A.
Preservation of existing resources. All significant existing natural,
human-made, or scenic resources shall be preserved and protected to
the greatest extent possible. Such resources include, but are not
limited to: historic structures, stone walls, steep slopes with a
gradient greater than 25%, ledge outcroppings, specimen trees and
stands of trees, including rare and unusual flora and fauna, endangered
species, species of special concern, watercourses, ponds, wetlands,
scenic vistas, ridge lines and any other significant geological features
such as eskers, kames or kettles.
B.
Alternate criteria. Any deviation from the road criteria established
in this section shall require approval from the Board of Selectmen,
Commission, and Town Engineer.
C.
Road classifications. Classification of roads shall be determined
by the Commission. A listing of road classifications for roads within
Old Lyme is included as an appendix to these Design and Construction
Standards.[1] All proposed roads in the subdivision and any existing
road abutting the subdivision shall be classified as one of the following:
(1)
Collector road (business/commercial/industrial): a moderately heavily
traveled road that is presently receiving, or has the potential to
receive, traffic from two or more local roads, private roads or dead-end
roads.
(2)
Local residential road: a road primarily providing access to abutting
lots used for residential purposes, including dead-end roads.
(3)
Private residential road: a road that is privately owned and privately
maintained. A private road is subject to the restriction that such
road shall not be offered to, accepted by, or maintained by the Town
of Old Lyme. In general, a private road is a road owned and maintained
by a legally constituted homeowners' association, and constructed
in accordance with the standards for private roads which are part
of the Subdivision Regulations[2] at the time of approval of the subdivision.
[1]
Editor's Note: Said listing is on file in the Town offices.
A.
Road width. The minimum pavement width of roads, as measured from
face to face of curbs, shall be as follows:
|
Road Classification Chart
| |||
|---|---|---|---|
|
Road Classification
(feet)*
|
Width of R.O.W.
(feet)
|
Width of Shoulder
(feet)
(unpaved)
|
Width of Traveled Portion of Pavement
(feet)
|
|
Collector road
|
60
|
8
|
30
|
|
Local residential road
|
50
|
4
|
24
|
|
Private residential road
|
50
|
4
|
22
|
|
* When curbing is necessary, the width of the curbing shall
be added to the width of the traveled portion of the pavement.
|
B.
Right-of-way. For every road, the right-of-way lines on each side
of the road shall be parallel or shall be concentric arcs, and all
intersections of right-of-way lines shall be rounded by a curve having
a radius equal to the required curbline radius, but not less than
25 feet.
A.
General. Roads shall be designed so as to avoid excessive cuts and
fills and to avoid a combination of steep grades and sharp curves.
B.
Minimum. The minimum gradient on any road shall be 1%, except turnarounds,
which shall be 1.35%.
C.
Maximum. Maximum gradients shall be as follows:
(1)
Local road or private road: 10%.
(2)
Collector road: 10%.
(3)
Turnarounds: 4%, the maximum permitted gradient for the entire required
turnaround diameter.
(4)
Intersection, local residential road or private residential road:
3%, for a minimum tangent distance of not less than 50 feet as measured
from the gutter line of the intersected road to any change in gradient.
(5)
Intersections, collector roads: 3%, for a minimum tangent distance
of not less than 100 feet as measured from the gutter line of the
intersected road to any change in gradient.
A.
Minimum. The horizontal and vertical alignment of local residential
roads shall be based on a 30 mph design speed and provide for a minimum
stopping sight distance of 200 feet. For collector roads, a design
speed of 35 mph shall be used and a minimum stopping sight distance
of 250 feet provided.
B.
Determination. Sight distances shall be determined on the basis of
height of eye-height of object, headlight beam and horizontal location
of eye, and object design criteria currently used by the State of
Connecticut Department of Transportation.
A.
Curve tangent and radius. For all roads, the minimum tangent length
between horizontal curves shall be 100 feet. The minimum radius of
center line curvature shall be 200 feet for local roads and 300 feet
for collector roads.
A.
Gradient transition. Parabolic vertical curves for transition between roadway gradients shall be provided on all roads to insure adequate sight distances in accordance with the minimum requirements specified in § 187-23 and to provide a rate of change of gradient that assures safe vehicle operation and does not cause discomfort to vehicle occupants.
B.
Curve length. The required length of vertical curve shall be based upon criteria identified in § 187-23, with the following requirements being the minimum acceptable. Minimum vertical curve length equals minimum length multiplier (K) times algebraic difference of grades in percent.
C.
Minimum curve length. Vertical curves shall have a minimum length
of 100 feet.
A.
General. The following standards shall apply to all intersections:
(1)
No more than two roads shall intersect at any one location.
(2)
Cross (four-cornered) intersections shall require approval by the
Board of Selectmen and/or Commission.
(3)
Spacing of intersections, as measured between center lines, shall
be at least 200 feet.
(4)
Driveways shall not be located any closer than 50 feet from an intersection.
(5)
Wherever possible, roads shall intersect at a 90° angle, or as
close thereto as is practical. In no event however, shall an intersection
be allowed where the angle of intersection is less than 75° within
100 feet of the intersection.
(7)
The visibility at intersections (intersection sight distance) shall
be in accordance with provisions for intersections at grade as specified
in the Connecticut Department of Transportation Highway Design Manual,
latest revision.
(8)
Sufficient clearing and regrading shall be accomplished to meet the sight distance visibility requirements of Subsection A(7) of this section, and no structures, fences, walls, hedges, rock, shrubs, trees or other landscaping shall be permitted to obstruct such visibility.
(9)
Permanent sight line easements shall be provided on all private property
so as to maintain the sight line requirements established in this
subsection. In addition, no objects of any kind that are located on
private property outside the limits of a permanent sight line easement
shall be permitted to extend or protrude within the plane of such
easement. In the case of trees, all foliage shall be trimmed up to
a minimum height of six feet as measured from the top of curb or edge
of pavement adjacent to the nearest road.
B.
Layout. The layout of the turnaround shall be in accordance with
the most current Standard Detail Drawings for either a circular or
offset type turnaround.
C.
Snow storage reserve area. Unless otherwise approved, an open unrestricted
area shall be reserved at the end of all turnarounds for the storage
of snow. Such area shall be located at the end of the turnaround between
the curb and the right-of-way line for a distance of 25 feet on each
side of the extended road center line. This area, which shall be delineated
on the record subdivision map, shall be free from all obstructions,
including, but not limited to, driveways, mailboxes, landscaping and
fences.
A.
General. For all roads, the shoulder area extending from the back
of the curbing to the right-of-way line shall be excavated to a depth
of at least six inches, and then backfilled and final graded with
not less than six inches of topsoil, as hereinafter specified.
B.
Grading of shoulder areas. The shoulder areas shall be graded so
as to slope toward the top of curb at a cross slope of 3/8 inch per
foot unless otherwise approved by the Board of Selectmen or the Town
Engineer due to special conditions encountered during construction.
C.
Grading beyond shoulder areas. Areas outside of the shoulders shall
be graded up or down to existing grades, at a slope not to exceed
two feet horizontal to one foot vertical. In rock cuts, slopes of
one foot horizontal to not more than six feet vertical shall be allowed,
but care shall be taken to insure that all exposed rock is stable
and free from faults, cracks or other infirmities which might lead
to collapse or flaking.
D.
Special conditions. The Board of Selectmen or the Commission may
require additional measures to be taken to maintain the stability
of slopes, and to control groundwater seepage, under prevailing soil
conditions encountered during construction. These measures may include,
but not necessarily be limited to, a decrease in the amount of slope,
stabilization blankets or grids, stone slope protection, plantings,
wedge drains, underdrains, terracing, drainage swales or retaining
structures. In cases where the exposed face of a cut slope consists
of decomposed, flaking, highly fractured or unstable rock, slopes
shall be flattened so as to protect public safety and minimize future
maintenance.
E.
Limits. No cut or fill slopes shall extend beyond the limits of the
right-of-way onto private property unless appropriate slope rights
are acquired which provide a perpetual right, running with the land
in favor of the owner of the road, to enter upon said private property
for purposes of constructing, maintaining and repairing such slopes.
In the absence of such slope rights, appropriate retaining structures
shall be constructed to prevent encroachment on adjoining private
property.
F.
Trees. If, in the opinion of the Board of Selectmen or Commission,
a slight modification of the shoulder or slope would result in the
saving a valuable shade tree, the Board of Selectmen or Commission
may authorize such variation.
A.
General. Except as provided herein, where curbs are proposed or installed,
all new roads shall be constructed with Cape Cod style (aka mountable)
curbs. Curbs shall be constructed along the edge of road pavement
in accordance with the dimensions and details shown in the most current
Standard Detail Drawings for: a) newly constructed roads, Cape Cod
(modified curb); or b) existing roads, bituminous concrete lip curb.
Alternate type curbing may be permitted by the Board of Selectmen
or Commission for unique areas such as historic districts.
A.
General. For new road construction, all utilities within the right-of-way
of a road or easement area shall be located underground and installed
as shown in the most current Standard Detail Drawings for underground
utility assignments, except in special circumstances where such location
may reasonably be expected to result in damage to historic features
or areas of environmental concern. Individual services shall be extended
to the right-of-way or easement line prior to the placement of any
pavement. Installation of utilities within existing road rights-of-way
shall be as approved by the Town Engineer. To the extent possible,
separation distances shall be maximized from existing municipal utilities.
A.
Guide rails. Guide rails shall be installed wherever necessary to
minimize the risk of personal injury or property damage resulting
from vehicle departure from the right-of-way. In general, guide rails
shall be installed at the following locations:
(1)
Embankments. Such protective barriers shall be required on any roadway
section constructed on an embankment which places the roadway surface
four feet or more above the existing ground surface at the toe of
the embankment slope. These embankment slopes are not steeper than
four feet horizontal to one foot vertical.
(2)
Culvert endwalls. Such protective barriers may be required at culvert
endwalls, depending on the height of the endwall and its proximity
to the edge of the road.
(3)
Roadside obstacles. Such protective barriers may be required to shield natural or man-made fixed object hazards, including, but not limited to, trees, rock outcrops, ditches, retaining walls, bridge abutments and permanent bodies of water. Where marginal situations occur with respect to the placement or omission of a guide rail, or where it is determined that a vehicle striking a guide rail could potentially be more severely damaged than an accident resulting from hitting an unshielded roadside obstacle, the Board of Selectmen or the Town Engineer may approve the use of an object marker in accordance with § 187-35D.
B.
Fencing. A securely anchored PVC-coated chain-link fence four feet
in height shall be installed wherever necessary to minimize the risk
of personal injury. In general, fencing shall be installed at the
following locations:
A.
Places. Road lighting shall be provided if required by the Board
of Selectmen or Commission at any location where illumination in darkness
is necessary to minimize the risk of accidents involving vehicles
or pedestrians or to assure safe and convenient vehicle and pedestrian
passage. In general, the placement of lighting should be limited to
intersections.
B.
Nature. Lighting standards and luminaires shall conform to the most
current utility company standards and shall be full cut-off luminaires
with fiberglass poles, unless otherwise approved by the Commission.
They shall be so located as to safeguard against discomfort glare
and visibility glare and avoid adverse effects from illumination upon
the use, enjoyment and value of adjacent property.
A.
General. All new roads shall be accurately monumented to allow the
ready determination of points along all right-of-way lines. Monuments
shall be placed at all points of tangency and points of curvature
and elsewhere as required to permit seeing from one monument on a
line to another on the same line.
A.
General. Road and other location names shall be approved by the Commission,
and be so distinctive as to preclude possible confusion with other
existing roads and locations within the Town. Roads which are designed
to connect and align directly with other roads shall bear the same
name. Road names shall be appropriate to the character of the Town
and, wherever possible, shall reflect the geographic or historic aspects
of the area in which the road is located. Road name signs shall be
installed at all intersections. Such signs shall be erected in such
places as to assure clear legibility by vehicle operators and shall
conform to the dimensions and details shown on the Standard Detail
Drawings.
A.
General. Traffic control devices, including signs, pavement markings,
object markers, and other regulatory devices, shall be provided in
such places as may be necessary to minimize the risk of accidents
involving vehicles or pedestrians and to assure safe and convenient
vehicle and pedestrian passage.
B.
Signs. The design and placement of regulatory, warning and guide
signs (stop, speed limit, no outlet, etc.) shall conform to the most
current edition of the Manual of Uniform Traffic Control Devices.
C.
Pavement markings. The location, type, color, width and patterns
of pavement markings and object markers shall conform to the most
current edition of the Manual of Uniform Traffic Control Devices.
In general, pavement markings shall include stop lines and crosswalks.
Longitudinal pavement markings (center lines), to delineate the separation
of traffic flows in opposing directions, shall only be required on
collector roads or other roads as required by the Board of Selectmen
or Commission.
D.
Object markers. The design and placement of object markers shall
conform to the most current edition of the Manual of Uniform Traffic
Control Devices.
A.
General. The Commission may require the installation of sidewalks
along roads and in pedestrian easements. In general, when required,
the installation of sidewalks should be limited to projects located
adjacent to arterial, collector, and subcollector roads; adjacent
to local roads within 1.5 miles of a school, library or recreational
facility; in the vicinity of public or quasi-public buildings, playgrounds,
shopping areas, transit stops or high-density residential areas; and
at other locations when deemed necessary by the Commission where the
expected or probable volume of pedestrian traffic makes sidewalks
necessary or appropriate in the interest of public safety and convenience.
B.
Location and dimensions. Sidewalks shall be a minimum of five feet
in width and shall be located within the road right-of-way line, as
shown on the Standard Detail Drawings. Sidewalks shall be carried
across all driveway crossings with driveway grades adjusted to maintain
a uniform sidewalk height above the edge of roadway pavement.
C.
Handicap ramps. Curb cuts shall be provided at all pedestrian crosswalks
to provide access for the safe and convenient movement of physically
handicapped persons. Such curb cuts shall conform to the most current
state statutes and the Americans with Disabilities Act Accessibility
Guidelines.
D.
Maintenance. Prior to acceptance of a completed road by Town Meeting, it shall be the developer's sole responsibility to provide normal maintenance as specified in § 187-16.
E.
Pedestrian easements. In areas where the proposed road system does
not conform to a convenient pattern of pedestrian circulation, particularly
in the vicinity of parks, schools, playgrounds or other public or
semipublic places, the Board of Selectmen or Commission may require
the establishment of easements for pedestrianways, which will be a
minimum of 10 feet in width. The surfacing, grade, and other specifications
for such pedestrian easements shall take into consideration the topography,
anticipated volume of use, erosion control, access for disabled persons,
and the character of the area in the Town of Old Lyme.
F.
Bikeways and multi-use trails. The Board of Selectmen or Commission
may require bikeways or multi-use trails to be constructed when deemed
necessary for public safety or when such bikeways will contribute
to a coherent integrated system of bikeways or trails providing an
alternative means of transportation for the Town. A bikeway may be
either a separate trail or path for the exclusive use of bicycles
or a portion of the roadway which has been designated for preferential
or exclusive use of bicycles, separated from the roadway by a paint
stripe or curb or other similar device. The surfacing, grade, and
other specifications for such bikeways and multi-use trails shall
take into consideration the topography, anticipated volume of use,
erosion control, access for disabled persons, and the character of
the area in the Town of Old Lyme. For the purposes of these Design
Standards, a multi-use trail is a trail or pathway that is designed
to accommodate pedestrians, bicyclists, runners, rollerbladers, horses,
people in wheelchairs and those wheeling strollers.
