HomeMy WebLinkAboutstaff reportITEM NO.: 16 FILE NO.: MSP06-03
Name: Master Street Plan Amendment
Location: Area -wide
Request: Add Design Specification Table
Source: City Staff, Traffic Engineering
ROPOSAL / REQUEST:
The request is to add a table with design specifications for roads by classification
type of roadway. This table includes the design speed and service volumes,
maximum grades, sight distance requirements, horizontal radii as well as right-of-
way, paving width and sidewalk requirements. The table has been a part of the
Master Street Plan and was inadvertently left out of the draft for the current
Master Street Plan when it was approved.
The table proposed is the same as that in the earlier version of the Master Street
Plan, only updating the citation to a more current version of the ASSTO manual.
The `Design Specifications' table provides standards for each type of road —
Design Speed, Maximum Grade, Minimum Sight Distance, Minimum Horizontal
Radii, Minimum Horizontal Tangent Distance, Service Volume, Minimum Right-
of-way, Minimum Pavement, and Sidewalks.
The information included in the table is already in the Master Street Plan
document included with each street cross-section within the 'Design Standards'
section of the Master Street Plan. The table just provides an easy to use
summary of the standards for all the streets types in one place. When approved
this table will be made a part of 'Section 3: Design Standards' of the Master
Street Plan document. (attached is a copy of the Table)
NEIGHBORHOOD COMMENTS:
Notices were sent to the ordinance change contact list of some fifty
neighborhood groups, professional organizations, developers and engineers.
Staff has received one comment against the change from a property owner along
the alignment.
STAFF RECOMMENDATIONS:
Staff believes the change is appropriate.
DESIGN SPECIFICATIONS (as amended by Ordinance # 18,055)
Design
Principal
Minor
Minor
Consideration
Expressway
Arterial
Arterial
Collector
Res.
Res.
Design speed
55
45
1 40
30
25
20
(miles per hour)
Maximum grade
8%
8%
9%
12%
15%
16%****
at centerline
Min. sight
550'
400'
325'
200'
200'
200'
distance at
crest of
vertical curve
Min. horizontal
1700'
900'
600'
275'
150'
75'**
radius at centerline
(normal crown)
Min. horizontal
1000'
500'
500'
235'
N/A
N/A
radius at ceuferline
(super -elevated
Cross section)
Min. horizontal
600'
300'
200'
100'
50'
N/A
tangent distance
bet. reverse
curves
Service volume
40,000
25,000
18,000
5,000
2,500
Max. of
35 lots
Min. right-of-way
200'
110'
90'
60'
50'
45'
Min. pavement
48'+shld
66'****
59'
36'
26'
24'
width (back to
& median
back of curb)
Sidewalks
may be***
both
both
one
one
None
required
sides
sides
side
side
NOTE All minim um design standards comply with
1984 AASHTO Policy Design Man ual
* Corresponds to a 200 ft. horizontal tangent distance between reserve curves.
`Minimum standard corresponds to design speed of 15 mph
Sidewalks may he required in areas ofintense development
*** 2 divided 26 ft. lanes with proper provision for future widening.
*� *A -may he increased to 18% with approval.
#No more than 351ots.