[Ord. of 12-4-1991, § 20-71; Ord.
No. 2003.16, 2-4-2003]
All new streets shall be designed consistent with requirements
herein; and any reconstruction or relocation of existing streets shall
reflect the minimum requirements as far as may be practical. The City
Council, after review and recommendation of the committee responsible
for capital projects, may accept a street to be a public way which
does not meet the requirements of this article. The Council may waive
specific requirements of this article if it is in the best interest
of the public to do so, based upon the recommendations of the engineer.
Developers are cautioned to obtain such waivers in advance of Council
acceptance. In the case of a subdivision, the Council waiver must
be obtained prior to approval by the Planning Board.
For roads and driveways within Shoreland and Resource Protection Areas, additional design standards apply to these projects. See Article
XIV, Shoreland Zoning, Section 15-H, for requirements.
In cases where a roadway is to be constructed that will be offered
to the City for acceptance as a public way and where such roadway
will be used to provide access to successive phases of development,
the developer, upon request for acceptance of the roadway as a public
way, shall provide a performance guarantee (letter of credit, insurance
policy or cash account), as surety for repair of damage to final paving
and curbing, in an amount equaling the cost of final paving and curbing
times 150% times 5% per year inflation factor.
(1) The performance guarantee shall be for an initial term of five years
and shall be renewed as required. The performance guarantee shall
remain in effect until 75% of the lots in the successive phases served
by such a road receive occupancy permits. The Director of Public Works
with the assistance of the Engineering Department shall review the
condition of the roadway prior to the release of the performance guarantee
and will make the determination of the cost to repair any deficiencies.
The repair shall be done by the developer to the satisfaction of the
City prior to any release of the performance guarantee.
[Ord. of 12-4-1991, § 20-72; Ord.
No. 2003.16, 2-4-2003]
No street shall be designed with a right-of-way less than 50
feet in width. Greater width shall be provided to accommodate such
features as on-street parking or surface drainage facilities. The
land within the right-of-way of an approved public road shall not
be used to meet the area requirements of any lot obtaining its frontage
from the public road.
[Ord. of 12-4-1991, § 20-73; Ord.
No. 2003.16, 2-4-2003]
(a) Subsurface utility conduits shall be located so as to minimize conflicts
and interference with one another, both in the original construction
and in future maintenance. The standards of the department of engineering
shall be adhered to in design, and the Director shall condition all
street opening permits to promote those standards.
(b) Aboveground features shall be located as delineated herein, to provide
for a minimum of mutual interference. In general, traffic control
devices shall be located behind the curb within the esplanade; utility
poles, trees and other plantings may be within the esplanade or at
the rear of the sidewalk, provided they are not underneath any overhead
wires or over any subsurface conduits and do not block any line-of-sight
required elsewhere in this chapter. Hydrants shall be located to the
rear of the sidewalk unless circumstances demand an alternate location,
as determined by the Chief of the Fire Department, or his/her designee.
[Ord. of 12-4-1991, § 20-74; Ord.
No. 2003.16, 2-4-2003]
(a) Minimum angle. In general, right angle (ninety-degree) intersections
are preferred, but a variation of up to 15° either way may be
permitted.
(b) Curb radius. Intersecting curblines (or edge of pavement, if there
are no curbs) shall be cut back to a radius of not less than 25 feet
(9.0 m). The right-of-way line shall also be a radius of sufficient
length to assure no narrowing of the sidewalk and/or esplanade of
the narrower street.
(c) Separation of adjacent intersections. The intersection of a minor
street with any major street shall be separated from all other such
intersections by at least 200 feet (61 m) as measured along the center
line of the major street. This condition shall apply if the two successive
intersections are on the same side of the major road. For intersecting
streets on opposite sides of the major street, the intersections shall
be horizontally spaced either less than 25 feet apart or more than
200 feet apart. Horizontal projection shall be based on the distance
between the center lines of the intersecting roads with the major
road, starting from a point 100 feet back from the intersection with
the major road and drawing a line along the center line of the road
that intersects with the major roads center line. In all cases, it
is encouraged that the travel lane portion of the minor road entering
on to the major street should be at a 90° for a minimum of one
car length, or 20 feet.
(d) Block length. In subdivisions and other planned developments, the
street pattern shall be such that blocks shall be at least 600 feet
(180 m) long, but no more than 1,200 feet (360 m).
[Ord. of 12-4-1991, § 20-75; Ord.
No. 2003.16, 2-4-2003]
(a) All changes in direction of streets shall be accomplished by the use of appropriate curves, rather than by abrupt deflections. The degree of curvature shall be sufficient to ensure adequate sight distance for the design speed of the street, but in no case shall the road's center-line radius be less than those shown in
Table A, Section
62-126, except for corner radii at intersections and at culs-de-sac or other turnarounds.
(b) No two curves of reverse alignment shall be contiguous, but shall have a straight portion (i.e., tangent) of street interposed. The length of such tangents shall not be less than those values shown in
Table A, Section
62-126.
[Ord. of 12-4-1991, § 20-76; Ord.
No. 2003.16, 2-4-2003]
The design of streets shall provide for future continuation
of existing streets, and proper projection onto adjacent lands, so
as to provide for continuous, through streets upon ultimate development.
Every effort shall be made in the design stage to avoid alignments
which cannot be extended in the future.
(1) If a dead-end street is necessary, either permanently or temporarily,
a suitable turnaround shall be provided at the closed end. A turning
circle shall have an island in the center that is sized to allow two
full traffic lanes to encircle it. The minimum radius of such an island
shall be 65 feet, the outer pavement edge shall have a minimum radius
of 91 feet, and the right-of-way shall have a minimum radius of 105
feet. Any plantings or other objects within an island shall not restrict
visibility across the entire island.
(2) Turnaround: A hammerhead or "T" turnaround shall be constructed to
comply with the applicable standards of this section, and the perpendicular
cross piece of the "T" shall have the same width as its associated
road, and shall extend a minimum of 40 feet to either side of the
center line of the dead-end street. The cross piece of the "T" shall
be located within a fifty-foot wide right-of-way that shall extend
at least 20 feet beyond the ends of the pavement. No lot may be accessed
from either ends of a hammerhead or a "T" turnaround.
(3) Dead-end streets in the RF Zone only: A dead-end street shall not
exceed in length a distance of 1,500 feet, as measured along the proposed
street center line, from the end of the dead end road to the outside
edge of the traveled way of the nearest intersecting through road.
Exceptions to the maximum dead-end lengths:
a. If an applicant can demonstrate (through a master plan) that the
street will be connected to create a through street in future development,
the Planning Board may allow dead-end lengths to temporarily exceed
1,500 feet.
b. If a road loops back on to itself (i.e. lollipop or p-shaped), it
may exceed the standards above, provided that the point at which the
road loops back onto itself as measured from the beginning of the
dead-end road is not more than 1,500 feet.
(4) When a temporary turnaround of whatever design is provided, the plans
shall clearly indicate the limits of the easements for roadway purposes,
and the dimensions of those easements, so as to eliminate any uncertainties
at such time as the street shall be continued, as to which portion
of the easements, if any, are to revert to specific abutting properties.
[Ord. of 12-4-1991, § 20-77; Ord.
No. 2003.16, 2-4-2003]
Grades of all streets shall be held to a reasonable minimum,
but in no case less than 1% or greater than 8%. Additionally, within
75 feet of an intersection, the road grade shall be no greater than
3%.
Exception to the maximum road grade — For minor residential
roads only:
(1) Roads with slopes greater than 8% (up to a maximum of 14%) have to
increase the level off distance by 25 feet for each percent over 8%
coming into intersections.
[Ord. of 12-4-1991, § 20-78; Ord.
No. 2003.16, 2-4-2003]
The proper drainage of stormwater within the right-of-way of
any street is influenced by the following features: roadway crown,
gutters and curbs, culverts and ditches, catch basins and subsurface
storm drains; and all such features shall be designed to function
together to effect a smooth and efficient removal of stormwater from
the travel lanes of the street. In general, urban areas will be drained
by subsurface facilities, whereas surface drainage facilities usually
will be satisfactory in non-urban areas.
(1) Open drainage, where used, will be by trapezoidal ditches running approximately parallel to the roadway, together with culverts under the road at appropriate locations, and culverts under all driveways and side streets. Both culverts and ditches shall be designed to accommodate a twenty-five-year storm, using the Manning formula. Culvert ends shall be protected by masonry headwalls or other suitable method, and shall discharge into a riprap protected area with a plunge pool, or other approved method. Maximum culvert side slopes shall be 33% (1:3), and shall be stabilized with grass or any other method allowed in Section
62-132. Ultimate discharge shall be into a receiving body having ample capacity to accommodate the added volume of water.
(2) Subsurface drainage will be used on all streets having curbed gutters.
Catch basins or curb-inlets will be located at the uphill side of
any intersecting streets or as directed by the engineer; otherwise,
basins shall be placed at intervals so that a twenty-five-year storm
will not cause ponding greater than 50% of the total crown of the
roadway, nor velocities greater than 500 feet per minute in the gutters.
Pipes shall be no smaller than 12 inches in diameter, and shall have
a minimum of four feet (1.2 m) of cover over the crown of the pipe.
If conditions do not allow for the required four feet of earth cover,
a blanket of approved insulation material may be placed over the pipe
to compensate; the width of such insulation shall be equal to three
times the nominal pipe diameter. In no case shall the earth cover
be less than two feet.
(3) If the maximum water table is within 18 inches of the ground and
if ditches can not be used, an underdrain system shall be installed
and discharged in a positive manner to appropriate open or closed
system. A note shall be placed on the plan that if evidence of the
water table is discovered during the inspection process the engineer
may require underdrain to be installed. Follow underdrain specifications
in MDOT Standard Specifications for Highways and Bridges, most recent
edition.
(4) Stormwater management. In order to preserve nonurban natural resources
and keep construction costs down, the City of Biddeford will require
the developer to implement a stormwater management plan utilizing
low-impact water collection structures.
a. For roads servicing five or less lots or roads located within a cluster
subdivision, vegetative buffers and swales shall be utilized. However,
if there are extenuating circumstances that do not afford the use
of vegetative structures (land slope, wetland protection, neighboring
properties, etc.), and the applicant's engineer has proven that
there are no other reasonable alternatives, the engineer will work
with the applicant to determine the best means of stormwater management.
b. For roads serving greater than five lots, subsurface stormwater drainage
may be used, although if feasible, vegetative (surface) structures
should be incorporated.
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Refer to "Private Ways and Roads Standards (Section 51) in the
Performance Standards (Article VI) for details on vegetative drainage
systems under Stormwater Management for Subdivisions.
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[Ord. of 12-4-1991, § 20-79; Ord.
No. 2003.16, 2-4-2003]
The roadway portion of a street layout shall consist of those features which serve to support, channel or restrict the vehicles using the street. It includes the pavement and its base material, curbs, guardrails, medians, shoulders, access ramps and driveway aprons. (Note: See Section
62-126,
Table A, for minimum roadway construction standards.)
(1) Travel lanes: Lane width for City streets shall not be less than those values shown in Section
62-126,
Table A. The shoulders must be a minimum of two feet on each side. If a curb or berm is installed, the travel lane shall be a minimum of 13 feet in width.
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For minor residential streets in the RF Zone, the travel lane
width shall be a minimum of 10 feet with two-foot gravel shoulders
at each side and no curbing. If curbing is technically necessary,
as determined by the engineer, for a RF Zone minor residential street,
then the street must comply with the City street standards previously
stated.
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(2) Parking lanes: When provision is made for parallel parking along
the side of any street, the parking lane shall be at least 7 1/2
feet (2.3 m) in width. An eight-foot paved shoulder may be designated
and used for parking, consistent with other ordinances.
(3) Medians: If a median is desired to separate traffic lanes, it shall
be no less than four feet (1.22 m) in width (except for temporary
traffic dividers used during construction operations). If a median
is used to channelize traffic at intersections, it shall be no less
than one-foot wide. Medians may be raised above the travel surface,
in which case mountable edgings set no more than 45° from horizontal
shall be used, and the material behind the edging shall also be graded
to a slope no greater than 10% Depressed medians shall have paved
shoulders next to the travel lanes, paved and graded no steeper than
2% for at least four feet (1.22 m), and material within the median
to be graded no steeper than 10%. Medians may accommodate plantings,
drainage features, informational or directional signs, or other traffic
control devices provided they conform to the standards of the Manual
on Uniform Traffic Control Devices of the U.S. Department of Transportation.
These standards shall apply to islands at culs-de-sac.
(4) Curbs, berms and edgings. Provision of curbs, berms and pavement
edgings will depend in large measure upon the drainage chosen (i.e.,
open or subsurface), Materials normally used will be granite, cement
concrete or bituminous concrete, although other materials will be
considered. Curbs will be vertical, or within 10° of vertical,
when placed between traffic lanes and pedestrian sidewalks, unless
there are alternate provisions for pedestrian safety. Mountable edging
may be used elsewhere. When sidewalk is rebuilt, the existing granite
or bituminous curbing shall be replaced with like material or better.
(5) Future extension/expansion. Any road that is extended as results in further development thereby increasing traffic may have its classification changed by the Director. This would require the road to be upgraded to the road design criteria stated in Section
62-126. Neither building permits nor road acceptance may be granted before the road upgrade is complete, unless a performance bond for 150% of the entire road build out is posted, or the Planning Board selects as optional these roadway upgrade requirements.
[Ord. of 12-4-1991, § 20-80; Ord.
No. 2003.16, 2-4-2003]
(a) Required. Adequate allowance shall be made for safe and convenient pedestrian traffic, either actual or anticipated. Minimum provision for pedestrians shall be an all-weather sidewalk on one side of a street, at least five feet (1.5 m) wide. See Section
62-134, constructing sidewalks, for construction details.
(b) Curb ramps. Appropriate ramps sloped no greater than one inch of
height per foot of horizontal distance (8.33%) shall be used at all
locations where a pedestrian sidewalk must cross a curbline to meet
a crosswalk, whether at a street intersection or at a midblock location.
Ramps shall not feather in to the roadway surface, but shall have
a vertical termination approximately 1/4 inch to 3/8 inch in height,
aligned with the normal curbline. Ramped surface shall be broomed
or scored to provide a reasonably nonskid surface, and shall contrast
in texture with the normal surface of the sidewalk and roadway.
[Ord. of 12-4-1991, § 20-81; Ord. of 8-4-1998(7); Ord. No. 2003.16, 2-4-2003; Ord. No. 2005.95, 10-4-2005]
Construction and maintenance of curb cuts and driveway aprons are normally the responsibility of the owner of the property served, although legally a part of the public way. All such features shall be constructed only with a valid permit from the Director as provided in Section
62-171.
(1) Curb cuts will be equal to the allowable width of the driveway apron
plus a radius on each side: a driveway radius shall be at least two
feet but no more than 12 feet, and in no case shall the radius exceed
the width of the esplanade.
(2) The width of the driveway apron between the curbline and the property
line will be limited according to the type of use intended, and in
conformance with the following schedule:
a. Type I-A: Residential use; a single-family residence or a duplex
structure. Driveways up to 24 feet may be allowed by the Director
for public safety reason, provided a written request is submitted
to the Director for approval. Note: Duplex dwellings may have separate
twelve-foot driveways for each unit provided that they are on opposite
sides of the structure and are not interconnected.
b. Type I-B: Residential use; multifamily building with off-street parking
facility and driveway for two-way travel (16 feet), unless otherwise
approved by the Director for a width not to exceed 24 feet. Applicant
must submit request in writing to the Director.
c. Type II-A: Business use; non-highway related uses with a single drive
(20 feet) for both entrance and exit to/from off-street parking areas
for use by customers and employees and light delivery vehicles, unless
otherwise approved by the Director for a width not to exceed 24 feet.
Applicant must submit request in writing to the Director.
d. Type II-B: Alternate to Type II-A for separate entrance and exit
drives to parking area. Width, 16 feet; minimum separation, 32 feet.
e. Type II-C: (Note: "Highway related use" shall mean businesses engaged
in selling, leasing or servicing motor vehicles, or parts or accessories
thereof, which normally requires that the motor vehicle be located
at the business site.) Business use; highway related uses having a
single drive for both entrance and exit to off-street parking, for
use by both customers and employees and by delivery vehicles (24 feet).
f. Type II-D: Alternate to Type II-C for parking areas having separate
entrance and exit driveways. Width, 16 feet; minimum separation, 32
feet.
g. Type III-A: (Note: Industrial sites may have automobile parking for
employees and visitors separated from the truck parking or loading
areas, in which case, the Type I-B or II-A provisions shall apply
to the autos.) Industrial driveways for large trucks, buses or other
motorized equipment, having a single driveway, 40 feet wide, for both
entrance and exit to off-street parking and/or loading areas, or similar.
h. Type III-B: Alternate to Type III-A for separate entrance and exit
driveways to/from off-street parking/loading areas. Width of drives,
24 feet; minimum separation, 48 feet.
(3) Driveway aprons shall be located no closer to the side line of the lot served (or extension thereof at right angles to the front property line) than the allowable width of the driveway given in Subsection
(2) of this section. Spacing between adjacent driveways will be equal to the combined width of the driveways, as given above.
(4) Driveway aprons shall be located no closer to an intersection than
25 feet. No driveways may be located within any intersection.
(5) Driveways to corner lots, or through lots shall gain access from
the street of lower classification when a lot is bounded by streets
of two different classifications. The restriction shall appear as
a note on the plan and as a deed restriction. Also, the lots legal
frontage shall be determined by this requirement. In extenuation circumstances
where this requirement creates a hardship for the landowner, the Planning
Board can work with a landowner to determine the best location for
the structure.
(6) The driveway ramp shall lie completely between the gutter line and
the inner edge of the sidewalk (the edge nearest the center of the
street) where a sidewalk exists. In the case of an esplanade too narrow
to accommodate a ramp of reasonable flatness, the sidewalk grade may
have to be lowered in order to meet the above condition. In all cases,
alterations must be by permit from the Director.
(7) In the event of a change in the use of a driveway, a permit must
be obtained to enlarge a drive; and if the new use requires a narrower
drive, the Director may order the alteration at the expense of the
property owner.
(8) In the event of any construction by the City disturbing or destroying
an existing driveway apron, the City will construct a new, conforming
apron at no cost to the property owner, but the responsibility for
maintaining it will remain with the owner.
(9) If a driveway is discontinued, it shall be the responsibility of
the property owner to remove the driveway apron, and to replace the
curb in a manner satisfactory to the Director. If the property owner
fails to accomplish this removal, the City may elect to do the work,
and charge the cost to the property owner.
(10)
The Public Works Director, City Engineer and City Planner may
waive any of the above criteria providing they agree to such a waiver
unanimously, granting the waiver would serve a useful purpose, and
it does not adversely impact traffic flow and safety or create undue
adverse impacts on abutting properties. Appeals of the decision to
grant, grant with conditions, or deny the waiver shall be taken directly
to the City Council.
[Ord. of 12-4-1991, § 20-82; Ord.
No. 2003.16, 2-4-2003]
Normally, the portion of the street right-of-way lying between
the curb and the sidewalk (or the curb and the limit of the right-of-way
in the case of no sidewalk) is designated the esplanade, and is devoted
principally to grass or other ground cover. This area is also used
to locate utility poles, fire hydrants, traffic signs, and sometimes
trees. However, anything, either natural or artificial, which would
significantly reduce the visibility of drivers and pedestrians should
be removed or relocated. Shrubs, advertising signs (especially temporary,
moveable signs) and the like are not permissible except to the rear
of the sidewalk. Likewise, trees which have branches overhanging the
sidewalk or esplanade must be trimmed to a height of eight feet above
the sidewalk or esplanade. Esplanades are normally graded to a 1%
or 2% pitch toward the street, but in exceptional cases, may be steeper
if allowed by the Director.
[Ord. of 12-4-1991, § 20-83; Ord.
No. 2003.16, 2-4-2003]
(a) Signs shall be placed at the beginning and ending of every street, and at such intermediate points as shall be required by the Director, indicating the name of the street. Such signs shall conform to the requirements of Section
62-84.
(b) Adequate lighting shall be provided on all streets. The number and
location of all streetlights shall be installed according to the following
guidelines: in urban areas, the lights shall be located at all intersections
and on every other telephone pole, in non-urban areas light shall
be located at all intersections and to service three homes. For overhead
power, type and size of streetlights to be determined by public works.
If underground power is used, the applicant needs to coordinate with
the engineering department for City standard light fixtures and poles.
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These current guidelines may be reviewed on a case-by-case basis
by the committee responsible for capital projects if extenuating circumstances
exist. A plan showing all of the above details shall be furnished
for the committee responsible for capital projects approval prior
to installation.
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(c) The Planning Board shall review project from a planning point of
view, while the committee responsible for capital projects shall review
projects from an operations point of view.
[Ord. No. 2003.16, 2-4-2003]
Sight distance is the length of approaching roadway, which is
visible to the driver.
Stopping sight distance in the sum of the distance traveled
during driver perception/reaction time (2 1/2 seconds) and the
distance traveled while braking to a stop. The measurement is from
the driver's eye 3 1/2 feet above the pavement to a six-inch
height of object. Table 62-114-1 lists the design guidelines for stopping
sight distances at various speeds. Table is based on 10 feet of sight
distance for every mile per hour. In no case shall the minimum sight
distances be less than the MDOT Highway Design Guide requirements.
Table 62-114-1
Stopping Sight Distance
|
---|
Design Speed
(miles per hour)
|
Sight Distance
(feet)
|
---|
15
|
150
|
25
|
250
|
30
|
300
|
35
|
350
|
40
|
400
|
45
|
450
|
50
|
500
|
55
|
550
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Intersections at grade sight distance: Any intersection street
or road shall be so designed in profile and grading to provide minimum
sight distances measured in each direction. The height of eye of the
driver is 3 1/2 feet and the height of object (an approaching
car) is 4 1/4 feet. This section is based on Chapter 8 of the
Maine DOT Highway Design Guide. Refer to the most recent version of
this manual for sight distance requirements for various intersections.
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[Ord. No. 2003.16, 2-4-2003]
The owner may be required to investigate and determine the types and classifications of the subsurface soils, which shall be considered in the design of the proposed street(s). If in the opinion of the engineer, unsuitable subsurface soils are encountered during construction, the owner shall be required to excavate and remove the unsuitable material and replace it with suitable granular material at the expense of the owner, or the owner's engineer may provide an alternative means to deal with the poor soils. (See Section
62-129)