HomeMy WebLinkAboutAgenda Bill 7.A-Attch1 06/07/2004Prepared for,
Susan Lackie, City of Petaluma
Technical Menwrandurn
May 24, 2004
Prepared By:
Patrick J. Flynn, PE, HDR` Engineering, Inc. r .
James Labanowski, PE, HDR Engineering, Inc.
Matthew AICR,'Fehr £t Peers Associates, Inc
Matt Haynes, PE, Fehr tt Peers Associates, Inc.
Introduction
At the request of Mr. Michael Bierman, City Manager, and Ms. Susan Lackie, Project Manager
for the City of Petaluma, Fehr & Peers (FPA) and HDR conducted a comparison of several
alternatives for cross town mobility enhancements, focusing on potential changes to Corona
Road. Fehr &- Peers developed travel forecasts to assess travel demand for the alternatives and
level of congestion relief afforded to existing arterials such as Washington Street and Old
Redwood Highway.
This technical memorandum includes a description of "the altertiatives developed through the
initial screening process with the City and the FPA/HDR team, as well as conceptual geometric.
drawings and'e'stimated construction costs for the various alternatives. This memo includes a
matrix~ °identifying evaluation criteria used for the screening-of interchange alternatives and a
preliminary: evaluation of each of the alternatives. This memol also outlines possible issues
Caltrans project;engineers may raise with.regards to these alternatives.
C
City of Petaluma
Corona Interchange Alternatives
May 24, 2004
Technical Memorandum
•
Corona- Road Interchange Alternatives
To simplify the analysis process and provide useful information for decision- makers to
understand the implications of each scenario,, the -analysis is structured into .two processes. The
interchange configuration options are evaluated immediately below; including the no . project
scenario. In the subsequent section, the interchange configuration and intersection control
Options are evaluated according to their transportation ,operations.
Base Year 'Conditions and Additional Land Use Changes
The transportation analysis was conducted using ,.Base Year existing conditions from the City's
transportation model. City staff requested the following projects be; :included with the
transportation analysis of each scenario-.
Project 1. Petaluma Village Marketplace Outlet'Mall Expansion
Project 2. Petaluma Valley Plaza
Proj ectr 3. Oak Creek Apartments
Traffic from these projects was added to Base Year conditions using the City's TransCAD r
travel demand forecasting model. This model was developed for the General, Plan effort and
underwent a igorous validation process.
Interchange Alternatives
The consensus between the City staff ,an_d :HDR/FPA team on reasonable alternatives are the
following;
Scenario 1.
Rainier Alternative
Scenario 2.
New Corona Alternative
Scenario 3.
Original Corona. EIR.confguration
Scenario 4.
No Project Alternative
These scenarios are described in detail beginning on Page 4
The table on Page 3 provides' a relative comparison -of the alternatives Build alternatives at
Corona Road and Rainier Avenue would require a California Department of Transportation
(Caltrans) Exception to the Mandatory Design Standard for interchange spacing. An
interchange at Corona Road would be less than the required one mile distance from the
interchange at' Old Redwood Highway, and an interchange at Rainier Avenue, would, be less �.
than one mile from the existing Washington Street interchange: This Design Exception would
need to be. obtained prior to initiation of 'a Project Study Report.
City of Petaluma 2
Corona interchange Alternatives May =24,,,2004
Technical Memorandum
0
Build alternatives at Corona :Road will likely require replacing the existing structure at a
considerable construction expense. Auxiliary lanes will be necessary between this interchange
and the one at Old Redwood Highway due to the close spacing. Significant right -of -way
impact should also be expected for any build alternative because of the development that has
occurred in proximity to the Corona Road overcrossing.
City of Petaluma
Corona Interchange Alternatives
3
May 24, 2004
T7P
ALTERNATIVES EVALUATION MATRIX
Technical Memorandum
*Estimated construction cost not include costs for land acquisition and relocations.
City of Petaluma 4
Corona lnterchange,Atternatives May
Tra. IV;* 'M A
bapf"i
( Ac ceptanc es
W
rm le i
T) C
wo HE
Cost
Scenario
Rainier
(Alternative I.,
South
h'
Alignment)
0 .76
New EIR with
Miti g btions:
Visual Enhancements
Soundall
ws
Tr
-ee Replacer
Replacement
Hydraulic,Study
Socio-economic
Historical
Significant on East
side of Hwy 101
(13 Properties ,l I 28
relocation) also 1.
acres iri floodplain,
034 acres An riparian
zones
Moderate:
Cha leride to
get approval I of
interchange
exception
Moderate
Challenge
$12A Million
($73 Million
uner , plus
u
p
$ 4.8'Million river
crossing)
crossing)
Scenario. 2
New EIR With
New
Configuration
(L-8
0.42
Mitigations:
Visual Enhancenferits
Soundwalls
Tree Replacement
Sig
Sw, and
Quadrants:
-8.5 Acres
ChallengeAo
get,approval of
interchange
Moderate
Challenge
$13.1 Million
Interchange)
H c
yorauli Stadq�
rope
- 5 P tties
spacing design
. . . . . . . . . . . . . . . .
Socio-economic
Historical
-3 Relocations
exception
'Scenario:3
New EIRE With
Qriginal,EIR
'Configuration
0.42 1
Mitigations:
Visubl'Ehhahcements
Soundwalls
Tree Replacement
Hydraulic Study
Socio-economic
Historical
Sign in NW,
SW, and SE
Quadrants:
-7.3 Acres
-6 Properties
-3 Relocations
Not Likely
Approvable:
Numerous
design
exceptions
required
Moderate
Challenge
$11.7 Million
Scenario 4
as
No Build
0.21
None
None
N/A
N/A
$0
Notes: rTrans portation utility1s rated on a scale of ze-rb,( 1 0) Ao one: (1 w - ith-,zero representing the leastLutility and one representing the most utility. See the
Transportation A details on the transportation utility-rating.
*Estimated construction cost not include costs for land acquisition and relocations.
City of Petaluma 4
Corona lnterchange,Atternatives May
m
rp
Scenario 1= Rainier Alternative
Technical Memorandum
This alternative was developed as the preferred alternative for Rainier in the 1994 adopted EIR
and refined in the :Cross Town..Mobility Enhancement Alternatives report prepared in December
2003. The .Rainier ,Avenue connector follows the -City's adopted precise plan alignment. The
geometries] ayout is shown on Exhibit 1 The significant difference between this current layout
and the 1994. configuration is. that Rainier Avenue is not elevated thereby eliminating a major
structure over the freeway. In 2 dollars, the estimated construction cost for the original
configuration going over the freeway was $24 million. The estimated cost for the alternative
where Rainier Avenue is constructed on existing grades is $7.3 million. An elevated structure
over the Petaluma.River and the railroad tracks is also assumed at a cost of $4.8 million.
The Rainier "Southern° Alignment connection, to Petaluma Boulevard was used for the
transportation analysis. This alignment has a higher transportation utility and was forecast to
attract more vehicle trips than a north alignment in the Cross Town Mobility Enhancement
Alternatives report.
From a transportation utility perspective, the Rainier interchange scenario performs better than
both Corona interchange alternatives and. the No' Project alternative. This means that of the
studied scenarios, a connector ' at "Rainier would best facilitate cross -town travel and provide
relief to currently congested cross• town roadways. It does, however -, also introduce more
additional traffic on feeder, routes to cross' town ' roadways. On a scale of zero to one, the
overall transportation utility of the Rainier scenario is 0.76.
City of Petaluma 5
Corona Interchange Alternatives May 24, 2004
Me00WELL BLVD -:
i�
e
eocee aaan : a•�e ®m
2165 tro >olnf "RO
1.11. 300
Follw 7CA 95630
19161 a17-4 too.
SCALE 7"=400'
W
W'
4
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Scenario 2= New Rodd fnterchange.Co
nfiguration
Technical Memorandum
This two- quadrant cloverleaf alternative, is the most likely design to fit the existing conditions
at the Corona Road overcrossing. Right -of -way. impacts to an adjacent mobile home park and
car dealership would .make. any four - quadrant alternative difficult and costly. The geometric
layout is shown on Exhibit 2. Although this alternative can be designed to meet Caltrans
standards, .significant right -of impacts will remain. Sizeable retaining walls would be
required 'to limit the impact to the dealership located in the northwest quadrant. In addition,
existing access roads to several .properties adjacent to the interchange would need to be
relocated
To accommodate. expected traffic projections, the, structure for this alternative would need to be
one lane wider than the configuration proposed in the ,1994 EIR. The intersection of Industrial
Avenue with., Corona Road, would also need to .be relocated to the' west in order to comply with
Caltrans intersection. spacing requirements and to Prevent 'vehicle queues from spilling into
adjacent :intersections. The relocation of Industrial Avenue is constrained by the planned
Denman Ranch Flood Reduction Project at this location, for which the City recently purchased
the property. This relocation would require reimbursement to the funding agency at a
considerable cost to the City. If Industrial Avenue is not relocated, the interchange project
would need approval of another design exception by Caltrans.
i
U
The transportation utility of the Corona configuration is less than for the Rainier configuration.
Based on the transportation analysis, many of the trips a Corona interchange attracts are from
the Redwood Highway interchange, leaving Redwood. Highway underutilized. There is
substantially less, congestion relief at Washington- Streetwith a Corona Interchange than with a
Rainier Interchange. On a scale of zero to one, the:, transportation utility of the New Corona
Interchange scenario is 0.42.
City of Petaluma
Corona Interchange Alternatives
7
May.24, 2004
� � •
Technical Memorandum.
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Scenario 3 — Original'E1R Configuration
This configuration was developed as an alternative to the Rainier Avenue interchange in the
1994 adopted EIR. The geometric layout is shown in Exhibit 3..
Planning, approving, designing, and constructing an interchange in this configuration would
have considerable challenges. Numerous Caltrans exceptions to design standards would be
required for non- compliance with geometric requirements. Additionally, locating the ramp
intersection opposite the'local road (Industrial Avenue) would not comply with the Caltrans
standard for 'access"' control. Right -of -way requirements would significantly impact
commercial /indu"strial properties in both the northeast'and northwest quadrant and the livestock
auction yard in the southwest quadrant.
The transportation- utility of the Corona `EIR configuration is less than for the Rainier
configuration. While interchanges at Rainier Avenue and Corona Road attract roughly equal
numbers of vehicle trips, many of the trips a Corona interchange attracts are from the Redwood
Highway interchange, which results in Redwood Highway being underutilized. A Corona
interchange also provides' substantially less congestion relief at the Washington Street
interchange. On a scale of zero to one,. the 'transportation utility' of the Corona EIR scenario is
0.42.
City of Petaluma 9
Corona Intercfiange Alternatives May 24, 2004
� � •
1 F- DR
Technical Meffiwandum
Scenario 4-- No Proiect
There are no assumed improvements to any roadways under this alternative. This alternative
would l maintain the existing two-lane rural overcrossing at Corona Road. The existing facility
has four-foot,sidewalks to accommodate Pedestrians,- but only a small shoulder (1.5 feet) for
bicycles. This alternative would require no additional night-of-way, have no environmental
impact, and no associated construction cost.
Maintaining the existing overcrossing from a traffic- standpoint would provide no relief to
existing cross town connectors. This scenario has the lowest transportation utility of the
I
studied alternatives. On a scale of zero to one, the transportation utility of the No Project
scenario is 021
•
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City of Petaluma I I
Corona Interchange Alternatives May 24, 2004
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Operations of Freeway Interchanges
technical Memorandum
This section describes the transportation operations results of the interchange scenarios.
Results are: described 'in greater detail in Appendix B of the Transportation Technical
Appendix.
Scenario 1 - Rainier Configuration
This alternative performs .well under the existing traffic conditions plus the three new projects.
Intersection levels of service and queue lengths are more acceptable under this scenario than
the Corona Road scenarios despite the fact that intersection traffic volumes are projected to be
similar in magnitude.
Scenario 2 -New' Corona Road Configuration
This alternative was developed using the results of the initial modeling effort to determine the
precise roadway geometries and intersection layouts. The Scenario 2 configuration performs
well under existing traffic conditions plus the three new projects. Intersection levels of service
and queue backups are acceptable under this scenario.
Scenario 3 - Original EIR Configuration
The Scenario 3 configuration has several issues in terms of traffic operations, making its
transportation operations rate as unacceptable according to the rating system described in the
Appendix. Transportation ,analysis conducted as part of this report indicate there will be
substantial numbers of vehicles making left turns onto Highway 101 from Corona Road.
However, the EIR configuration provides single left turn lanes' with short turn- pocket lengths,
which in turn affects intersection levels of service and vehicle queuing. Both Highway 101
ramp intersections perforin'.worse under the EIR configuration than under the new Corona Road
Interchange configuration.
City, of Petaluma 13
Corona Interchange Alternatives May 24, 2004
Corona Road: Interchange'Evaluation
Transportation Technical Appendix
May 24, 2004
TABLE ,OF CONTENTS
APPENDIKA TRANSPORTATION UTILITY ANALYSIS, ............................. ......................... 1
AP- TRANSPORTATION OPERATIONS, ANALY81S ............... ...... ..............:...............4
APPENDD(c LEVEL OF SERV QUEUE: LENGTH PRINTOUTS.. ... ......... ............. 8
•
T
F L 1 I P L L 1'1.s
TRANSPORTATION CO'NSULTANTS
Pagel
f p
TABLE OF CONTENTS
F- I SIT
Corona Road Interchange Evaluation
Transportation Technical Appendix
May 24, 2004
APPENDIX A TRANSPORTATION UTILITY ANALYSIS ...................................... ..............................1
APPENDIX B TRANSPORTATION OPERATIONS ANALYSIS .......................... ..............................4
APPENDIX C LEVEL OF SERVICE-AND QUEUE LENGTH PRINTOUTS ......... ..............................8
.0
FEH.R. & PFER.S
TRANSPORTATION CONSULTANTS
Page
Corona Road Interchange Evaluation
Transportation Technical Appendix
May 24, 2004
APPENDIX,A
TRANSPORTATION UTILITY ANALYSIS
Utility is a term intended to describeithe benefits or disbenefits, Of, a transportation option. Utility is
measured through.. a combination of'factors consisting of average trip length, travel demand on the
potential new roadway, congestion relief afforded to other cross -town connectors, and congestion
introduced to feeders to the potential new cross-town routes. These factors are combined to form an
overall utility assessment. Utility is intended to. measure -only changes to the circulation system, so all
travel forecasting has been conducted using the land use - assumptions — the 2001 Base Year
conditions with the following three projects:
Petaluma- Village Premium Outlets: For purposes of the traffic model, this project was
assumed to add approximately 250,000 square'feet of shopping center / retail use adjacent
to the existing, outlets.
Petaluma Valley Plaza: 346,000 square feet of shopping center use and 52,000 square feet
of,strip commercial use near the' intersection of North McDowell and Rainier Avenue were
assumed-for the modeling' effort.
Oak Creek Apartments: This projecfi.was assumed to include 312 apartment units with
connections to Graylawn Avenue "and Shasta Avenue.
While the magnitude of the above three projects may change to be less than shown, a "worst case"
scenario was,assumed for modeling'purposes.
Indexing
One method of combining, measures that are -taken through dissimilar processes is to index the
results to a common scale;;, This'analysis is prepared using - indices, with each measure of
effectiveness rated on a scale from zero (0) to one (1.00): Cher alternative that performs worst on a
particular measure of effectiveness receives. a zero; and the a [tern ative that. performs the best
receives a one. The other,alternatives are indexed on a constant scale between zero and one.
An overall utility is determined by averaging indices for each measure 'across, alternatives. Because
the overall utility is an. average'of "the indices for each measure of effectiveness, it is possible that the
worst alternatives.will have an average utility of greater than zero.
Measures.of Effectiveness
Selecting appropriate measures of effectiveness is likely the most critical step,', in preparing an
evaluation of alternatives. The analysis of utility combines four key mea§uresl of effectiveness that.
effectiveness, the waypn t which it benefits
s measured well as
and the importance ne measures of
of the wide:ran a of o project.
p measure are described in
Table A-1.
,Corona Results
Table -2 summarizes' °fhe results ofithe utility analysis for the fourscenarios. This analysis does not
consider the two Corona Road interchange configuration options separately, only the location of an
F E I- R. & S E E R S,
TRANSPORTATION CONSULTANTS Page
CoronaaRoad Interchange Evaluation
Transportation. TechnicalAppendix
May 24, 2004
interchange at Corona Road or RairiierAvenue as compared with a; no proj'ecValterriative. According
to the measures of effectiveness in Table A-2, the two interchange options at Corona. Road would be
equal.
The two Corona Road interchange' options are evaluated and compared to,,;one another°via a
separate set of measures described in Appendix B.
'Table A -1
Measure of Utility
Ex lanation of Measures of Effectiveness
Measure of
Measurement Procedure
Significance
Effectiveness
Route Directness_
Route ° directness is measured by thwaverage
Route directness is,important because
vehicle trip length, which -;is a`functionof the total
it measures whether the location of an
vehicle miles of'fravel: and the number of'vehicle
interchange facilitates travel where
trips in the model. Although this measure
travel demand; is most needed:
;captures.all trips in Petaluma (not
using .Corona or Rainier,),it addresses, overall
route, directness. Alternativesltfiat'would,
-
facilitate travel on the most direct;path of travel
(i.e., with the least:route diversion) will have
lower aVerage4rip lengths.
Daily Travel'
Daily travel'demand measures the,amount of
Daily, travel demand is important
Demand
demand for cross -town connector options at
because it measures�whether there is
Corona and Rainier, It is a prediciion•of the
sufficient demand to justify
number of daily vehicle trips that would be
construction of a potential`new
facilitated liy the connector.
connector. Unlike rout& directness, it.
does not, distinguish, Whether the route_
taken is convenient, only'whether
'Afforded
vehicles use connector:,
Relief .to
Relief is measured as he amount,of'daily'travel
-
Theassumption and oftentimes
n
on her cross= towrnconnectors.
justification for constr9ctmg a new
Congested
o
Alternatives that,score well.on this assessment
�mhotle
roadway or °interchan a is that it will'
Roadways,
are that lower the travel demand on
relieve congestion on -other routes
adjacent cross -town connector roadways. For
where capacity entianceinents' ar`e
the sfudies alternatives ; these , are , Washington.
either infeasible or undesirable. This,
Street, ,Lakeville Highway and Redwood
tool measures whether relief`,is
Highway. Win important to note that onlycross=
afforded by`interchange alternatives at
town connectorsswith volume -to- capacity ratios
Corona cr Rainier -:
of 1.0 or were considered`in this
evaluation.
Congestion
Congestion'introd'uced on feeder routes is
A negative impact!of•,new or °.widened;
Introduced on
measured through daily travel demand on
roadways can be increased congestion
Feeders
congested routes feeding the new connector
on.roadways ahat�feed the new•roadt ,
roadways. Congested' foutes,are considered
This measuFerrienf assesses the
those with volume -to- capacity ratios of 1.0 or
relative traffic addition on congested
greater.
connector feeders.
FE7 p", c5 PEERS
T'RA CONSULTANTS
Page 2
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Table A -2
Measure of Utility
Corona Alternatives Comparison
Measure Scenario 1: Scenarios 2,3 Corona Scenario 4: No Project
Indicator #1, Route. Directness Measured b' Average Trip. Length
Vehicle Miles of Travel in Model
1
1,444,660
1,445,909
Vehicle Trips in Model
415,409
415409
415,409
Avera e Trip Length in miles
3.46
3:48
3.48
Indexed Average Trip Length
1.00
017
0.00
Indicator #2 Overall Dail ", Travel Demand on Corona and Rainier, vehicle trips
Corona North of US 101
13;469
32;765
18,178
Corona (Overpass of US 101,
13,469
38,607
18,178
Corona' South of US'101
13,469
32,277
18,178
Rainier North of US 101
32;596
0
0
Rainier Over" ass of US 101
35948
0
0
Rainier South of US 101
36;153
0,
0
Indexed Travel Demand on Corona / Rainier
1 ;00
0.54
0.00
Indicator - Relief,:Afforded;to Cross -Town Con ested.Roadwa s
Washington : North of;US 101
32;717
44,419
47,288
Washington (Overpass of US 101
27,929
37,425
42;216
Washington r South of'US 101
24;786
35,071
37,906'
Percentage of,Hi hest Value
0:33
0,08
0.00
Indexed To Lowest Value
1:00
0:25
0.00
Redwood,H NorthOUS'101
31,489 "
27,072
36,929
Redwood H Over ass of US 101
22,152'
16,570
28,436
Redwood H South of US 101
19;930'
19,264
25,365
Percentage of'Highest Value
0.19
0.31
0.00
Indexed To Lowest Value
0:62
1.00
0.00
Avera a Indexed Cross -Town Congestion Relief 0.82 _. 0.51' 0.00
• ..lhdicator#4a Congestion Introducted on „Corona Feeders
Petaluma Blvd North of Corona
14,145
15;
18,252
Petaluma Blvd South of Corona
2,
132,641
1 27,504
Indexed to Lowest Value
F 1.00
0:00
1 0.21
Highway 101 NB South of Corona
50,797
46
46,286
Highway 101 NB North of Corona
50,797
52
46,286
Highway 101 SB North of Corona
43,698
41,004
41,999
Highway 101 SB South of Corona
43,698
43,289
41,999
Indexed to Lowest Value
0.00
0.39
1.00
McDowell Avenue North of Corona ".
23;442
1 22,362,
24,755
McDowell Avenue South of Corona
18,888
21,217
20,454
Indexed to Lowest Value _
1:00
0.57
0:00
IAverage Indexed Congestion Introduced' (Corona)+ 1 0:29 0.35 0.70
Indicator,#4b•- Con" estion Introducted on Rainier'Feeders
Petaluma'; Blvd North ofRaimer7Shasta
19;244
31,120
28;841
Petaluma "Blvd; Southof•Rainier /Shasta
40,184
30,667
28;457.
Indexed to Lowest Value
0.53
0.00
1:00
Highway 101 "NB" Soutn'of Rainier
_ 48,002
46;878
46;286
Highway 101 N8 North,:of_Rainidlr
50;•797
.46;878'
46;286
Highway 101 SB North of Rainier
43,698
43;289'
41;999
Highway 101`SB Soutli:of;Rainier
43;936
43;289 "'
41,999'
Indexed to Lowest Value"
0.00
0.62
1:00
McDowell Avenue North of Rainier'
- 28,689
22;832
22,895
McDowell Avenue South of Rainier
21,248
19,493!'
19,935
Indexed to LowestValue
0.00
1.00
0.93
- - - -- i o:oI+• I u as 1
Avera a Indexed Congestion Introduced 0.20 0.45 0.84
Average of Alllndicators" 0.76 0.42 0.21
Corona Road. Interchange' Evaluation
Transportation Technical Appendix
May 24,:.2004
APPENDIX B
TRANSPORTATION OPERAT IONS ;ANALYSIS
Transportation operation - - s are intended to measure the functional quality of:the'potential cross town
roadways.: The interchange configuration and intersection control options for the Corona Road
alternatives, are compared with each other "and with the Rainier Avenue intersections.
The.op�&rations analyses are based on volume projections from Petaluma's new TranSCAD traffic.
model. Based on these volume projections; Fehr & Peers prepared a •Synchro network to analyze
intersection operations atkey intersections for the Base. Year (plus the three projects mentioned
above) AM and PM peak hour conditions.
stud`y'Intersections
Transportation operations.analysis focuses on. a few key'intersections for each cross -town connector
option. These are:
Corona Road
Corona Road @ Petaluma Boulevard North
Corona Road ,@ Highway 1'01 Northbound. Ramps
Corona. Road @ Highway 101 Southbound Ramps
Corona Road @ North McDowell, Boulevard
Rainier Avenue
Corona' Road @ Petalum :Boulevard `Nort h
Rainier Avenue .@ Highway'161 Northbound Ramps
Rainier Avenue @Highway: 101 Southbound Ramps
Corona. Road @;North'McDowell Boulevard,
Measures of"Effectiveness
The operations assessment is a tiered' assessment of overall'tran 'sportation: contlitions. The output of
th'is,assessment process isa conclu on whether' the, option operates "acceptably," "marginally,`` or
"unacceptably." Acceptable operations are considered to be, any level of operations where .
anticipated travel' demand can be accommodated. 'It,is;importantto note thoughEthe °city
maintains a level of. service `(LOS) "C''operations standards (Le. , it i' ;,the City's objective that all
intersections doerate,at LOS C or better conditions),'this: analysis permits COS D and/or conditions
within'the "acceptable" range. "Marginal" conditions are those where traffic flow is ;accommodated
durin 9 _.
overcapacity c ^nd, -ditto . ns, U ut where f luctuations in traffic demand may result' in short periods of
ayera 9
a conditio
nacc p"ble" conditions are those where traffic . demand exceeds
capacity at an isolated,intersection and /or'queues'from one intersection are I anticipated'to' reach an
adjacent intersection resulting. in a: system wide failure..
The tiered assessment of traffic operations was conducted according to the following steps:
F,Et= r. & PFERs
T,R'ANSPOIRSA'TJON CONSULTANTS
Page ,4
fp Corona Road Interchange Evaluation
Transportation Technical Appendix
May 24, 2004
1. Isolated intersection analysis Key study intersections were assessed for volume -to- capacity
(V /C) ratio and average delay. Potential results are:
a. Acceptable = ;If'V /C ratios (average for all approaches) ;are less than 0.95 (the
intersection has sufficient capacity to carry hourly demand) and average delays are
consistent with LOS E(or better conditions
b. Marginal If average delays are consistent with LOS' E or better conditions and the
average WC ratio Js less than 1.20
c. Unacceptable If V/C ratios are greater than 1.20 and /or average delays are
consistent with LOS F conditions
2. Queue lengths — Options that score, "'acceptable" or ",marginal" in the first tier assessment
proceed to a second tier analysis of queue lengths. Queue Lengths are important because
they indicate whether adjacent intersections will disrupt each other's operations by virtue of
queuing from one affecting the other. This is a fairly simple analysis and could be taken
many.steps further to determine how signalization could maximize traffic flow through a
series of intersections, but queuing analysis is essentiallya fatal flaw's level analysis.
Queuing results report average queue lengths, the distance back from the intersection stop
bar (in feet) that queues Will reach during roughly half of the signal cycles, and 95 percentile
queues, the distance that will be exceeded by onlyfive percent of the signal cycles.
Intersections are: normally designed for the 95 percentile but average queue is a .
critical measure' because if describes conditions that occur on a. regular basis. Potential
results from this analysis are
a. Acceptable — 95th percentile queues do not reach ;adjacent intersections
b. Marginal`• — Average queue lengths do no reach adjacent intersections, but 95
percentile queues do:-
c. Unacceptable — Average queues reach adjacent intersection
FEH R. &I PFEP,S
TRANSPORTATION CONS'ULTAN'TS
Page 5
f p
Corona Road Interchange Evaluation
Transportation Technical Appendix
May
Corona Results
In conducting the Corona`Road interchange operations assessment, Fehr & Peers made'
assumptions about the geometric:.configuration of'iniersections. These assumptions are documented.
below.
• Corona Road would provide four through lanes (two in each direction).
• At signalized intersections, dual left -turn ,lanes�are provided wherever peak hour.leff -turn
volumes exceed 250 vehicles.
• At ramp intersections, free right -turn lane_ s (i:e.,, rightAurns that are not controlled by °the
signal and ,have dedicated 'turn lanes on the approach.with dedicated lanes on the departure
followed by merge) are assumed wherever, right -turn volumes exceed 500 vehicles: per
hour. -
Tier 1 results are shown'in °Table B -1: Appendix C contains the level of service printouts.
Table'B -1
Measure of Operations — Tier 1
Corona Interchange Alternatives
Alternative
Corona / "
Petaluma B � lvd
.North
Corona'/
McDowell
Northbound'
Interchange
Rams
Southbound
inteechange'r
Ramps
V/C
I
LOS
).
V%C
LOS
Dela
V/C
OS
'(
V/C
LOS
(Dela
AM Rbak Hour
1 - Rainier
0.72
C 26
0.80
D: .
0:64
(9
0.87
B 20
2 — Corona New Option
0.78
C 33
0.88
D 37
_A
0.77
C,(2 :
0.78,
C (22
3 — Coronna EIR'
0.78
C 33
0.88
D
0.95`
D 44
1,.04.
F 86
4 —'No Project '
0.88
D 43
0.89
D (41),
-
PM' Peak' Hour -
1 — Rainier - ._
0:72
C 32
0:74
C
064
A; 9'.
0.93,
17C 31
2— , Corona;New Option
0.90
D 52
0:88
D 48
0.79
C 20
0:88
G 30
3 — EIR
0.90
D 52
0:88
D 48
0.96
D'(48)
?,1.05'
F 164
4 - No Project'
0.56"
D 42
0.75
C 33 '
-
. _
_
_
Three alternatives survive, the Tier 1 operations assessment: Scenario 1 Scenario 2 and Scenario,
4. Scenario 3
scores a "marginal" Tier' 1. assessment rating, at the intersection of Corona.Road and
the Northbound 101 Ramps and an "unacceptable'' rating at °the intersection `of Corona Road and the
Southbound 101 Ramps. The "unacceptable" rating, at °the northbound interchange ramps is
primarily tied the lack of dual left -turn lanes1for' eastbound Corona Road traffic turning onto
Northbound US 101.
•
Tie , 2,analysis of the alternatives passing the Tier 1 analysis is shown in Table 8 =2. Scenario -4 is not
analyzed because there are no Highway 1 01 .ramp intersections under this alternative. , Based on the
Tier '2 analysis, Scenarios 1 and 2:have:acceptable operations when looking queuing conditions
between intersections.
FEHR & P.EE _s
TR'ANS'PORT.ATION CONSULTANTS Page
n
44
g :
Corona Road Interchange Evaluation
Transportation Technical Appendix
May 24, 2004
FLH R & PUFFS
TRAN'SPORTATIO'N CONSULTANTS
Page 7
Table B -2
Measure of Operations = Tier 2.
Corona Road Results
Alternative
Tier 1 Result
Distance between"
Maximum
Maximum 95
Intersections (ft)
Average
Percentile
Queue. Length
Queue
AM '.PM
AM PM
1 — Rainier
Acceptable
600
200 400
350 525
2 — Corona New
Configuration
Acceptable
800
(400) from,S6 Ramps to
Industrial Ave; 600 from.N6
225 (250)
350 (400)
Ramps to McDowell
Notes:
(1) The average and 95h
percentile are provided for the intersection
with the longest queue.
(2) For average,and 95 percentile queue lengths, AM values. are shown first and PM values are shown in parentheses.
3 Lengths are shown in feet
FLH R & PUFFS
TRAN'SPORTATIO'N CONSULTANTS
Page 7
Corona RoOInterchan Evaluation
Transportation Technical Appendix
May'24,2004
AOpendix- ' C
Level of Setvi'deaind Queue Length PrintbUts
F E' �, � R, PE R- S
TRANS PORTATION CONSULTANTS
Page 8