and biking and walking trails.
[8]
Designs should be sensitive to and compatible with historic
and architecturally significant buildings in the vicinity and should
enhance important community gateways and view corridors.
[9]
Side walls of townhouses or multifamily buildings should be
designed with front facade elements, such as windows and doors, to
avoid blank walls facing the street.
[10] Large, flat facades should be avoided by articulating
the building mass to create substantial shadows and visual interest.
Windows, dormers, projected entrances, and overhangs are encouraged
on the street facing facade to add variety and maintain a pedestrian-scale.
[11] Strengthen the pedestrian realm by encouraging
landscaping and building elements, such as enhanced paving materials,
accent lighting, streetscape furniture and adequate sidewalk space,
which will contribute to pedestrian environments that are attractive
and physically safe.
(2) Structures and site improvements.
(a)
Standards.
[1]
Buildings and structures shall have a mix of styles, sizes,
facades, roof pitches and color. For all subdivisions where the developer
is proposing either a package of style of houses or land-home packages,
the developer must submit with both the preliminary and final plans
an artist rendition or a computer-generated illustration of the exterior
of the proposed structure(s) for every model or style proposed.
[2]
Placement of buildings shall consider the existing context of
the surrounding area. New and infill residential development shall
respect privacy and solar access through appropriate siting of structures.
[3]
Attached garages that face the street shall be set back at least
five feet from the front facade.
[4]
Detached garages shall be consistent with the architectural
style of the house. Window styles, exterior materials, and trim detailing
shall have a similar appearance to the house (but use of exact materials
shall not be required).
(b)
Guidelines.
[1]
Buildings and structures (architectural styles) and site improvements
should be designed to reflect Lewes's historic and marine community.
[2]
Buildings should be oriented to maximize public and pedestrian
interaction along adjacent street corridors, except for areas defined
as primary streets in the City Comprehensive Plan (consult Historic
Scenic Byway Management Plan for specific guidelines.
[3]
Facade components facing the street should correspond to the
scale of the human form. This is accomplished by visually breaking
up facades into smaller components with elements such as front porches,
stoops with overhangs, windows, wall insets, balconies, ledges and
trim and by stepping back upper stories.
[4]
Residential entries should be separated from the street by semi-private
transition areas, with one of the following characteristics:
[a] Porches, terraces, stoops or canopy-covered doorways
close to or attached to sidewalks should be raised above street grade
at least two feet; or
[b] A private entryway setback and separated from the
sidewalk with a gate, fence, wall or other method.
[5]
Incorporate complete streets guidelines to create a safe, pedestrian-friendly environment, including:
[a] Accessible sidewalks and shared-use paths;
[c] Crosswalks with clear pavement markings.
[d] Streetscape amenities (bicycle and pedestrian infrastructure,
transit shelters, public places, trails, parks and recreation facilities
and street furniture).
[e] Bicycle lanes or shoulders (five to six feet wide).
[f] Pavement markings and signage.
[6]
Scale, proportions, and height should be compatible with the
general characteristics of homes in the surrounding neighborhood.
For example, effort should be made to reduce the appearance of mass
of a larger two-story house constructed among smaller or single-story
dwellings. The following methods may be incorporated to reduce the
apparent mass of a dwelling:
[a] Step back portions of the home. For example, set
the second story back from the first story or add an enclosed porch
on the first story.
[b] Use dormers to break up roof mass, if consistent
with the architectural style of the home.
[c] Incorporate horizontal design detailing to visually
break up flat walls. Examples include wide skirt boards, mid-section
trim between stories, frieze boards along roof eaves, partial or complete
gable returns, or a change in siding or masonry patterns or materials.
[7]
Roof form, pitch, and scale should match the architectural style
of the structure. Simple gabled and hipped roof forms are preferred.
Mansard and flat roofs should be used only if appropriate for the
architectural style of the structure. Eaves that extend a sufficient
distance to create shadow lines are encouraged if appropriate for
the architecture of the structure. The roof of the garage and other
accessory structures should mimic the roof of the structure in both
form and pitch.
[8]
Increase privacy on adjoining properties by employing the following
techniques:
[a] Locating/reorienting direction of windows or decks
to minimize views directly into adjoining structures and outdoor gathering
places.
[b] Use structural features (e.g., raised planter boxes
on parapet walls, nontransparent glazing) to restrict view angles
to long rather than short distance view.
[c] Use smaller upper floor windows or use selective
glazing at privacy sensitive locations.
[d] Use landscaping to reduce potential privacy impacts.
[e] If possible, increase setbacks for living areas
that require more privacy. Where necessary to achieve greater privacy,
re-orient the directions of windows or decks or adjust window size
or sill height (e.g., use transom windows, skylights, or other alternative
glazing).
[9]
Detached or rear-loaded garages are recommended.
[10] Street-facing doors on attached garages should
incorporate glass panel windows.
[11] The use of individual bay doors (single stall)
is preferred over double-wide doors, particularly for street-facing
attached garages.
B. Site suitability.
(1) Intent: The proposed land use and its design can occur without increasing
danger to health or peril from fire, flood, or other hazards. The
proposed land use and design also addresses long-term sustainability
needs (environmental, economic, social) to ensure it can occur without
increasing hazards, supports community needs and avoids significant
long-term costs or maintenance demands.
(a)
Standards.
[1]
Preliminary design shall identify existing site conditions such
as natural grade, wetlands, floodplain, tree clusters, hedgerows or
vegetated buffers, water protection areas, scenic views, historic
or cultural resources on the site and immediately adjacent. Lot layout
and building placement shall be designed to minimize impacts to these
existing conditions.
(b)
Guidelines.
[1]
Building and site layout should be compatible with existing
topography and vegetation. Preservation of existing trees, particularly
older growth trees, is recommended.
[2]
Project elements (lots, buildings, access drives, parking, walkways,
and service areas) should be located to protect, enhance, or minimize
impacts to natural and cultural site features. For example, development
proposals should be designed to enhance scenic view sheds, protect
established landscaping, and preserve any historic or cultural resource
areas.
[3]
Site design should provide for the efficient use of the land
so that expenses for development, future maintenance and community
services are manageable. The efficient use of the land that may result
in the reduction of development and future maintenance costs of street
and utility systems is highly encouraged.
[4]
To help maintain community character parking areas should be
located to the rear of buildings to minimize their visibility from
the street. The coverage of driveways and parking areas in the front
and exterior side yards should be minimized to the greatest extent
possible.
[5]
Critical natural features that provide nature-based services
(filter runoff, reduce flooding, buffer winds), support biological
diversity, or maintain local character should be preserved as undeveloped
common open space or required yard areas along with conservation measures
to ensure they are permanently preserved.
C. Lighting requirements. Intent: Lighting guidelines are intended to
eliminate adverse impacts of light spillover; provide attractive lighting
fixtures and layout patterns that contribute to a unified exterior
lighting design; encourage energy efficiency, and provide exterior
lighting that promotes safe vehicular, pedestrian and bicycle access
to and within a development, while minimizing impacts on adjacent
properties and the nighttime sky.
(1) Applicability.
(a)
Lighting standards contained in this chapter apply to all major
subdivision or site plans (site plans reviewed by Planning Commission
only) developed or redeveloped after the amendment adoption date.
The standards apply to all proposed uses and structures where there
is interior or exterior lighting.
[Amended 7-10-2023]
(b)
Uses or structures developed prior to adoption of these lighting
standards maintained as nonconforming structures, as defined by the
City Zoning Ordinance, will not be required to comply with the lighting
standards applicable to new subdivisions or land developments.
(c)
Provisions of this section do not apply to:
[1]
Emergency lighting or lighting used for public road construction
projects.
[2]
Temporary seasonal lighting displays.
[3]
Temporary events (regulated by Chapter
80, Community Events).
[4]
Lighting on existing uses (not included in a site plan review).
(2) Standards (all uses).
(a)
Standards established by the City of Lewes and/or Lewes Board
of Public Works or DelDOT (where applicable) for lighting systems
design, installation, and maintenance shall be used in all applications
those agencies administer or review.
(b)
Illumination levels. Lighting, where required by this chapter,
or otherwise required or allowed by the City, shall have illuminances,
uniformities, and glare control in accordance with the latest edition
of the IES Lighting Handbook or current Recommended Practices of the
Illuminating Engineering Society of North America (IES).
(c)
Luminaire (fixture) design.
[1]
Luminaires shall be of a type and design appropriate to the
lighting application and shall be aesthetically acceptable to the
City.
[2]
For the lighting of predominantly horizontal surfaces such as,
but not limited to parking areas, roadways, vehicular and pedestrian
passage areas, merchandising and storage areas, automotive service
areas, loading docks, culs-de-sac, active and passive recreational
areas, building/site entrances, and bicycle and pedestrian paths,
luminaires shall:
[c] Meet full cutoff/fully shielded criteria (using
IES standards).
[3]
For the lighting of predominantly nonhorizontal applications
or surfaces such as, but not limited to, facades, landscaping, signs,
billboards, fountains, displays and statuary, when their use is specifically
permitted by the City, luminaires shall be:
[b] Installed and aimed so as to not project their
output offsite, past the object being illuminated, skyward or onto
a public roadway.
Low light fixtures [not exceeding 500 lumens (output of a standard
40-watt incandescent lamp)], are exempt from the requirements of this
subsection.
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[4]
LED light sources shall have a correlated color temperature
that does not exceed 3000K in industrial and commercial districts,
and not exceeding 2700K in residential districts.
(d)
Lighting control.
[1]
Vegetation screens shall not be employed to serve as the primary
means for controlling glare. Rather, glare control shall be achieved
primarily using such means as full cutoff/fully shielded luminaires,
shields and baffles, and appropriate application of luminaire mounting
height, wattage, aiming angle and luminaire placement.
(e)
Residential development lighting.
[1]
Streetlighting.
[a] Streetlights shall be of a consistent style and
be aesthetically pleasing throughout the subdivision or site development
and should add value to the community as well as being compatible
with the style of the homes in the subdivision.
[2]
Parking spaces.
[a] In multifamily developments, common parking areas
of four spaces or greater shall be illuminated.
[b] In residential developments with lots of less than
10,000 square feet, where four or more common contiguous parking spaces
are proposed, such spaces shall be illuminated.
(3) Guidelines.
(a)
Use energy efficient street as well as signage lighting which
can meet design standards while minimizing energy use and resources
(maintenance).
(b)
Residential developments, streetlighting should be provided
at:
[1]
The intersection of public roads with entrance roads to the
proposed development;
[2]
Intersections involving proposed public or non-public major-thoroughfare
roads within the proposed development;
[3]
At the far end of cul-de-sac bulbs;
[4]
Terminal ends of center median islands having concrete structure
curbing, trees and/or other fixed objects not having breakaway design
for speeds of 25 mph or greater;
[5]
Defined pedestrian crossings located within the development;
[6]
At other locations along the street as deemed necessary by the
City.
(c)
Special consideration should be given to minimizing adverse
impact of a proposed lighting plan on beach and sensitive habitat
areas, including but not limited to the following:
[1]
For properties that are adjacent to beach areas, avoid the installation
of lighting fixtures that are directly visible from the beach and
adjacent nesting areas. Where possible place lighting fixtures so
they are beneath an adjacent dune ridge thereby shielding it from
adjacent beach areas. Lighting fixtures should also be placed to avoid
illumination of dune areas unless absolutely needed and can be extinguished
when not needed.
[2]
For properties within or immediately adjacent to areas designated
in the Delaware Ecological Network as "core areas, non-core hub areas,
or corridors", lighting plans shall be developed that either a) limit
any artificial lighting (0.0 luminaires) into the defined areas or
b) incorporates mitigation strategies into the lighting plan that
includes an identification of the species of greatest conservation
need in that habitat area and use of lighting systems that limit disruption
to those habitat areas.
D. Landscaping requirements. Intent. Maintain and use landscaping to
enhance the aesthetic value and appearance of the area, to help preserve
residential communities, and to maintain and enhance natural resources
to maintain benefits associated with a healthy ecosystem while avoiding
costs related to weather extremes, habitat/biodiversity loss, or increased
runoff/flooding.
(1) Applicability. The landscaping standards of this section shall apply
to any proposed major subdivisions or site developments as described
below:
(a)
The requirements and standards prescribed herein shall be the
minimum for all plans as required by this section. Standards established
by other City ordinances or by state and federal rules and regulations
shall apply where those standards are more restrictive than the standards
set forth herein. All required landscaping shall be install prior
to issuance of a certificate of occupancy permits. It shall be the
responsibility of the owner to maintain all landscaping in accordance
with the standards of this chapter.
(b)
An overall landscape plan consistent with this section, Chapter
177, Trees, and all other applicable City ordinances, prepared by a registered landscape architect, shall be submitted.
(c)
The City may also require an overall landscape plan in other
instances as deemed appropriate.
(d)
In cases where preserved natural features existing on the site replicate or essentially replicate the planting requirements of this section, a request for waiver for some or all of these requirements may be sought in accordance with §
170-7 Modifications. waivers and varying requirements. Invasive plants on the site cannot be used to comply with landscaping provisions and should be removed as part of the site improvement process.
(2) Standards.
(a)
Consistent with the landscape plan requirements described below,
the applicant shall plant trees and shrubs and make other landscape
improvements, e.g., berms and fences, as necessary to negate the adverse
visual impacts that the applicant's proposed actions may have on the
development, adjoining properties, adjacent roadways, and the City
in general.
(b)
The applicant shall follow the planting and landscape design
guidelines set forth below:
[1]
The landscape standards included in this section are minimum
requirements. The City reserves the right to require that these standards
be exceeded if conditions so warrant.
[2]
Landscape plans with perennial elements with a focus of using
native and non-invasive species shall be used to enhance the survival
rate of the plantings to support the native ecosystem.
[3]
Plant material size and spacing standards. All plant material
shall be native or non-invasive species and shall be of good nursery stock, not subject to disease
or blight. Nursery-grown plant material shall conform to those listed
in the "American Standard for Nursery Stock," ANSIZ60.1, current edition,
published by the American Nursery and Landscape Association (ANLA).
The following guidelines are the minimum required for all nursery-grown
plant materials or transplanted trees as required in this section:
[a] Unless otherwise allowed for specific reasons,
all trees shall have comparatively straight trunks, well-developed
leaders and tops, and root characteristics of the species or variety
showing evidence of proper nursery pruning.
[b] All plants must be free of insects, mechanical
injuries and other objectionable features at the time of planting.
Plant material shall be installed in accordance with accepted planting
practices.
[c] Street trees shall comply with Chapter
177, Trees. Not less than 60% of the trees to be planted shall be species native to the region. Multiple-trunked trees shall be identified as such in the plant list and shall be counted as one tree. The City may consider a smaller number of larger caliper trees to meet planting requirements, provided the monetary values are equivalent.
[d] Ornamental and flowering trees shall have a minimum
height of eight feet at installation. Multiple-trunked trees shall
be identified as such in the plant list. Multiple-trunked trees shall
be counted as one tree.
[e] Evergreen trees shall have a minimum height of
seven feet at installation.
[f] Shrubs shall comply with the following requirements:
[i] Large shrubs shall be not less than three feet
tall at planting. A minimum of 50% of the shrubs shall be native to
the region.
[ii] Small shrubs shall be not less than 24 inches
tall or 18 inches in spread, depending on variety, at planting. A
minimum of 50% of the plants shall be native to the region.
[g] Shrubs shall be spaced according to their size,
growth characteristics, and intended use.
[h] Ground cover shrubs, herbaceous perennials, bulbs,
and annuals shall be spaced appropriate to type and size at installation.
Ground covers shall be spaced so that 100% of the beds are covered
after two years' growth.
[i] A variety of plant species are encouraged to avoid
monocultures, to encourage long-lived species, and to promote wildlife
habitat.
[j] Other plant types, such as those marginally hardy
to the area or those which have an unusual form, and/or nonvegetative
features, such as water or rock gardens, may be incorporated into
required planting areas. However, only those plants within the feature,
which meet the above requirements, may be counted toward satisfying
the minimum planting and buffering requirements of this section.
[k] To allow for design flexibility, plant material
substitutions from the requirements may be permitted at the discretion
of the City. In such cases, the applicant must demonstrate to the
satisfaction of the City that the general intent of the ordinances
is achieved and that the substitutions represent an equivalent monetary
value to the required landscaping.
[4]
To prevent soil erosion, suitable ground cover shall be provided
on all areas of the project that are not covered by paving, stone,
or other solid material. Ground cover may consist of shrubs, spreading
plants, sods, and decorative grasses.
[5]
When the proposed landscape improvements do not conform to these
guidelines, the applicant shall undertake other design measures, e.g.,
site planning, architectural, landscape architectural, which in the
opinion of the City, achieve comparable results or that render the
guidelines unnecessary or inappropriate.
[6]
At every street intersection there shall be a clear view between
the heights of three feet and 10 feet in a triangle formed by the
corner and points on the curb 30 feet from the intersection and entranceway.
(c)
Applicants proposing a major subdivision or site plan abutting
a designated Historic Lewes Byway shall:
[1]
Consult with Historic Lewes Byways representatives to obtain
guidance on proposed landscape plan designs.
[2]
Prepare a vegetation and view shed evaluation as part of the
landscape plan identifying the following:
[a] Location, type and size of all existing trees or
tree stands with an emphasis on native trees, and a notation of whether
each such tree or tree stand is to be preserved, replaced or removed;
and
[b] An assessment of defined (within City plans) or
identified scenic viewsheds.
(d)
Applicants proposing to subdivide or develop a property that
contains waterways or wetlands shall obtain a letter from the City
Hazard Mitigation and Planning Team identifying any concerns with
invasive plant conditions and a recommended management plan to manage
conditions as part of the development proposal.
(e)
Trees along streets. Trees shall be planted in accordance with Chapter
177 along both sides of proposed public and or shall be planted along both sides of or private streets. Trees shall also be planted in proposed boulevard islands, islands in the center of culs-de-sac, and adjacent to sidewalks on streets without parkways. Where an existing street transecting a development is deficient in trees, sufficient trees shall be planted along both street-sides and boulevard abutting the development to bring the street into conformity with these requirements. The design of utility facilities shall accommodate the planting of trees along streets.
(f)
Buffering and screening. Landscaped buffers and screening, where
applicable, shall be designed to serve identified purposes such as
providing effective transitions between different use types, preserving
resources or privacy, mitigating impacts (noise or glare) or obscuring
views of utility services or parking lots. In its review of proposed
development the City shall balance the need to buffer or screen areas,
using defined standards, with the core values to maintain the human
scale and intimate neighborhood character that defines quality of
life.
[1]
Residential area buffers as defined below shall be provided
as follows:
[a] Residential area buffers shall be provided along
a shared property line in the following instances:
[i] Proposed residential dwellings on smaller lots
or consisting of attached units are located within 100 feet of a shared
property line with existing detached dwellings.
[ii] Proposed nonresidential development adjacent to
residential dwellings located in a zoning district which permit attached
or detached dwellings.
[b] Residential area buffers shall provide a minimum
thirty-foot vegetated buffer and shall be included in open space and
shall not be located on individual lots meeting one of the following
standards:
[i] A planting strip within the required thirty-foot
buffer consisting of a mix of canopy trees, understory trees, and
shrubs to provide a functional screen between the developments.
[ii] A landscaped rolling berm at least four feet in
height within the required thirty-foot buffer.
[iii] A solid fence or wall designed with durable materials,
texture and colors compatible with the adjacent residential development.
The fence or wall will be set back at least five feet from the shared
property line, with suitable landscaping on both sides.
[2]
Corridor buffers. For proposed developments along a marked state
road or designated Historic Lewes Byway (New Road, Pilottown Road/Front
Street, Savannah Road, Kings, Highway, Gills Neck Road, and Cape Henlopen
Drive) buffer areas and screening shall be provided. The following
shall be used to create a visual corridor buffer:
[a] Buffer width: between the right-of-way and applicable
property lines:
[i] Where there are no established individual lots,
a fifty-foot buffer is required, measured from the applicable road
right-of-way to the near face of the adjacent structure; or
[ii] Where individual lots are established, a fifty-foot
buffer is required, measured from the applicable road right-of-way
to the near property line; or
[iii] Where there is a street between the structure
and the corridor (state road) a fifty-foot buffer is required, measured
from the applicable road right-of-way to the near edge of the street.
[b] Buffer treatments. Within the required buffer,
the following are permitted to provide screening from the roadway
and can be no closer to the right-of-way than 25 feet:
[i] A planting strip within the required buffer, consisting
of a mix of canopy trees, understory trees and shrubs to provide a
functional screen; or
[ii] A landscaped rolling berm at least four feet in
height within the required buffer; or
[iii] A solid fence or wall designed with durable materials,
texture and colors compatible with the adjacent residential development.
The fence or wall will be suitably landscaped on both sides.
[3]
Agricultural buffer. A forested buffer area, designed and maintained in accordance landscaping standards of this section, and Chapter
177, Trees, of the Code of the City of Lewes, with a minimum width of 30 feet shall be provided for lots abutting an agricultural area.
[4]
Wetlands buffer. A vegetated buffer area in accordance with §
197-74G of the City Zoning Code.
[5]
Site element screens shall be placed to screen identified element
to the satisfaction of the City, when such elements are proposed within
50 feet of a property or right-of-way line. Site element screens may
be located within required buffer areas. Screen plantings used around
parking lots shall be placed to provide a snow stockpile area. Site
element screens may be eliminated if they are adjacent to or within
other buffers, when the screen buffer effectively screens views of
the site element. Site element screens shall comply with the following
planting requirements:
[a] Site element screens shall be one of the following
types, according to use. If a use is not listed, the screen most suited
to the use shall be used.
[i] Low screens shall be used around the perimeters
of all parking lots or other similar vehicular use areas, including
service stations, sales lots for motorized vehicles, vehicular stacking
lanes associated with a drive-through, and around trash enclosures
or storage buildings when decorative walls, such as brick, latticework
or split-face concrete block, are proposed.
[ii] High screens shall be used adjacent to loading
areas, around trash enclosures and storage buildings, when fencing
or plain concrete masonry units are proposed, and around transformers,
maintaining the required clear distance. High screens or six-foot-high
opaque fencing shall also be required to buffer accessory structures
from the higher classification street on reverse frontage lots.
[iii] Yard screens shall be placed around vehicular
storage areas that are not used as parking lots or sales areas, around
the perimeter of tank farms and similar facilities, and around utility
towers and equipment yards.
[6]
Buffer and screen requirements.
[a] No structures may be placed within the buffer area
and no manufacturing or processing activity or storage of materials
shall be permitted, except for the following:
[i] Landscaped treatments such as berms, fences, or
walls which aid in screening and do not conflict with the character
of adjoining properties, or block clear sight distance required at
intersections.
[ii] Structures relating to and used for landscaping
such as: tree wells, tree guards, tree grates and retaining walls
to preserve stands or specimens of existing trees or used for other
functional purposes.
[iii] Site element screens, existing natural features,
structural garden elements (such as gazebos and trellises), water
features, sculpture, and project identification signs may be placed
within the buffer, provided they do not replace or diminish the intended
screening effect of the buffer.
[iv] Roads which provide direct ingress/egress for
the tract or lot, including appurtenant structures within road rights-of-way
such as curbs, sidewalks, signs, lighting standards, or benches.
[v] Underground utilities. Existing plantings, woodlands,
hedgerows, topography, or man-made structures can reduce or eliminate
the buffering requirements if they partially or completely achieve
the same level of screening as the planting requirements outlined
in this section. This determination shall be made at the discretion
of City Council.
[b] Existing trees within the required buffer yard
greater than three inches in caliper or greater than 12 feet in height
shall be preserved to the extent feasible. Such trees may be counted
towards required plant materials as determined by City Council.
[c] Fences, walls and berms shall be used in conjunction
with required landscaping, not to replace it.
[d] If berms are proposed, they shall conform to the
following standards:
[i] Berms shall be a minimum of four feet in height
and shall not be steeper than three-foot horizontal distance to one-foot
vertical distance.
[ii] Berms should be located to work in conjunction
with vegetation, fences and/or natural features to provide an effective
buffer. They shall be laid out to replicate naturally occurring landforms.
Their locations shall not adversely affect stormwater management.
[e] The buffer planting shall be so placed that at
maturity vegetation extends not closer than three feet from any street
or right-of-way.
[f] The developer shall place boundary markers on the
edge of corridor, agricultural and wetlands buffers, at a spacing
of one marker per 100 feet of buffer boundary line to prevent buffer
encroachment. The boundary markers shall face away from the buffer
and must be placed on posts installed securely in the ground. Posts
can be metal or wood. If wood posts are used, they must be at least
four inches by four inches in size and made of treated wood. The posts
must extend a minimum of three feet above the ground surface and must
be sunk at least two feet below ground. The boundary markers shall
be four inches by six inches rectangular with black lettering and
azure blue background.
(g)
Parking lot design and landscaping. In addition to the off-street parking specifications in located in §
197-61, Off-street parking, of the zoning ordinance, the following planting and landscaping standards shall be applied for any major subdivision or site development:
[1]
All parking lots with five or more spaces shall be designed
and effectively landscaped with trees and shrubs to:
[a] Provide shade in order to reduce the amount of
reflected heat and to improve the aesthetics of parking lots.
[b] Reduce the visual impact of glare, headlights and
parking lot lighting.
[c] Facilitate pedestrian circulation and safety.
[d] Facilitate vehicular circulation by delineating
driving lanes and defining rows of parking.
[2]
Planting islands shall conform to the following standards:
[a] There shall be one planting island, a minimum of
nine feet wide by 18 feet long, spaced not more than 135 feet apart,
or every 15 parking stalls, in single or double bays.
[b] Islands shall be placed opposite each other in
adjacent rows of parking, to reduce the number of islands, and to
increase the area available for tree roots.
[c] The last parking stall in a row shall be separated
from drive aisles by a planting island a minimum of nine feet in width.
[d] Each planting island shall contain one shade tree
plus shrubs, ground cover, perennials and/or mulch to cover the entire
area at maturity. At least 50% of the proposed shade trees shall be
native to the region. Shrubs shall not exceed three feet in height.
[3]
Divider strips shall be provided on parking lots accommodating
90 or more parking spaces and shall conform to the following standards:
[a] Divider strips shall be placed every other bay
of parking, running the length of the rows of parking and landscaped
with plantings of shade, ornamental, and/or flowering trees, plus
shrubs, ground cover, and/or mulch to cover the entire area at maturity.
A bay of parking is the width of pavement needed to accommodate either
one or two rows of parking stalls, plus one access lane.
[b] Divider strips shall be a minimum of 10 feet wide,
unless a sidewalk is proposed within and parallel with the divider
strip. If a sidewalk is proposed within the strip, the divider strip
shall be increased in width by the width of the sidewalk to accommodate
the sidewalk.
[c] One shade tree shall be required for each 50 feet
of divider strip.
[d] Divider strips may be designed as rain gardens
or may be planted with combinations of shrubs and ground covers. Shrubs
near the ends of divider strips shall not exceed two feet in height,
so as not to block visibility. This shall not preclude the use of
taller shrubs elsewhere within the divider strip.
[4]
Plantings shall be placed between parking lots and buildings
to break up long stretches of facade and provide a more comfortable
pedestrian environment, according to the following standards:
[a] Plantings are required for all sides of a building
facing parking areas exclusive of building entrances. Plantings are
not required along the sides of buildings containing service or loading
areas. If part of a side of the building faces parking, only that
portion is subject to these requirements.
[b] The minimum planting requirement shall be one shade
tree per 50 feet of building facade plus five small shrubs per 50
feet of building facade. In lieu of shrubs, 50 herbaceous perennial
plantings may be provided per 50 feet of building facade.
[c] Any plantings in accordance with or in addition
to the requirements of this section may be placed in a lawn area,
tree pits, planters or hanging baskets as appropriate to the character
of the development, using the following guidelines as to placement:
[i] Tree placement shall take into consideration location
and size at maturity, including hazards with storm events. Applicants
shall work with Parks and Recreation during plan review to evaluate
any placement issues.
[ii] If any tree is located closer than 10 feet to
a sidewalk, approved root barriers shall be placed along the tree
side of the sidewalk for a distance of 12 feet, centered on the trunk.
[iii] The bottoms of hanging baskets shall be at least
eight feet above the sidewalk surface to provide for pedestrian clearance
and clear visibility.
[5]
Shrubs, ground covers and perennials used below shade trees
within parking lots shall be of species able to withstand the harsh
microclimate of a parking lot. Plant selection should take into consideration
tree growth and canopy cover, and should be partially shade tolerant
species.
[6]
To prevent conflicts with the opening and closing of automobile
doors and to reduce damage from automobile overhang, all shrub plantings
in parking lot islands and divider strips located adjacent to or abutting
parking stalls shall be set back such that there is a minimum of two-feet
from the curb or edge of pavement when the shrub reaches maturity.
[7]
Plantings required within the parking areas are exclusive of
other planting requirements such as street trees and buffers.
[8]
Plantings shall comply with the standards prescribed in §
170-26D(2) and the guarantee prescribed in §
170-26D(2)(i), except that dead material in hanging baskets, pots and urns shall be replaced promptly. If owner receives notification from the City replacement shall be made within defined time frame.
(h)
Landscape plans, prepared by a Delaware registered landscape
architect, shall be submitted at the time of preliminary and final
plan applications. They shall be on the same size sheets and at the
same scale as other corresponding layout plans in the set. They shall
contain all applicable general plan information indicated for preliminary
and final plans, respectively. They shall also conform to the following
additional standards:
[1]
Detailed planting areas, which are not clearly legible on plans
at a smaller scale, shall be shown at a scale of one-inch equals not
more than 30 feet to depict the detail. This may be necessary to communicate
plantings around signage, project entries, in courtyards, tot lots,
or building foundations, for example.
[2]
Cross section elevations shall be used to illustrate corridor
buffer areas in relation to street corridors and adjacent proposed
structures.
[3]
Existing and proposed improvements, including grading, utilities,
lighting, signage, stormwater management system structures, pavement
materials, water features, fences, and walls shall be shown and noted
on the landscape plans.
[4]
The outlines of ground cover and mulch beds shall be depicted.
All ground plane treatments shall be labeled, including grass.
[5]
The plans shall contain a plant list on the same sheet or reference
the sheet on which it appears. The plant list shall include the following:
[a] A key or symbol reference corresponding to labels
or symbols on the plan.
[b] The proposed quantity of each plant species.
[c] The scientific and common plant names, including
named cultivars, if applicable.
[d] The size of the plant at installation, according
to the American Nursery and Landscape Association (ANLA) standards,
which shall include height, spread, and caliper.
[g] Natural or maintained height and spread anticipated
after 30 years' growth.
[h] Any special specification or instructions, such
as full to ground, multi-stemmed, hedge, limb up to 12 feet, espalier,
etc.
[6]
The plans shall contain standard specifications for installation,
including a guarantee note and planting distances from utilities.
[7]
Details for landscape installation shall be provided, including
any specialty features, either on the same sheet or references to
the sheet on which they appear.
[8]
The signature and seal of the Delaware registered landscape
architect preparing the plans shall be provided.
[9]
A cost estimate of the proposed plantings shall be submitted
with the final plan application.
(i)
Installation, guarantee and maintenance. All landscape materials,
including existing and transplanted vegetation or materials depicted
on the approved landscape plan to satisfy the requirements of this
section, shall be financially secured, guaranteed, and maintained,
including, without limitation, compliance with the following:
[1]
All landscape improvements to be provided shall be installed
and maintained by accepted practices as recognized by the American
Association of Nurserymen. Planting and maintenance of vegetation
shall include, as appropriate, but not necessarily limited to, provisions
for surface mulch, staking and guying, irrigation, fertilization,
insect and disease control, pruning, mulching, weeding, and watering.
[2]
The applicant shall make arrangements acceptable to the City
that all landscape improvements installed in accordance with this
section shall be guaranteed and maintained in a healthy condition,
or otherwise be replaced by equivalent improvements, for a period
of 24 months following their installation, except as may otherwise
be required by this section.
[3]
After installation and prior to commencement of the guarantee
period required above, the City shall perform an inspection of the
finished site for compliance with the approved landscape plan. Following
this inspection, an as-built landscape plan shall be furnished to
the City by the applicant. Provided the finished site is found to
be in compliance, the twenty-four-month guarantee period shall commence
five days from the date of inspection. All plants shall be in a vigorous
and thriving condition at the end of the twenty-four-month period
as determined above. Final inspection of the site following the twenty-four-month
period will be made by the City.
[4]
The developer shall replace all dead trees and shrubs that are
part of the area's landscape design prior to transferring management
responsibilities to a homeowner association or equivalent.
[5]
Plants found to be in poor health or lacking normal growth habit
during the twenty-four-month guarantee period shall be replaced with
nursery-grown plants, in accordance with the approved landscape plan,
within 30 days of being notified by the City. If notification is made
out of season, replacements shall be made during the next planting
season. If the original plants declined due to poor species selection,
substitute plants, determined by the City to be more suitable for
the site's environmental conditions or planting scheme, shall be used.
A modified landscape plan shall be filed with the City. Replacement
plants shall be inspected by the City after installation.
[6]
The applicant shall be required to post financial security in accordance with §
170-21 of this chapter for all proposed landscaping required by this section, for existing plants being disturbed by construction activities, and for transplanted and preserved plants that are being used to satisfy the minimum requirements contained in this section or Chapter
177. The amount of the financial security shall be equal to 150% of the amount of the cost estimate for said landscaping as agreed to by the City and shall be based upon the cost of replacement with nursery-grown stock.
[7]
The applicant shall make arrangements acceptable to the City
for the property's long-term landscape maintenance. The applicant
shall provide the names, addresses, and telephone numbers of those
persons or organizations who will be assuming such responsibilities.
Landscape improvements required by this section shall be the subject
of suitable restrictive covenants and, if practicable, rules and regulations
governing the use and maintenance of common land and facilities, which
covenants, rules, and regulations shall be in form and substance acceptable
to the City Solicitor and, in the case of covenants, recorded as encumbrances
running with the land on which the improvements are installed. The
covenants, rules, and regulations shall, without limiting the foregoing,
require the maintenance and replacement and prohibit the destruction
or removal of all landscape materials and improvements depicted on
the approved landscape plan, empower the City to enforce said obligations,
and prohibit the amendment or termination of any of the mandatory
terms thereof without the express joiner of the City.
(3) Guidelines.
(a)
Applicants should present long-range landscape projections and
plans at the initial phases of development for approval by the City.
These plans should consider the desirability of planting a proportional
distribution of mature native trees. Protection of existing trees,
hedgerows and natural cover strips should be encouraged. The City
Parks and Recreation Commission may assist the developer in these
evaluations.
E. Open space requirements. Intent. Provide open space, in conjunction
with new development, to allow inhabitants to enjoy natural settings
and recreational activities, preserve and enhance unique and sensitive
natural or cultural resources, build upon and enhance the community
open space network and provide adequate transitions to better integrate
development into established communities or environmental areas.
(1) Applicability. The open space standards of this section shall apply
to any proposed major subdivision or site development as described
below:
(a)
Open space shall be provided within all major subdivisions and
site developments (applications requiring review by the Joint Site
Development Ad Hoc Review Committee). Open spaces are typically maintained
as common open space areas consisting of but not limited to lawns,
trees, landscaping, sidewalks or pathways and benches.
(b)
The requirements and standards prescribed herein shall be the
minimum for all plans as required by this section. Standards established
by other City ordinances or by state and federal rules and regulations
shall apply where those standards are more restrictive than the standards
set forth herein. It shall be the responsibility of the owner to maintain
all open space in accordance with the standards of this chapter.
(2) Standards.
(a)
Open space areas shall not comprise less than 20% of the gross area of a major subdivision or applicable site development. Additional open space shall be required in conjunction with residential multifamily, planned community, or cluster lot options in defined Annexation Zones - see Chapter
197, Table 7 in the City of Lewes Code for required open space.
(b)
Open space shall be configured so that:
[1]
At least 40% of the open space will be contiguous.
[2]
At least 20% shall be suitable for community open space which
is easily accessible to all units, without interfering with adjacent
dwelling units, parking, driveways and roads.
[3]
At least 60% will be usable open space outside of wetlands (tidal
or non-tidal) or floodways.
[4]
No more than 20% can be impervious.
(c)
No structures or uses shall be permitted to count as required
open space, except those that contribute to the passive or active
recreational use and enjoyment of the space such as play structures,
pergolas, picnic tables and benches.
[1]
Specific uses that cannot count towards open space include,
but are not limited to:
[b] Sewage or water treatment facilities.
[c] Storm water management basins, spillways, level
spreaders, bio-retention areas, and water retention ponds.
[2]
For projects that provide more than 30% of the gross area for
open space, and would utilize green technology stormwater best management
practices that can be graded into the natural terrain permitting recreational
use, the Planning Commission may recommend relief from this provision,
which may be granted at the discretion of City Council.
(d)
Open space areas shall be arranged where possible to interconnect
with adjacent open space areas, greenways, or byways to ensure the
potential for a contiguous open space network throughout the City.
If the development is adjacent to a public trail, park, greenway or
other preserved open space, an open access area must be provided to
ensure access by residents.
(e)
The size and location and configuration of open space shall
provide adequate access to residents within the subdivision or development
and enable appropriate access for maintenance. Long, thin (less than
10 feet in width or 20 feet in length - unless segments of an approved
trail or greenway connection) or inaccessible areas of open space
shall not count as required open space.
(f)
Open spaces shall be permanently protected from development.
All open space may be open to the residents within the development
or be dedicated to the City upon mutual agreement between the developer
and the City.
(g)
Ownership and maintenance of required open space shall be designated
through one of the following options - in order of preference:
[1]
Ownership in common by a homeowners' or community association.
The developer/owner/association shall provide for the development
and maintenance of any required open space in accordance with requirements
and specifications in the Delaware Uniform Common Interest Ownership
Act Title 25, Chapter 81, where applicable, or in accordance with
City standards for ownership and maintenance for open space areas
not otherwise covered by federal or state law.
[2]
For developments containing required open space for which a
homeowners' or community association is deemed not feasible by City
Council, open space areas shall be protected through conservation
easement which has been reviewed and approved by City Council. Terms
of the conservation easement shall describe the on-going maintenance
responsibilities and actions should management issues arise with the
common property.
(3) Guidelines.
(a)
Due consideration should be given to the preservation of large
trees, natural groves, waterways, scenic points, historic spots, and
similar community assets. Resource to consider include those identified
as part of the Parks and Recreation Commission plan review and/or
features identified in Comprehensive Plan Mapping (historic resources
and open space, environmental features) along with resources and connections
identified in the Greenway Master Plan.
(b)
For residential and community developments consideration should
be given to creating a central community gathering place.
(c)
Open space should be suitably landscaped, either by retaining existing natural cover and wooded areas (green space) and/or by revegetating the space described in a landscaping plan that enhancing open space areas through plantings which are consistent with the purposes of this section and landscaping standards (§
170-26D).
F. Archaeological
review.
[Added 11-13-2023]
(1) Purpose: identify, evaluate, excavate, and preserve archaeological
resources located within the City of Lewes.
(2) Applicability: this applies to major subdivisions, minor subdivisions,
and site development plans that have a high probability of containing
archaeological resources.
(3) "Professional archaeologist": as defined by the Secretary of Interior
Standards and Guidelines for Archaeology and Historic Preservation
(36 CRF Part 61).
(4) An identification level survey report shall be required for any development
that requires a major subdivision review, minor subdivision review,
or site development plan as identified in applicability.
(a)
The identification level survey report as identified in the
"Archaeological Survey in Delaware, February 2015," or its successor
document shall be submitted with the submission of the preliminary
plan.
(b)
The identification level survey report shall be completed by
a professional archaeologist and in accordance with the most recent
"Archaeological Survey in Delaware, February 2015," or its successor
document. The Planning Commission and/or Mayor and City Council may
require additional review regarding specific items as identified in
the identification level survey.
(c)
If the identification level survey report determines that further
research should be performed on the site, an evaluation survey as
identified in the "Archaeological Survey in Delaware, February 2015,"
or its successor document shall be completed, and a copy of the final
report shall be submitted to the City of Lewes Planning Department
prior to final plan approval for review by the Mayor and City Council.
(d)
The applicant shall comply with all state and federal requirements
pertaining to archaeological items identified in the identification
level survey.
(5) Incidental discovery of archaeological sites.
(a)
If archaeological resources or indicators are unearthed or exposed
in the course of the project, the following shall occur.
[1]
The applicant shall stop work immediately.
[a] The Planning Department will determine when work
will resume based on consultation with a professional archaeologist
or state professional after consultation with the City Manager or
designee.
[2]
The applicant shall contact the Planning Department immediately.
[3]
The applicant shall contact the State Historic Preservation
Office or relevant entity to determine the significance of the unearthed
or exposed resource or indicator.
[a] The applicant shall work with the professional
archaeologist or state professional to determine the disposition and/or
curation of archaeological elements found.
(6) Violations.
(a)
Violations shall follow §
170-8 and fines shall be adequate to deter noncompliance.
Intent: To ensure that all proposed subdivisions and land developments effectively manage runoff to 1) prevent hazards and avoid property damage, 2) provide solutions that can be effectively managed by prospective owners and 3) maintain or enhance natural resource areas. Designs should minimize runoff to help achieve these objectives to the greatest degree possible, as prescribed in §
197-76 Drainage. Systems shall be used, when necessary, that satisfy the requirements outlined in §
197-77 Permanent stormwater management. All land disturbance proposals shall be processed in accordance with the State of Delaware Sediment and Stormwater Regulations (Delaware Regulations, Administrative Code, Title 7, Section 5101) and other related provisions as outlined under the City code that addresses runoff, grading, erosion and sediment control (§
197-78), flooding (§
197-73), Water resources protection (§
197-75) or other related impacts.
A. Applicability:
(1) Prior to commencing any land disturbing activity, a plan must be
submitted and approved in accordance with the State of Delaware Sediment
and Stormwater Regulations, where applicable. During all phases of
construction, the developer shall maintain all drainage facilities
and watercourses within any applicable subdivision or development.
After obtaining the necessary inspections and approvals, the developer's
maintenance responsibilities shall terminate in accordance with the
provisions of the state regulations and transfer in accordance with
an approved maintenance plan. Maintenance of completed and approved
drainage facilities shall be by a state agency, or, in the case of
community stormwater management facilities, the maintenance corporation
for that specific subdivision, or, in the case of individual lots,
by the lot owner.
B. Standards.
(1) Grading.
(a)
A general overall subdivision grading plan approval is required before a subdivision or land development plan is recommended for recordation. The lines and grades plan must conform with the latest version of the final plan. Grading plans must demonstrate compliance with relevant standards outlined in §
197-76, Drainage, as well as, grading standards for buildings, roads, driveways or other improvements described in this section or other City Code provisions. In addition, grading plans shall describe how the proposed actions will comply with City regulations on erosion and sediment control as defined in §
197-78.
(b)
Before granting a certificate of occupancy, the developer shall submit, for review and approval by the City Engineer, an individual lot grading plan and lot grading certificate as defined in §
170-6.
(c)
The City shall inspect final grading around a building for conformance
to requirements of this chapter. Changes to grading, or to a building
on a lot where a lines and grades plan has been approved, must be
submitted for review, and be approved by the City Engineer before
issuance of a certificate of occupancy.
(d)
The amount of cutting and/or filling required on site shall
be minimized to the maximum practical extent by:
[1]
Honoring natural drainage divides;
[2]
Placing streets and roads as close to existing grade as possible;
and
[3]
Performing land grading in a way that minimizes adverse impact
to existing vegetation.
(e)
For the protection of areas designated on the record land development
or subdivision plan to remain undisturbed, a minimum ten-foot-wide
buffer must be provided between any grading, sediment control practice,
and/or building and the area(s) designated to remain undisturbed.
(f)
Improvements to streams and watercourses shall be designed and
constructed to preserve and enhance the natural environment to the
maximum extent practical and be reviewed and approved by the appropriate
permitting agency. Permits and approvals must be submitted to the
City Engineer for dissemination to the City and BPW.
(g)
Where stockpiling is necessary to complete the earth work for
a project that is approved after the effective date of this chapter,
all stockpiles shall be located in open space. The required erosion
and sediment controls shall be placed around the stockpile immediately.
Temporary vegetative stabilization shall be completed within seven
days of the formation of the stockpile. For any period of inactivity
longer than 30 days, the stockpile shall be stabilized with permanent
vegetation and maintained in such a manner so that the stockpile is
mowable (maximum slope 3:1). Stockpiles shall be no taller than 20
feet at any point as measured from lowest toe of slope of any pile
to the tallest point on the stockpile.
(2) Sediment and stormwater management.
(a)
Sedimentation and erosion control and stormwater plans. Applicants
for proposals that require issuance of permits approving sedimentation
and erosion control and stormwater plans will be required to apply
for and obtain approval in accordance with the State of Delaware Sediment
and Stormwater Regulations. Prior to submitting major subdivision
or site development plans for preliminary approval, applicants shall
participate in a preapplication review with the Sussex Conservation
District (SCD) to discuss proposed stormwater management concepts.
For plans requiring review by State of Delaware Department of Natural
Resources and Environmental Control (DNREC) Sediment and Stormwater
Program, applicants should coordinate with appropriate staff. Verification
and any feedback from the preapplication meeting will be submitted
to the City. Permit approval must be obtained and submitted prior
to final subdivision or site plan approval by the City.
(b)
The following references apply to sediment and stormwater management
design, implementation, inspection, and review:
[1]
DNREC Sediment and Stormwater Regulations, as amended.
[2]
Delaware Sediment and Erosion Control Handbook for Development.
[3]
Delaware Stormwater Management Design Manual.
(3) Green technology stormwater best management practices (GTBMPs) -
Applicants shall utilize the most effective low impact stormwater
drainage practices to address stormwater conveyance and stormwater
management objectives, with a special emphasis on GTBMPs, where practical.
GTBMP (see Figure 170-30) are those practices that incorporate the
following:
(a)
Stormwater runoff management via surface water dispersion, volume
reduction and discharge at multiple points to:
[1]
Maximize infiltration potential. Applicants shall utilize the
natural capacity of the soils to capture and infiltrate runoff from
impervious surfaces.
[2]
Maximize filtration potential. Applicants shall utilize the
soil profile as well as existing and enhanced vegetation to improve
the quality of the stormwater runoff.
[3]
Maintain non-erosive velocities of stormwater runoff. Applicants
shall maintain post-development stormwater flow velocities to an intensity
that does not adversely impact natural resources specifically those
identified in Article IX of the City Zoning Code and as required by
the DNREC Sediment and Stormwater Regulations.
FIGURE 170-30
Green technology stormwater best management practices (GTBMPs)
|
---|
Type
|
System Examples
|
---|
Bioretention
|
Rain garden, tree box filters, streetscape bioretention, large
bioretention, raised planter box
|
Bioswale or vegetated swale
|
Bioswale
|
Infiltration
|
Infiltration trench or Infiltration basin
|
Permeable pavement
|
Permeable concrete pavers, grid pavement systems, pervious concrete,
porous asphalt
|
Impervious removal
|
Impervious surface removal
|
Rooftop disconnect
|
Rainwater harvest or discharge to rain garden or open space
area
|
Green roof
|
Green roof
|
Rainwater harvesting
|
Rain barrel or cisterns
|
Tree planting or afforestation
|
Tree planting
|
Conservation landscaping
|
Conservation landscaping
|
Filtration
|
Surface sand filter, underground sand filter, organic, nonstructural
filter, perimeter sand filter
|
(b)
Utilization of strategies that disconnect long reaches of stormwater
flowing over impervious areas, including:
[1]
Addition of landscaped corridors to receive runoff.
[2]
Grading longer hydraulic flow paths through pervious conveyance
facilities.
(c)
Implementation of GTBMP at the source of the contributing runoff
that mimic or improve the predevelopment hydrologic water balance
on the project site.
(d)
Utilization of other practices or techniques approved by the
City, SCD and DNREC - Sediment and Stormwater Program.
(e)
Actual designs and application of GTBMPs shall be in accordance
with Delaware Sediment and Stormwater Regulations and described in
the Delaware Post Construction Stormwater BMP Standards and Specifications
guide, as amended.
(4) Acceptability of proposed techniques. The following criteria must
be submitted in order to determine acceptability of the proposed techniques
for stormwater quality control:
(a)
An investigation regarding the feasibility of the preferred
practices, as set forth in the Delaware Sediment and Stormwater Regulations
and investigation review comments from the SCD or DNREC Sediment and
Stormwater Program, prior to considering other alternatives.
(b)
Submission of ample evidence of the non-feasibility of a preferred
practice as a justification for using an alternate practice. The evidence
must relate to the following conditions, at a minimum:
[1]
Soil types and characteristics, seasonally high-water table
elevation and anticipated type of pollutant loading.
[2]
Documentation from the developer and the SCD, or DNREC Sediment
and Stormwater Program, of a proposed practice's ability to meet the
efficiency standards, as set forth in the Delaware Sediment and Stormwater
Regulations.
(c)
If a conflict arises between this section and a state law, the
state law requirement shall prevail if it is more restrictive.
(5) Stormwater utility collection systems.
(a)
No subdivision will be approved until stormwater management
system requirements have been determined by the developer and approved
by the Board of Public Works. Consideration should be given for providing
future stormwater service to any or all potential lots created by
a possible subdivision in any preexisting approved subdivision before
any entire street rehabilitation occurs. Additionally, consideration
shall be given for providing future connection to the subdivision
stormwater collection system from either existing, or future, users
of the BPW stormwater collection system. No subdivision will be approved
unless connection with a public stormwater drain is assured. All stormwater
mains, manholes, catch basins, pipes and conduits, and stormwater
collection appurtenances, shall be installed before paving of the
road except with the express permission of the City. For a period
of five years after acceptance of streets by the City, no utility
mains, manholes, catch basins, and/or stormwater collection appurtenances,
shall be installed in any paved streets. Construction and details
of utilities are governed by appropriate sections of this chapter
and the BPW Standard Specifications and Details (current edition).
(b)
The installation of stormwater utility collection facilities
shall be governed by the following regulations:
[1]
Plans. The developer shall prepare detailed plans for the stormwater
system in strict accordance with provisions of this chapter and in
accordance with BPW Standard Specifications and Details (current edition).
The improvement construction plan must be approved by the BPW Engineer
before any work shall be started.
[2]
Installation procedure. The developer has the choice of two
methods of constructing lines:
[a] The developer performs work under contract or by
his own work crew. This work must be reviewed and approved by the
BPW Engineer in advance of installation, designed and installed per
the BPW Standard Specifications and Details (current edition) and
installed under BPW supervision. All lines must be tested according
to the Board of Public Works standards.
[b] The developer can request the Board of Public Works
to construct lines.
[i] The Board of Public Works will put work out on
contract and the developer will pay for installation costs plus engineering
services and administrative fees.
[ii] The work is performed by the Board of Public Works'
crews on a force-account basis. The developer will pay for cost of
materials, labor and engineering services, and administrative fees.
[3]
Testing.
[a] The developer's contractor shall furnish all labor,
tools, materials, water, and equipment, including mirrors, flashlights,
or other artificial lighting, subject to the approval of the BPW Engineer
for testing and/or replacement of pipe, in accordance with these specifications.
The developer's contractor shall perform all testing in the presence
of the BPW Engineer.
[b] Mirror testing: Upon completion of pipe laying
and backfilling, a mirror test to check for defects, or leakage, and
for horizontal or vertical misalignment shall be conducted. Mirror
testing shall consist of reflecting sunlight or artificial light via
mirrors through the completed section of pipeline, which, to be accepted,
shall be true and straight in horizontal and vertical alignment to
allow for the full passage of the reflected light.
[4]
Location. The location of stormwater collection piping, manholes,
catch basins, and appurtenances shall be approved by the Board of
Public Works. Stormwater collection piping and manholes shall not
be installed longitudinally under sidewalks and/or curbs.
[5]
Size. Stormwater collection piping in the City right-of-way
(ROW) or City/BPW easements shall be reinforced concrete pipe (RCP),
Class IV. Other pipe materials outside City ROWs or City/BPW easements
shall be reviewed and approved by the BPW Engineer and shall be designated
as the operation and maintenance responsibility of the developer,
property owners, or property owners association, in the development
agreement. All materials used for storm sewer mains and appurtenances
must be equal to or better than the minimum standards and specifications
established by the Board of Public Works for storm sewer construction
work. Also, stormwater collection piping shall have a minimum diameter
of 15 inches and a minimum flow velocity of three feet per second
based on the Manning Equation. Pipe diameter shall be determined by
the volume of runoff produced by the post-development storm having
a 4% annual probability of occurrence, or the twenty-five-year, twenty-four-hour
rainfall event. If any of the storm sewer drains become a portion
of the primary storm sewer system within the City, the BPW may require
that a larger main and/or a greater depth be required than is required
for the particular subdivision. In such case the additional expense
incurred by increasing the size and/or depth of the main will be assumed
by the BPW.
[6]
Casing pipe. The required size of stormwater collection casing
pipes must be equal to, or better than the BPW Standard Specifications
and Details (current edition) for sewer construction work and approved
by the BPW Engineer.
[7]
Minimum depth. The minimum depth of stormwater piping shall
be three feet six inches to the top of pipe.
[8]
Horizontal separation. Stormwater piping shall be installed
at least 10 feet horizontally from any existing or proposed water
mains. The distance shall be measured outside edge to outside edge.
[9]
Vertical separation. Stormwater piping crossing water mains
shall be installed to provide a minimum vertical distance of 18 inches
between the outside of the water main and outside of the stormwater
pipe. The crossing shall be installed such that the stormwater pipe
joints will be equidistant from the water main pipe joints.
[10] When it is impossible to obtain proper horizontal
and vertical separation as required above, concrete encasement shall
be required to be installed a minimum of five feet each side of the
crossing point on the lowest utility.
[11] Changes in direction. Special sections of radii
of 10 feet to 15 feet shall be constructed when abrupt changes are
made in alignment and shall be approved by the BPW Engineer.
[12] Manholes. Manholes shall not be more than 300
feet apart on sizes up to 24 inches and not more than 450 feet apart
on greater sizes. The minimum diameter of manholes shall be four feet.
When approved by the Board of Public Works, inlets may be substituted
for manholes.
[13] Stormwater runoff from any lot shall be spread
out over yards, and not concentrated, before discharging over a sidewalk
or potential sidewalk.
[14] In addition to the requirements of this section,
the stormwater utility collection system shall be in compliance with
the Stormwater Management Manual provided by the Sussex Conservation
District. The necessary permit must be obtained from them and acknowledged
by the Board of Public Works prior to any clearing, grubbing, etc.,
of the site.
C. Guidelines:
(1) Consideration shall be given to the use of sustainable construction
materials and installation methods. Materials shall be reviewed and
approved by the BPW Engineer and BPW.