1983-28 Establishing Standards for Road ImprovementsKODIAK ISLAND BOROUGH
ORDINANCE NO. 83 -28 -0
AN ORDINANCE OF THE KODIAK ISLAND BOROUGH ASSEMBLY ESTABL HING
STANDARDS FOR ROAD IMPROVEMENTS.
The Kodiak Island Borough Assembly hereby ordains th. :
Section 1. Chapter 16.26, Standards For Road Improvements, 's created to read
as follows:
Chapter 16.26
Standards for Road Im.rovement
Sections:
16,26.010 General requirements.
16.26.015 Road classifications.
16.26.020 Minimum right -of -way afficway width.
16.26.025 Geometrics and profs - s.
16.26.030 Intersections.
16.26.035 Guardrails and sho der widening.
16.26.040 Road constructio standards.
16.26.045 Drainage.
16.26.050 Sign, subdivis •ns and road names.
16.26.010 General re.uire nts. A. These design, criteria,
specificat ons, an stan.ar. .etas s are minimum standards for the design of
improvements, kind and use material -, methods of construction, of roadways,
alleys, and drainage, which lie wt hin public rights -of -way or easements.
It is the policy of the Borough to adhere to these standards and specifi-
cations; however, if the design,standards cannot be followed as contained
herein due to unusual terrain, soil characteristics or drainage, the Engineer-
ing Department will consider,alternate solutions and may approve changes when
substantiated by a design analysis prepared by an engineer.
B. Any soils reports or certification documents of public improvements
submitted by the subdivider shall be certified by a registered professional
engineer licensed to practice engineering in the State of Alaska. This
certification shall signify that the documents were prepared by the engineer
or under his direct supervision and in accordance with the laws of the State
of Alaska governing such practices.
16.26.0 Road classifications. A. Local roads are designed to
provide direct a ess to n• v •ua properties.
B. Arteri• roads are designed to move through traffic at moderate
speeds to and rom major traffic generators, or into and /or out of a
community.
C. Col ector roads are designed to move traffic from local roads or
maintain r. ds to arterial roads.
D. •untain road is a road leading off of collector or arterial roads,
used for access to areas where sixty percent of the platted area exceeds
fifteen percent slope and where the average ground slope, as measured along
the c terline, exceeds ten percent.
Alleys are designed to provide secondary access to areas proposed for
mul ple dwellings, commercial or industrial uses or subdivisions where
se ice access, rear parking or loading is desirable.
16.26.020 Minimum right -of -way and trafficway widths.
A. Minimum right -of -way and trafficway width shall be as follows:
9 9
Minimum Minimum
Minimum Unpaved Paved
Road Classification Right -of -Way Trafficway Trafficway
Local road 50 feet 23 feet 20 feet
Collector road 60 feet 27 feet 24 feet
Arterial road 80 feet 31 feet 28 feet
Mountain road 60 feet 25 feet 22 feet
Alley 20 feet 18 feet 15 feet
Cul -de -sac (serving 40 feet 23 feet 20 feet
no more than six 7200 square
foot lots)
B. Rights -of -way shall be of sufficient width to accommodate the roadway
to be constructed with adequate room outside the roadway prism for installa-
tion of utilities.
.C. City streets shall be designed to meet the minimum trafficways
prescribed by the particular city involved.
16.26.G25 Geometrics and profiles. A. Horizontal Curves. Changes
in horizontal alignment of the roads shall be made through the use of horizon-
tal circular curves. The radii of which shall not be less than:
1. Local road, one hundred seventy -five feet;
2. Collector road, two hundred thirty -five feet;
3. Arterial road, four hundred twenty -five feet;
4. Mountain road, one hundred seventy -five feet.
B. Compound curves and broken -back curves should not be used. Reverse
curves should have an intermediate tangent of one hundred (100) feet or more,
unless the curve radii are three hundred (300) feet or more.
C. Gradients.
The maximum permitted road grade shall be eight percent except that
cul -de -sac areas and temporary turnarounds shall not exceed four percent. The
Borough Engineering Department may approve road grades to fifteen percent if a
plan and profile of the road is submitted by a registered engineer, and the
Borough Engineer concludes that safety standards are met.
16.26.030 Intersection. A. Streets shall intersect at an angle
close to ninety degrees as feasible, and in no event, at an angle less than
seventy -five degrees. Corner roundings with a twenty -foot radius shall be
required at intersections. Not more than two roads shall intersect at one
point.
B. The distance between intersection centerlines shall not be less than
two hundred feet. Intersection roads shall have no horizontal curves within
one hundred feet of an intersection.
C. Intersection road grades shall not exceed four percent within one
hundred feet of an intersection with the through road. The through road grade
shall not exceed seven percent at the intersection.
D. Intersection sight distances are as follows:
1. Intersecting local roads shall have a minimum sight distance of
two hundred feet.
2. Collector roads shall have a minimum sight distance of two
hundred seventy -five feet measured from the intersecting roads centerline.
3. Arterial roads shall have a minimum sight distance of four
hundred fifteen feet measured from the intersecting road centerline.
4. Mountain roads shall have a minimum site distance of two hundred
feet from the intersecting road centerline.
E. The subdivider shall obtain approval from the State of Alaska,
Department of Transportation and Public Facilities before intersecting with
any State -of- Alaska - maintained roads.
16.26.035 Guardrails and shoulder widening. Guardrail installation
and required shoulder widening shall be provided in accordance with Road
Design Memo #22, Guardrail Warrants, attached as Appendix "A" to this chapter.
16.26.040 Road construction standards. A. All roads shall be
constructed with subbase course of at least forty -two inches of non -frost
susceptible material with no more than ten percent by weight passing the No.
200 sieve. Of this subbase, the top six inches of capping material shall ha
no particles greater than three inches in diameter.
B. All roads shall be constructed with a base course of at least six
inches of two inch minus crushed rock.
Ordinance No. 83 -28 -0
Page 2
C. All roadway construction shall have all trees, brush and organic
material removed or burned prior to placement or construction of the road
subbase, unless an engineering plan for the use of corduroy, and /or the
overlay of gravel material of sufficient depth to withstand the anticipated
traffic use has been submitted and approved by the Borough Engineer.
D. All construction shall be contained within the right -of -way except
where the taking of additional slope easements is noted on the plat, and
additional easements are provided for utilities.
E. All construction shall be done in accordance with the latest edition
of the Alaska Department of Transportation and Public Facilities Standard
Specifications for Highway Construction.
16.26.045 Drainage. A. Drainage ditching and culverts shall be
provided of sufficient depth and size to carry seasonal high water volumes.
Minimum culvert size for drainage shall be twenty -four inches diameter with at
least a one percent drainage grade through the pipes.
B. The bottom of a roadway ditch shall be at least eight (8) feet beyond
the roadway subbase shoulder, with a 3:1 slope from the shoulder to the bottom
of the ditch.
16,26.050 Signs, subdivisions and road names. A. Road and subdi-
vision names shall be approved by the Platting Division.
B. Road and subdivision names shall not duplicate existing road or
subdivision names in spelling or sound such that they may be confused with
existing names. A road name shall duplicate an existing road name only where
a new road extends the alignment of an existing road.
C. Subdivision roads shall be identified and signed by the subdivider.
1. Each road within a subdivision shall be identified and signed
within fifty feet of its point of egress and ingress. Cul -de -sac roads shall
be signed and identified within fifty feet of their point of ingress.
2. Stop signs shall be provided at all collector and arterial roads
intersections within the confines of the subdivision.
3. All roads shall be signed in accordance with the most recent
edition of the Manual On Uniform Traffic Control Devices published by the U.S.
Government Printing Office.
D. All signs and sign support columns shall be of metal construction and
conform to the State of Alaska Sign Code.
Section 2: The provisions of this ordinance shall be effective immediately
upon passage and approval.
PASSED AND APPROVED by the Kodiak Island Borough Assembly this
day of , 1983.
ATTEST:
By
Borough Clerk
FIRST READING AND APPROVAL:
SECOND READING, PUBLIC HEARING, PASSAGE:
EFFECTIVE DATE:
RECOMMENDED BY:
Ordinance No. 83 -28-0
Page 3
KODIAK ISLAND BOROUGH
By
Borough Mayor