HomeMy WebLinkAbout1988-03-07; Traffic Safety Commission; ; Requests to install a continuous two-way left-turn lane (2WLTL) on La Costa Avenue from the easterly side of the commercial area located immediately east of El Camino ReCITY OF CARLSBAD
TRAFFIC SAFETY CCll4ISSION
COfil4ISSION REPORT OF: March 7, 1988 ITEM NO. 6A
LOCATION: La Costa Avenue
INITIATED BY: Robert and Kimberly Huntoon, 2320 A La Costa Avenue, Carlsbad,
California 92009
Diane Rulka, Storm Management, Inc., 7920 Miramar Road, Suite
113, San Diego, California 92126 (represents La Costa de
Marbella Homeowners Association).
BACKGROUND:
DATA:
Several requests have been received by staff to install a continuous two-
way left-turn lane (2WLTL) on La Costa Avenue from the easterly side of
the commercial area located immediately east of El Camino Real and
continuing easterly to Calle Madera (see attached letters). These letters
were written as a result of concerns about the capability of safely
completing a left turn from La Costa Avenue to adjacent driveways when
stopped in the Number 1 traffic lane and encountering opposing high speed,
relatively high volume traffic. A continuous two-way left-turn lane on La
Costa Avenue has been requested.
General
Traffic studies have shown striping for a continuous two-way left-turn lane
to be an efficient and safe traffic control device. The 2WLTL did not
come into common usage until the early 1970's, however, it is purported to
have been first introduced as early as 1950 in Michigan.
Continuous two-way left-turn lanes are in use now on various street classifi-
cations in the City of Carlsbad. It provides a cost-effective method of
providing land access needs on major arterial highways. On the arterials
without a 2WLTL, midblock left turns can have a very detrimental effect on
the level of service and quality of traffic fl ow by creating delays and
forcing drivers to change lanes.
Existing Conditions
La Costa Avenue is designated a Secondary Arterial on the City of Carlsbad
Circulation Element of the General Plan from El Camino Real to Rancho
1
TRAFFIC SAFETY COfottISSION
COfottISSION REPORT OF: March 7, 1988
(Continued)
ITEM NO. 6A
Santa Fe Road. It has a curb to curb width of 64 feet within an 84 foot
right of way. Beginning at El Camino Real and continuing easterly to
Calle Madera, La Costa Avenue is striped with a double yellow centerline
that provides four (4) traffic lanes and a painted bike lane varying in
width between four (4) and ten (10) feet. Parallel parking is allowed
along some portions of the road. Left turn lanes are provided at the
intersecting streets. Numerous driveways are located on the subject
segment of La Costa Avenue, primarily on the northerly side.
Beginning at Romeria Street and continuing easterly, the road has been
painted with a continuous 2WLTL that allows only one (1) traffic lane
easterly and two (2) lanes westerly. Between Ca 11 e Madera and Romeri a
Street, two (2) lanes in each direction are provided. Bike lanes have
been striped and parallel parking permitted on the south side of La Costa
Avenue easterly of Romeria Street.
Traffic Volume Data
Traffic volumes vary along the length of La Costa Avenue. Midblock volume
data from recent counts is provided on Table 1. All volumes shown are a
total of the two-way Average Daily Traffic (ADT) on La Costa Avenue.
TABLE 1
Location
East of Commercial Area
At Nueva Castilla
At Calle Madero
At Romeria Street
At Cadencia Street
LA COSTA AVENUE TRAFFIC VOLUMES
Volume
16,627
16,005
8,477
8,842
7,043
Date Obtained
November 1987
February 1988
June 1985
May 1987
June 1987
Buildout traffic volumes have been provided to the City of Carlsbad by
SANDAG for their Series 6 projections. The projected buildout volume on
La Costa Avenue easterly of El Camino Real is 17,100 vehicles per day.
Current volumes are approaching buildout projections.
Traffic Accidents
A collision diagram is provided for reported accidents occurring on La
Costa Avenue during 1986 and 1987 between El Camino Real and Rancho Santa
Fe Road. A total of 22 reported accidents were investigated by the
Carlsbad Police Department in the past two (2) years. A review of this data
shows no discernible or consistent pattern of certain types of accidents
2
TRAFFIC SAFETY COfllISSION
COMMISSION REPORT OF: March 7, 1988
(Continued)
ITEM NO. 6A
being caused by vehicles stopped in the Number 1 lane and attempting to
complete a left turn. However, three (3) rear end accidents that occurred
are attributed to stopping and attempting to turn left into a driveway on
the opposite side of the road.
Level of Service
Roadway geometrics, traffic characteristics, side friction and traffic
volumes are some of the factors that affect the link capacity of an
arterial or collector street. Methods are provided in the Highway
Capacity Manual to determine a range of service levels for the appropriate
street classifications. These ranges are shown on Table 2 and are taken
from the "City of Carlsbad Growth Management Program Guidelines and Instruc-
tions for the Preparation of Local Facilities Management Plan Transportation
Impact Studies."
TABLE 2 LEVEL OF SERVICE (LOS) VOLUMES
Arterial
Classification Level of Service Volumes
A ft .c. Q f
4 Lane Secondary
(median, access) 20,000 23,240 26,670 30,000 33,340
4 Lane Collector
(no median , access) 16,670 19,450 22,220 25,00 27,780
2 Lane Collector
(no median , access) 10,000 11,670 13,340 15,000 16,670
A comparison of existing traffic volumes with the volumes on Table 2
indicates that La Costa Avenue is currently operating at the highest
acceptable Level of Service (A) without benefit of a raised median.
Alternatives
Due to numerous driveways located on both sides of La Costa Avenue from
the easterly side of the commercial area at El Camino Real and continuing
easterly to Calle Madera, left turns will be initiated from the Number 1
3
TRAFFIC SAFETY CotllISSION
COMMISSION REPORT OF: March 7, 1988
(Continued)
ITEM NO. 6A
traffic lane. As traffic volumes continue to increase on La Costa Avenue,
it is expected that an increasing number of conflicts will result between
stopped vehicles waiting to turn left and the through traffic in the
Number 1 lane.
A road classified as a secondary arterial in the City of Carlsbad is
generally striped with two (2), five (5) foot bikes lanes, four (4) eleven
foot traffic lanes and a 10-foot continuous two-way left-turn lane. An
example of this striping pattern is found on Mision Estancia, a designated
secondary arterial on the City of Carlsbad Circulation Element. It should
be noted that parallel parking on a secondary arterial is prohibited.
As indicated previously, La Costa Avenue is striped with a double yellow
centerline and with parking allowed in some segments. This striping
pattern could remain, however, it does not resolve the left turn/through
traffic conflict. It also does not resolve the extra wide bike lanes that
vehicles are parking within. Those bike lanes do not have sufficient
width, per CALTRANS standards, for parked vehicles and a designated bike
lane. Allowing the existing striping to remain is essentially a Do
Nothing alternative and for purposes of this report is designated Alternative
No. 1.
A second alternative, designated Alternative No. 2, would restrict left
turns on La Costa Avenue. The left turn would be prohibited by striping a
double, double yellow centerline four (4) feet wide. Four (4) traffic
lanes would be provided, including an 8-foot emergency parking/bike lane
on both sides. Parallel parking would be prohibited. Motorists would be
required to U-turn at the nearest intersection in order to return to their
destination and initiate a right turn into the driveway. Left turns from
the driveway across the double, double yellow centerline would also be
prohibited. Alternative striping patterns are indicated on Page Number 7.
Alternative No. 3 could result in the installation of continuous two-way
left turn lane ten ( 10) feet wide. This option would provide a refuge
area for left turning vehicles out of the Number 1 traffic lane. Four (4)
lanes of traffic would remain, in addition to two (2), five-foot bike
lanes. Parallel parking would be removed.
A fourth alternative striping pattern, Alternative No. 4, could be striped
that would permit parallel parking on the northerly side of La Costa
Avenue. This pattern would have one (1) eight-foot parallel parking lane
next to the curb and gutter, one (1) five-foot bike lane, two (2) twelve-
foot and two (2) eleven-foot traffic lanes and one (1) five-foot bike lane
on the southerly side of the road. The primary disadvantage of this
alternative is that left turns would continue to be made from the Number 1
traffic lane.
4
TRAFFIC SAFETY CCIIIISSION
COtl4ISSION REPORT OF: March 7, 1988
(Continued)
Construction Methods
ITEM NO. 6A
Prior to installing a new striping pattern on La Costa Avenue the existing
painted lane lines must be removed. Generally, small lengths of pavement
striping can be removed by sandblasting. However, the segment of La Costa
Avenue under consideration is too long for cost effective striping removal
by sandblasting. Installation of a slurry seal on the road would result
in the existing striping to show through the slurry seal within several
years. A confusing set of striping patterns would then be visible to the
motorist.
La Costa Avenue was overlayed with a 2-inch lift of bituminous asphalt
surfacing from El Camino Real to Rancho Santa Fe Road in two operations in
1986 and 1987. A chip seal on this segment of La Costa Avenue is tentatively
scheduled for the summer of 1988, the purpose being to extend the life of
the wearing surface on La Costa Avenue since the time of the overlay. The
chip seal installation will result in the obliteration of the existing
painted lane lines and hence, the need to re-stripe the road. Changes to
the striping pattern of La Costa Avenue should be initiated at the time
when new striping is installed.
Advantages of a Continuous 2WLTL
*
* * *
*
reduces delays, improves efficiency
increases roadway capacity
efficient method of removing left turn vehicle from the through lane
reduces certain types of accident (rear ends, sideswipes)
good public acceptance
Disadvantages of a Continuous 2WLTL
* * *
potential for misuse if used as third through lane or passing lane
can create indecision on driver behavior if unfamiliar with 2WLTL
installation results in removal of parallel parking on La Costa Avenue.
Conclusion
A review of the roadway levels of service and accident history does not
indicate that a significant safety or capacity problem exists at this time
with traffic operations on La Costa Avenue from the area east of the
commercial area easterly to Rancho Santa Fe Road. As traffic volumes
continue to increase, it is expected that more conflicts will result. The
potential for rear-end accidents, side swipe accidents and drivers swerving
to avoid vehicles stopped in the Number 1 lane continues to remain.
5
TRAFFIC SAFETY C<JIIISSION
COMMISSION REPORT OF: March 7, 1988
(Continued)
ITEM NO. 6A
Installation of a continuous 2WLTL and the removal of all parallel parking
would result in the elimination of on-street parking in the vicinity of
dwelling units where no significant on-site parking is available. The
2WLTL would allow striping of a uniform width for the bike lane where
variable widths now are striped. At this time, conflicts can occur
between bicycles and parked vehicles in a designated lane that is not wide
enough for both uses.
RECotl'IENDATION:
The Traffic Safety Coordinating Committee recommends that at the time of
installation of the chip seal on La Costa Avenue a continuous two-way
left-turn lane be striped and parallel parking removed. The limits of the
2WLTL would be from a point immediately east of the commercial area on La
Costa Avenue easterly to the existing two-way left turn lane at Calle Madera.
NECESSARY CITY COUNCIL ACTION:
No City Council action is required to change the striping configuration on
La Costa Avenue. However, the Traffic Safety Coordinating Committee
recommends that any striping changes proposed be discussed at a City
Council meeting as an informational item before being implemented on La Costa
Avenue and that the parking restriction be formalized by City Council
adoption of an ordinance designating the NO PARKING zone.
6
LEFT TURN PROHIBITED
EMERGENCY PARKING-
a' 11' I 11' 11' 8'
I
ALTERNATIVE 2
LEFT TURN OK
PARKING ON 1 SIDE
8'5 12'1 11' 1 1' I 12' 5'
ALTERNATIVE 4
7
2-WAY LEFT TURN LANE
PARKING PROHIBITED
I I
5, 11' I 11 •
1
1 a ,
1
11' I 11' 5,
ALTERNATIVE 3
l OCATIOH A'--i!!C"~s--COLLISIO N DIAGR A .... -::: .,.-4 ~,,,,-re, .J:::>e: .-,/
CITY OF CARL SBA D
T RAFFIC ENGIN~ERING SECTION
NO. ~y TY PE
TIAI TOT4l ,10 ,. DAM A G I I H JUIY
\\
c;,v-...,.,,-\~°\'"(" 105Z.:,
l'Z.-\7-e,7 04!0
€:~-\~.,::,.._~ '?O\C\,
ff!>-Z.."1-e,7 l C.. ~ -z.4-,-<-,~,c.,,_--c-,oe.,4-,~-z~-$.., ,-z.~~'::>
~-?'7 o,e,eo
\-7-'c? o-=,,: ~o
e:~-\~A-~ z ~ -e> 7
3-z._~ • 07 1-z.·. -so
pv,....,,,., z.z.s o
~-Z.Z-· '87 01: ~z.
~7';7-11'•.).A.~ I -Z.""l~
,z-,~-e,7 0 0\!00
7
C..C,?O
oe:oo
to 1'"7,
OS:3O
p.. ~\.; (;;'\
CSJ<if° 3. V
s 0
~6 v.../? Kc::>\\ov-c...<
\~~-.JV ',/
,A./e!, V'v'-::, F\..,..
vopc.~ o -~ ~
E:.."e, 1-E.~~ ~-~:!It/I("\ L-~e,.
\~V'<
\/',./~ R-~ =YP-.:: ~-Q'
~~'-''<'
y....,'t-3 ~ooc::.o\\\"7\(..)
?v-~"<-,--Y 'D-~4.-'
v,....-e. '""'" ,...:«..A
~"?~~ 17....,.........._.a.,.c..,.,
e.e, \ °' ~C> o .::=.,.c, \ \' '=7\<>N
-Pv-~...-.c D o.~~
,~ ;:\....-~
°R-c:::>P<!--<<' Dc::i..~c:a.~
1"
5'.
VEH. MOVING AHEAD
((( ► YE H. BACKING UP
----• PEDESTRIAN
TRAIN
c::;> PAR KED VEHICLE
□ FIXEO OIJECT
0 PROPE"TY DAMAGE
® INJURY ACCIO£NT • FAT>.L ACCIDENT
ONLY
.J
.J
LEGEND
HEAD-ON
HEAD· ON SIDESWIPE
REA" ENO
OVERTAKING SIC[ SWIPE
RIGHT ANGLE
A~PROACH TURN
OVERTAt<INO TURN
OUT OF CONTROL
VEHICL[ TURNED OVE".
llOHT
s
~
CO~ST CONSTRUCTION ZONE
CPO DRIVER ~YSICAL DEFECT
ov DEFECTIVE VEHtCLE
E S EXC(S5 SPHO
FTC FOLLOWING TOO CLOSE
~BO HAO BEEN DRINKING
H·II HIT ANO HUN
ILC II.IPROPE R L AN E CHANGE
IP IMPROPE R PASSINO
IT II.IPROf>(" TU RN
IHATT INATTENTION
llt/C UOTORCYCL(
RSS RAN STCP SIGH OR SIGNAL
SFP STOPPED 0~ St.OWING FOIi
VO VISIBILITY OASTRu,:T[O
v""' Vll"'II & Trf"'il o,,.. .... ,. r,# -·~
WI I
u.
,I\
rt
D(Q[STRIAN
COLLISION D l AG n ~ U.,
CITY OF CA RLS Bf\D
TRAFFIC ENGIN=ERIN G SECT ION
OIAWN
IY
,,<\ _,..q.,_~_,.-
~~/~G) ,e,.,/
NO. ACCIDENTS ~y TYPE
IOUL ,oo,. OAMACI IN JUIT llOMI D A. II(
\ \
VEH. IICOVING AHEAD
( (( ► V(H. 8ACKING UI'
---♦ PEDESTRIAN
TRAIN
c::> PARKED VEHICLE
□ FIX(O OI JECT
0 PROPERTY 0A1,1AG( ONLY
® INJURY Ac::10£111'
• FATAL ACCIDENT
g D
a...-
E=-~ i;:::::::-1-.c::~
"Pv~v<y -C::,~~c.-
~
◄
--,...0...-
►l ~ ~ ~
~ Du--
...,....,e,. ""10 C:::..C., l \ ";;,l~
\~~vYY
LEG END
H(AO•ON
HEAO·ON SIOESWIPE
REAR ENO
OVERTAKING SIOCSWIP(
RIGHT ANGLE
A>'PIIOACH TURN
OV(RTAKINO TURN
OUT o, CONTROL
VEHICI.[ TURNED OVER
\D l
CON ST CONSTRUCTION ZONE
Of'O ORIV(R P><YSIC.!.L OEJ"ECT
CV DEFECTIVE VEH1CL!
ES EXCESS SP(EO
f'TC FOLLOWl "G TOO CLOSE
"BO HAO B(EN ORINKINO
H•R HIT ANO "UN
11.C IMPROPER LAN( CHANGE
IP ll,IPROP(R PAS~INO
IT 11,1PROP(R TURN
INATT INATT(NTION
lol/C MOTORC'YCI..E
ASS RAN STCP SIGN OR SIGNAL
SF P' STOPP(O OR 5'..0WING FOA
VO VISIOILIT'Y OAS ~""'~~co
\
u.
,I\
rt
OtC(~T~I A
Ro b t:' c t T . J ,.:, h r, so n , J c . • t' . f .
~·,1.11c 1.p .:::,1 C .1.·1 LL ~~c,c1 ·Lc,ee c
E:n ,.Ji.1,.,:-tc-c 1.n y Dt:·pai· t r,,ent
~0 75 La~ Palmas Dci.ve
Pee t he request of Mr. Pat O 'Day o f the T r affic Safety
Commission, I am documenting the observations and possible
solutions to a danger ous traffic/safety situation on La Costa
Avenue.
My wife and I recently purchased a condominium at 2320 ~Aw La
Costa Ave nue. Our home is situated approximately 800 yards
east of El Camino Real on the north side of La Costa Avenue .
Ingress/Egress from our project to La Costa Avenue is very
dangerous; especially if one is turning north into the
project from the west. There is no turn lane available.
During c ush hour s one 1s often required to wait, stationary,
in tht=< left lane while on-coming traffic clears for safe
entry. The danger l i es in the vulnerability of the
stationary, left-turning vehicle to cars also traveling from
the west at speeds near or above the posted speed limit of 45
Mph. (Someti mes greatly exceeding the limit>.
We sugges t three solutions to reduce this hazard which we
feel wil l meet the traffic flow requirements and limit
expenditures.
A) Provide a safe, turn-lane in the middle of La
Costa Avenue similar to that provided on La Co~ta
Avenue east of our home. We suggest a turn lane
bounded by solid yellow-broken stripes with a
single traffic lane east and west. <This should
be continuous from El Camino Real to help
eleviete a similar problem immediately east of El
Camino Real on La Costa Avenue as cars turn into
the shopping center, water district, school, etc.
while traveling east).
B> Continue the 35 Mph speed limit zone through the
residential areas.
C> Eliminate confusion among the residents
concerning parking in the bike lane areas by the
posting of signs and/or notices of parking
r.a-strictions, if any.
I write this letter with the hope t hat immediate atte,1 t1.on
can be brought to this matter. My wife nearly missed a
accident the other day; I s peculate that i t is only a matt e r
o f time before a s erious a ccident o ccuc s . I would apprec i ~te
it Lf y o u would inform me of further meetings, etc. 1.n ocd e r
t ha t I ,.-, a y ass 1. s t i n t· e d u c 1. 11 g t h i :::. danger o us s 1. t u a t 1 on .
Robert P.
2.J20 A L a
r:::a 1· l ::::bad,
Huntoon
C,.:i s ta Av e nue
C A '320 0 '3
:copy Pat O'Day
City of Carls bad
Attn : Ci ty Manager
t:::::OO Elm Ave.
~ar l sbad, CA 92008
D~d , C tty Manager:
Septembe1· 2:J,
S e veral ~onths ago my husband and I sent the enclose d letter
to t ht::' Eng i nee i· 1 n g De pa r t men t , C i t y of Car l s bad . A t t hat
ti me we fel t that the r e was a serious safety threat to
persons liv ing on La Costa Ave. T his threat being from
motorists t raveling well beyond the posted speed limits as
well as the lack of safe turn lanes. Since that time there
have been near misses much like the one I will describe.
Mrs. Gagliardi,who lives in our complex was stopped 9-23-87
waiting to turn into our drive way. A vehicle came up
quickly behind her with another vehicle following. The first
car swerved out in front of the second vehicle to avoid rear
ending Mrs. Gagliardi. This sudden movement caused the
second vehicle to loose a tire, narrowly avoiding a serious
collision. Must someone be seriously injured or possibly
kil l ed befo re action ls taken. I would suggest narrowing
the bike lanes and making them "no parking." This would
allow enough room to repaint the street with a center turn
lane. The bike lanes as they are now pose a safety problem.
Motorists park their cars in the bike lane leaving very
little spac e for bikes to pass. This is surmounted by the
fact that golf carts are forced into the street because of
the par ked cars. We did receive a response from Mr . Johnson
and we appreciate his taking the time to answer. He briefly
stated that there was no~ enough use for a turn lane in front
of our complex and the speed limit was allowable up to 54
m.p.h. The Carlsbad Police Department has been good about
checking th• traffic for speeding offenders. We would like
their conti nued efforts as well as your assistance in this
matter.
Sincerely,
¥uuu?-4£-j>,/~/-)
Kimberly Ring Huntoon
2320 A La Costa Ave.
Carlsbad, CA 92009
(61'3 ) 943-0777
Strom
Management. lne.
Oc tober JO , 1987
City of Ca rlsb ad
2075 Las Pa l mas Dr ive
Ca rlsbad, CA 92 00°
Re : 2401-2433 La Co st3 Avenue
Dea r Sir :
La Costa de Marbe lla Hom eow ners
Traff ic ha s been steadil y
now e xtreme l y hazardous and
This l etter is writt e n on be half o f the
Association consis ting of 58 units .
increasing a long La Co st a Avenue . I t is
difficult to turn a t the driveway to our
that a turn l a ne be considered .
Association. We a r e asking
Plea se ca ll me to discuss a ny a dditiona l deta ils or pr ocedure .
Since r e l y ,
Diane Rulka
Ma nagement Consult a nt
cc : Board o f Directors
70?n Mirnmm r.>nnrl c:;11itA 11 .~ • t:;nn niAnn r.nlifnrnin 0?1?6 • (6101 578-8220
Dr. Waldemar Brehm
2424 La Costa Avenue
Carlsbad, CA 92008
February 22, 1988
Office of the City Enquirer
2075 Las Palmas Drive
Carlsbad, CA 97009
C/0 Mr. Mike Shirey
Dear Sir:
1-'i:-..
.:.... l:f .. '-',
~ ,J
We are in receipt of your letter of February 8, 1988, describing the proposed plan
for changing the laws on La Costa A venue, east of El Camino Real.
We strongly oppose this plan as it will entirely eliminate our parking space for our
family and friends. We have only two parking spaces in our driveway. Also we have
a 35 foot motorhome and we must use curbside parking for loading and unloading the
Recreational Vehicle. Any restriction on curbside parking would adversely affect our
property value! To eliminate curbside parking would create an extreme hardship for
us.
We have lived here for ten years and have found no real problem in making a left
turn into our property_!!:_ the left turn signal is used as it is supposed to be used. If
the speed limit in both directions was enforced, much of this problem would be elimin-
ated. We have lost our mail box which is mounted on a 4x4 brick block, three times
to drivers speeding down La Costa A venue and losing control of their vehicles. Also
the "No Trucks" on La Costa Avenue should be enforced. They create a back up of
traffic problems in both directions, especially during busy hours, which only magnifies
any problems which may already exist.
We hope you will give serious thought to alternative solutions and not take our
curbside parking from us -now or ever!
Sincerely yours,
~~ d "'~
Waldemar Brehm, D.D.S.
CB:jb