chapter 18 – neighborhood traffic safetychapter 18 – neighborhood traffic safety section 18.3...
Post on 24-Aug-2020
5 Views
Preview:
TRANSCRIPT
CHAPTER 18 – NEIGHBORHOOD TRAFFIC SAFETY
TABLE OF CONTENTS
Section Title Page
18.1 General ....................................................................................................................... 18-1
18.1.1 Intended Use...............................................................................................................................18-1
18.1.2 Traffic Calming for New Street Design ...................................................................................18-1
18.1.3 Roundabouts and Mini Roundabouts ......................................................................................18-1
18.2 Traffic Safety Problems............................................................................................. 18-1
18.2.1 Speeding......................................................................................................................................18-1
18.2.2 Measuring Speed of Roadway ..................................................................................................18-2
18.2.3 Intrusion (Cut-Through Traffic) ..............................................................................................18-2
18.2.4 Pedestrian Safety .......................................................................................................................18-2
18.3 Traffic Calming Design Criteria ................................................................................ 18-2
18.3.1 Speed Limit Signs ......................................................................................................................18-2
18.3.2 Speed Humps..............................................................................................................................18-2
18.3.3 Dips .............................................................................................................................................18-2
18.3.4 Mini Roundabouts .....................................................................................................................18-3
18.3.5 Neckdowns..................................................................................................................................18-3
18.3.6 Traversable Barriers .................................................................................................................18-3
18.3.7 Deviations (Chicanes) ................................................................................................................18-3
18.3.8 Raised Intersections...................................................................................................................18-3
18.3.9 Neighborhood Identification Island .........................................................................................18-3
18.3.10 Drop Off Zone for Schools ........................................................................................................18-3
18.3.11 Intersection Chokers .................................................................................................................18-3
18.3.12 Turn Prohibitors........................................................................................................................18-3
18.3.13 Semi-Diverters............................................................................................................................18-3
18.3.14 Lane Eliminating Choker – Loveland (GMA and city limits) ...............................................18-3
18.3.15 Diagonal Diverters .....................................................................................................................18-3
18.3.16 Realigned Intersections .............................................................................................................18-4
Larimer County Urban Area Street Standards – Repealed and Reenacted April 1, 2007 Page 18-i Adopted by Larimer County, City of Loveland, City of Fort Collins
LIST OF TABLES
This Chapter Does Not Contain Tables
LIST OF FIGURES
Figures are Located at End of Chapter
Figure 18-1 Neckdowns
Figure 18-2 Traversable Barriers
Figure 18-3 Deviations (Chicanes)
Figure 18-4 Raised Intersections
Figure 18-5 Neighborhood Identification Island
Figure 18-6 Drop Off Zone for School
Figure 18-7 Intersection Choker
Figure 18-8 Turn Prohibitors
Figure 18-9 Semi-Diverters
Figure 18-10 Lane Eliminating Choker
Figure 18-11 Diagonal Diverters
Figure 18-12 Realigned Intersections
Page 18-ii Larimer County Urban Area Street Standards – Repealed and Reenacted April 1, 2007
Adopted by Larimer County, City of Loveland, City of Fort Collins
Chapter 18 – NEIGHBORHOOD TRAFFIC SAFETY Section 18.1 General
CHAPTER 18 – NEIGHBORHOOD TRAFFIC SAFETY
18.1 GENERAL
This chapter presents acceptable methods of neighborhood traffic calming that are determined by
the Local Entity to be necessary for existing Local and Minor Collector Roadways. This chapter
also provides for specific design criteria for a number of traffic calming methods.
18.1.1 Intended Use
The necessity or desire for traffic safety and calming stems from the perception that
Local and Minor Collector Roadways, particularly in residential areas, do not always
function as intended. These roadways should be low traffic volume roadways used for
direct access to residences on the street. They are also intended as a multi-modal system
that is shared by vehicular, bicycle, and pedestrian traffic equally, in a manner that
minimally impacts residents in these areas.
18.1.2 Traffic Calming for New Street Design
The devices presented in this chapter are generally not intended for use on new roadways.
New roadway design is addressed in Chapter 7, Street Design and Technical Criteria.
New (local streets and minor collectors) are to be designed to minimize cut through
traffic, high volumes, and high speed operation and to maximize the efficiency of the
roadway to provide vehicular access and bicycle and pedestrian traffic.
18.1.3 Roundabouts and Mini Roundabouts
Roundabouts and Mini Roundabouts, considered traffic control measures, are included in
Chapter 8, Intersections. These traffic control measures may be used in new or existing
street design if the appropriate criteria are met.
18.2 TRAFFIC SAFETY PROBLEMS
Some residents in certain residential areas maintain that excessive speed, volume, or cut-through
traffic is unacceptable. The resident believes the presence of too many vehicles traveling at high
speeds diminishes that neighborhood’s quality of life. Traffic calming measures are intended to
minimize these issues and return the quality of life to the neighborhood. Care must be taken by
the designer so that the installation of traffic calming devices does not create unintended hazards
that delay emergency response or jeopardize the safety of bicyclists, pedestrians or motorists.
18.2.1 Speeding
Speeding may occur on roadways that allow the driver to feel safe while exceeding the
posted speed limit. Factors that contribute to this perception include long, unbroken lines
of sight, steep roadway grades, wide roadways, low density developments, low pedestrian
activity, and large building setbacks. In addition, speeding may occur when the street
functions as a higher classification street than originally intended.
Larimer County Urban Area Street Standards – Repealed and Reenacted April 1, 2007 Page 18-1 Adopted by Larimer County, City of Loveland, City of Fort Collins
Chapter 18 – NEIGHBORHOOD TRAFFIC SAFETY Section 18.3 Traffic Calming Design Criteria
18.2.2 Measuring Speed of Roadway
The standard method of measuring speed on any street is the determination of the 85th
percentile speed. The 85th percentile speed is the speed at which or below which 85
percent of the vehicles travel. If the 85th percentile speed is at or below the posted speed
limit, a speeding problem does not exist. However, if the 85th percentile speed is over the
posted speed limit by 5 miles per hour or greater, either the posted speed limit may be
inappropriate or a speeding problem may exist. Many other factors must be evaluated for
determining speed limit.
18.2.3 Intrusion (Cut-Through Traffic)
Intrusion is increased volume or excessive non-local traffic along a neighborhood street.
This cut-through traffic is caused by drivers who use a Local Street to go through a
neighborhood and save time on their trip. Local Streets that are less impeded than other
local streets within the same neighborhood will often invite cut-through traffic. Routes
that are perceived to be time-saving will attract more traffic. This increased cut-through
traffic can cause a local street to function more like a Collector.
18.2.4 Pedestrian Safety
Pedestrian safety is a concern on streets experiencing speeding vehicles, cut-through
traffic, or a combination of these problems. The high concern areas are in the vicinity of
neighborhood schools and parks or mid-block pedestrian crossings, particularly on streets
with on-street parking. These areas require special consideration for the mobility and
safety of the pedestrian.
18.3 TRAFFIC CALMING DESIGN CRITERIA
For existing Local or Minor Collectors that are defined for Traffic Calming. Refer to the City of
Loveland’s Traffic Calming Procedures. Refer to the City of Fort Collins’ Traffic Calming
Procedures. This chapter describes design criteria for the engineered solutions. It does not state
when or where these improvements are to be used.
18.3.1 Speed Limit Signs
Refer to Chapter 14, Traffic Signals, Signing, and Striping
18.3.2 Speed Humps
Refer to Construction Drawing 1801F and 1802F for design criteria in Fort Collins
(GMA and city limits).
18.3.3 Dips
Refer to Chapter 8, Intersections, for standard Crosspan design.
Page 18-2 Larimer County Urban Area Street Standards – Repealed and Reenacted April 1, 2007
Adopted by Larimer County, City of Loveland, City of Fort Collins
Chapter 18 – NEIGHBORHOOD TRAFFIC SAFETY Section 18.3 Traffic Calming Design Criteria
18.3.4 Mini Roundabouts
Refer to Chapter 8, Intersections for Mini Roundabout design requirements.
18.3.5 Neckdowns
When neckdowns are used they must be designed to maintain a constant cross fall in the
pavement surface. Refer to Figure 18-1 for design criteria.
18.3.6 Traversable Barriers
Refer to Figure 18-2 for design criteria.
18.3.7 Deviations (Chicanes)
Refer to Figure 18-3 for design criteria.
18.3.8 Raised Intersections
Refer to Figure 18-4 for design criteria.
18.3.9 Neighborhood Identification Island
Refer to Figure 18-5 for design criteria.
18.3.10 Drop Off Zone for Schools
Refer to Figure 18-6 for design criteria.
18.3.11 Intersection Chokers
Refer to Figure 18-7 for design criteria.
18.3.12 Turn Prohibitors
Refer to Figure 18-8for design criteria.
18.3.13 Semi-Diverters
Refer to Figure 18-9for design criteria.
18.3.14 Lane Eliminating Choker – Loveland (GMA and city limits)
Refer to Figure 18-10 for design criteria.
18.3.15 Diagonal Diverters
Refer to Figure 18-11 for design criteria.
Larimer County Urban Area Street Standards – Repealed and Reenacted April 1, 2007 Page 18-3 Adopted by Larimer County, City of Loveland, City of Fort Collins
Chapter 18 – NEIGHBORHOOD TRAFFIC SAFETY Section 18.3 Traffic Calming Design Criteria
18.3.16 Realigned Intersections
Refer to Figure 18-12 for design criteria.
Page 18-4 Larimer County Urban Area Street Standards – Repealed and Reenacted April 1, 2007
Adopted by Larimer County, City of Loveland, City of Fort Collins
20'-0" min. FL to FL
4'-0" Wal (4" Thick)
6" Vertical C & G
15' R (Typ.)
Match Existing Flow Line
~~ ---
Narro;1 --il-_l_JL_L_..L_L~---1---+---1.-~~...1.--_....1-7 -
Match Existing Flow Line
NOTES:
I ,___ __ 31 '-5" ------< /
I I I
PLAN VIEW
1. Only full sections of sidewalk may be removed.
NECKDOWNS
15' R Match Existing Flow Line
LARIMER COUNTY DESIGN REVISION NO: URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00
FIGURE
18-1
]
I. J~-1
NOTE:
10' (min.
2'
Planter Area
4'
I I
Section A-A Not to Scale
I O ii
0
1 . Jersey Barriers may be used as temporary Traversable Barriers upon approval.
TRAVERSABLE BARRIERS LARIMER COUNTY DESIGN REVISION NO:
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00
FIGURE
18-2
NOTES:
C:
~ b 0 T"""
50' R (min.)
1 . Deviations must cause driver to change directions. 2. Medians may be included in design to assist in the separation of traffic. 3. Narrow roadway wanders in a street right of way; requires wide ROW. 4. For min. curb radii, see Chapter 8, Tables 8-1 & 8-2.
DEVIATIONS (CHICANES) LARIMER COUNTY DESIGN REVISION NO:
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00
FIGURE
18-3
0
~ I - -
-I - IA -
! ~ la= ~ ! I I~ I I
I !I II - -
I ~ I ~
I
I 0 I
] ~
I PLAN VIEW
[~ ~
It ~ .. ~~~··.·-,.I [<r,lin>
L~~ r SECTION A-A
RAISED INTERSECTIONS LARIMER COUNTY DESIGN REVISION NO: FIGURE
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00 18-4
20'
6' (min.)
FL to FL
PLAN
20'
=;J£rH-a-rd_s_c-ap_e _____ _ Q~.-~.~,=il--------~ t:::Ut]
PROFILE
NOTE:
1. Sign cannot impair sight distance. 2. The sign (in Fort Collins) must meet the following criteria:
•Sign must have a max height of 5'. • sign surface area must be 24 square feet (max.) • The word "neighborhood" must be included in the signage lettering.
NEIGHBORHOOD IDENTIFICATION ISLAND LARIMER COUNTY DESIGN REVISION NO:
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00
FIGURE
18-5
0 I
C\I
E s . w :::i
<ii 9 -~ > ~ c b ,£;
u5 (]) LO 2 z E <( (]) > _J al
a... 0... ~ 0 C: 0 0
DROP OFF ZONE FOR SCHOOL LARIMER COUNTY DESIGN REVISION NO: 1 FIGURE
URBAN AREA FIGURE STREET STANDARDS DATE: 04/01/07 18-6
- -
I ,( ,(
~ I b C LO I
◊ I ◊ ~
b C C') I I
U5!S dais <( I
<(
z z <( 0 - _J
~ 11 ll I 0... 0
w Cf)
U5!S dais
{"U!W) ,G~
c-u,w) I ,9
◊ ◊ (U!W) I
,17
,9
eue71 9)1!8
INTERSECTION CHOKER LARIMER COUNTY DESIGN REVISION NO: FIGURE
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00 18-7
"DO NOT ENTER" Sign: R5-1 ----
NOTE:
Landscaping or Hardscaping as
Required by Local Entity
15' R (min.)
15' R (min.)
30' (min.)
16'
I
"NO TURNS"
s;gn, R3--3 =\ ,___ ____ •I
Full Lane Wk!th 1--
"NO LEFT TURN" Sign: R3-1
-----
1 . Any landscaping provided must be maintained by HOA City Forester or private owner; otherwise, area must be hardscaped.
TURN PROHIBITORS LARIMER COUNTY DESIGN REVISION NO: FIGURE
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00 18-8
"DO NOT ENTER" Sign: R5-1
"NO TURNS" Sign: R3-3
8
•
---------------- ---------------"NO TURNS"
Sign: R3-3
D 0
NOTE:
I I
0
"DO NOT ENTER" Sign: R5-1
1 . Any landscaping provided must be maintained by HOA, City Forester or private owner; otherwise, area must be hardscaped.
SEMI - DIVERTERS LARIMER COUNTY DESIGN REVISION NO:
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00
0
FIGURE
18-9
NOTE:
.• .. ·. ·.
· .. :.~··.:
·.•':d./~:
··i. ·'/ . _ .... . ~ ~ ·. •: .. • .......
,... .: . .. ,·. ·:· . . ... .
•. 4 .
•·· .. :.· ~·-- :. ·.,~ •' ~-.. , ···• .~; . ·:. . : .. ., .. .•.: .... : .. · ..
'!'-·.
·.. ~ .. ,.;J . . : : ~.
A. . ·•
..... · ..
·: ·•·
... ..- ~4 .... .-
. ·1,' . ·: . .. 4.
.. ·. ::4: · ... ·· .•. : •.. . ..
· .. ~ · ... ·.~ . · .-. : •...
A. . ·.
~., ... .·,1.• . .. ·
. ... · ...•. •. ·. •.·
=BikePath\ I
I ◊
I ◊
0
8 ~ 5'R
10'-16'
I I w I
FL
.. 4 ... . · ·. ·.
.. ~ ~· . .· •:· .
. A".· ..
. ~: .. ·~: : . ~ . .a·:: :
·· . .;, . ~ .. _.;,, .... ......
. :·• ·.. . .. '.··
::~(.~Sidewalk .. .,,, : • 4 .
~ ...• ·•. ,· .. ~. : . . 45· . · ... : .-. ~ ... ~. ~: -·. · . . . .
. . .... .:.-
~· ... : . 4.' ! · ..
. ... . ··•·: ~... :·
.:: .. :: {
.. :· ..• :· · ..... .. . •·.""-· ·'.
.; .. . ·.: . ..... .a· :
·."" ... · .. ·~ .
. :· . A:. ·!~ . -. ·~
. ·" ·. : .... ' ·4
.· . .· ,..·
14. ',' .. . :..·
1/' ', ' .. .. ::·: .~ ·= .
;". · .. · .. . ..
·.~ .. · _.· .•..
C\I T"""
C
~ b C')
1. 2 lanes narrow to 1 lane. Cars must queue and take turns to travel through single lane.
LANE ELIMINATING CHOKER LARIMER COUNTY DESIGN REVISION NO: FIGURE
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00 18-10
]
LARIMER COUNTY URBAN AREA
STREET STANDARDS
I
I ~I
PLAN VIEW
SECTION A-A
DIAGONAL DIVERTERS
I II ii
0
Planter is to act as barrier.
/ 3'-0"
DESIGN REVISION NO: FIGURE FIGURE DATE: 08/07/00 18-11
I (I !I Stop Sign
I I I I I I I I I
z ~ b
I
b 0 T"""
--------------------~ 111 l□
40'-0"
D e
8 Stop Sign
n l b
■-------------■ ~ C')
1111):n j ~====;:::::::::;=
0
0
0
REALIGNED INTERSECTIONS LARIMER COUNTY DESIGN REVISION NO: FIGURE
URBAN AREA FIGURE STREET STANDARDS DATE: 08/07/00 18-12
top related