Study Methods and Assumptions

Size: px

Start display at page:

Download "Study Methods and Assumptions"

Dwain Gregory
5 years ago
Views:

2 Study Methods and Assumptions Analysis conditions and study area Demand forecasts and projects Performance measures LOS standards DRAFT ANALYSIS FOR',EEVI.

3 o I Conditions and Study Years Conditions Year I: Existing 1 NoB.µild 1 I Constrµc_t i9rtl If I Ultimate -. ' x 22 x x 235 x x Existing & No-Build Conditions Ultimate Condition - Assumes both 1-9 Two-Way Transit and HOV and East Link projects are built and operating - Option 1: Ml vehicles able to use HOV lanes and ICW - Option 2: Ml vehicles restricted from HOV lanes and ICW, DRAFT AN!\LYSIS FOR RE'i

Conditions and Study Years East Link Construction - Mid-point of construction (22) - 1-9 Two-Way Transit and HOV Project completed - Operational

4 Conditions and Study Years East Link Construction - Mid-point of construction (22) Two-Way Transit and HOV Project completed - Operational Scenarios: Ml SOV eligible to use the HOV lanes and ICW Ml SOV restricted from the HOV lanes and ICW HOV lane converted to a general-purpose lane

$o Study Area \./ I :.. r C...,11 \ \ 1 J'. \ \... -.9... 1 :s.._.$

5 o Study Area \./ I :.. r C...,11 \ \ 1 J'. \ \ :s.._ from 1-5 to 1-45 Analysis conducted for both AM and PM peaks Study area includes freeway and lo.cat S;tu.eets DRAFT ANALYSIS iffor REVI

$Q 11 '\ '- '2d... se '" SI! 7ai.iA" SE -... il... z :: :> < w Cl) t& - Cl.l / r>... I l ASC 1 l:s 71::1-$( l't 7lr\J... tt... Ii r i' l :1"' -.$

6 Q 11 '\ '- '2d... se '" SI! 7ai.iA" SE -... il... z :: :> < w Cl) t& - Cl.l / r>... I l ASC 1 l:s 71::1-$( l't 7lr\J... tt... Ii r i' l :1"' -..u Clt11V11:1 1 il.. fi : l:""r iii,: JS:.. r!j>1f'".."" a..., Ml""ll llq;\a U... '1!llllh.S[ c. I I - ti) 78th.s::.,... N llj l.ll I 11th

o o o Future Forecasts and Projects PSRC model - Forecasts for 22 and 235 - Utilize PSRC adopted Land Use Targets forecast Sound Transit model - Bus and light rail ridership forecasts Reasonably

7 o o o Future Forecasts and Projects PSRC model - Forecasts for 22 and Utilize PSRC adopted Land Use Targets forecast Sound Transit model - Bus and light rail ridership forecasts Reasonably foreseeable projects: - Includes Connecting Washington projects Two-Way Transit is completed immediately prior to East Link construction - ST 2 program is complete by ST 3 is not assumed DRAFJi ANALYSIS F.OR RE

Performance Measures and Standards Performance Measures - Vehicle and transit demand forecasts - Intersection LOS and vehicle queues - Vehicle travel times

8 Performance Measures and Standards Performance Measures - Vehicle and transit demand forecasts - Intersection LOS and vehicle queues - Vehicle travel times Agency LOS Standards -WSDOT LOSE - Mercer Island (town center) LOS C - Mercer Island (outside town center) LOS D VISSIM and Synchro used for analysis results

9 o Draft Analysis Results Existing Conditions/Field Verification Future Traffic Forecasts and Travel Patterns Intersection LOS Travel Times on Mercer Island 1-9 Ramp Operations

Existing Conditions Intersection LOS 2161Exlstfn1,tandltlons lhtersection 1 - ID lnter5ectton - I 1stanifan1 1 21 W Mercer Way/1-9 Ramp E 22 W Mercer Way/SE 24th Street D A B 23 76th Avenue SE/N

10 Existing Conditions Intersection LOS 2161Exlstfn1,tandltlons lhtersection 1 - ID lnter5ectton - I 1stanifan W Mercer Way/1-9 Ramp E 22 W Mercer Way/SE 24th Street D A B 23 76th Avenue SE/N Mercer Way/1-9 Westbound on-ramp E A c 24 76th Avenue SE/SE 24th Street c A B 25 77th Avenue SE/N Mercer Way c E 26 77th Avenue SE/1-9 Westbound express lanes ramp E A B 27 77th Avenue SE/1-9 Eastbound Off-Ramp E B B 28 77th Avenue SE/Sunset Highway SE c B c 29 77th Avenue SE/SE 27th Street c B B 21 8th Avenue SE/N Mercer Way c c c 211 8th Avenue SE/1-9 WB/EB HOV Direct access E A B 213 8th Avenue SE/SE 27th Street c B c st Avenue SE/North Mercer Way D c B 215 Island Crest Way/N Mercer Way/1-9 Westbound off-ramp E B c 216 Island Crest Way/1-9 Eastbound On-Ramp E c c 217 8th Avenue/SE 28th Street c A Island Crest Way/SE 28th Street c c c 22 Island Crest Way/SE 4th Street D c D th Avenue/SE 4th Street D A c 222 East Mercer Way/1-9 Westbound ramp E B c Notes: 223 East Mercer Way/1-9 Eastbound off- ramp E 8 A 224 East Mercer Way/1-9 Eastbound on-ramp/se LOS Standards by agency are: Mercer Island - LOS D (LOS "C"for Town Center Arterial Intersections), WSDOT- LOSE l LOS DRAFJ" ANLYSIS frg F.l F.tE\llEW

$Existing Conditions Travel Times lldl s..19 - ) ROAOK; ' I"- \ t I Route 38 T 76th Avenue.,... SE (via N Mercer Way) l l..a... I II,: Iii ft... IC r : Route 1 W Mercer way x II MERCEJ ;,\VIII ICJWn l.$

11 Existing Conditions Travel Times lldl s ) ROAOK; ' I"- \ t I Route 38 T 76th Avenue.,... SE (via N Mercer Way) l l..a... I II,: Iii ft... IC r : Route 1 W Mercer way x II MERCEJ ;,\VIII ICJWn l..t!nlll!f'i I ISi.AND 1'41.1 Jtzn11111., l -,,.....? 1.;;,.:; al,.,,. - l ;:I J II ); r " r 1.,.! '1!Ci ' o I Travel Time Route I 1 - W Mercer Way I 2 - Island Crest Way (Outer Roadway) 'l - 3A- 76'h Avenue SE : -- (via Town Center) :::""'...i r/ /J('.,,,..!- It i f f th Avenue SE ti h i trl. i U.TI:>S. ""-.- I ii t... ' (via N Mercer Way) ".. r ' AM Peak Travel lime (minutes) I

12 Travel Pattern Field Verification Conducted origin-destination counts on N. Mercer Way in AM - Up to 6 vehicles/hour use Island Crest Way WB offramp to 77th WB center roadway on-ramp Average vehicle occupancy (AVO) count on 1-9 and Island Crest Way ramp - 16 /o HOV share in the WB direction in AM Ramp utilization in PM period DAFT ANAl.L YSIS ifh IREV..1.

, o o o 1-9 and Mercer Island Traffic F'orecasts 1-9 across Lake Washington.Existing 21.6.

13 , o o o 1-9 and Mercer Island Traffic F'orecasts 1-9 across Lake Washington.Existing Future 235 Percent Growth AM Peak Hour 11,8 vehicles 12,9 vehicles 9% PM Peak Hour 13, 1 vehicles 14,4 vehicles 1% Mercer. 1 1sland L - _J ' Existing 216 _JL_ Fu re 235 _!l Percent - Total Volume HOV /o Total Volume HOV ; I Growth AM To Mercer Island 2,5 13% 2,75 13% 1% Peak ; Hour From Mercer Island 3,3 14% - 3,7 i 14% 12% PM To Mercer Island 3,4 17% 3,85 17% 13% Peak Hour From Mercer Island 3,25 19% 3,55 I 19% 9% Source: PSRC model DRAF.T ANALYSIS FOR REVI

$Mercer Island AM WB 235 Travel Patterns - - ----- -- -- "-. Nat to Sc=* 761hASE on-«amp Island crest w., :ic? l '\. \ 1.,.. N Sf2".,. Bulld1 -Bulld2 11 :+ :ll t'i t W Mercer Way 51. on-ramp r.$

14 Mercer Island AM WB 235 Travel Patterns "-. Nat to Sc=* 761hASE on-«amp Island crest w., :ic? l '\. \ 1.,.. N Sf2".,. Bulld1 -Bulld2 11 :+ :ll t'i t W Mercer Way 51. on-ramp r.mt:j 43 I tltn IL 1-;t;U;, llf'$t \ \ t' /;(. :ii... '(" t :;: Ill l \ 'Ii ' ; J! H/U.,...p.. m.., Sf.lmll SUlnlSI 1! "', <... 1i ::<..,. II: 'i!1 ' Build Opt 1 Westbound On-Ramp Volume Build Opt 2 Westbound On-Ramp Volume : jl Build Opt 2 Volume Is Greater than Build Opt 1 Build opt 2 Volume Is Less than Build Opt 1 Build Opt 2 Volume Is Equal to Build Opt 1 I.. j, SI!)'. < fi.. t..... OK :icj...! SE J1rclt 14thU :( It I '1' ->- :t 1! 1' " I; l:t.. i ii t I.. i! l:t. t lej)r.\ * \!l jsij15ti tt.uth Pl.,.c \!l. ):: Sf )i!mi = :IC :>! ::< l J t :le! SEl91115t.r: fi -Ef:leJ! ie l:,.;s! " j SE 41 St ' a; i i SE.6\h St hr.tdl,,_,., fl!...,. ' fl '"' " :'( l f; \ l I: l I - st 1t1is1 "' I " -e " \ )I\ ll t u o;... E Mercer Wlfl Oft.Ramp 235 City<f -... :IJ Sf<4lllSt.,.., i '.. 'If. ' \I... \ \ 4-/< ::.a 'j:. i... J DRAIT ANAILYiSIS.FOR ievie

Mercer Island PM EB 235 Travel Patterns Nol!to5'* - Bulld WWayu Off-Ramp 235 - i Roanoke / "lil'xt!isi - isttisi 2so r Jef"k +is.. I f, ;J. J,'"iil:i 'fl. II: 1- 'll 'llmil st:jlnlsi, "' 5.

15 Mercer Island PM EB 235 Travel Patterns Nol!to5'* - Bulld WWayu Off-Ramp i Roanoke / "lil'xt!isi - isttisi 2so r Jef"k +is.. I f, ;J. J,'"iil:i 'fl. II: 1- 'll 'llmil st:jlnlsi, "' 5. llc ' )l-1.&ch SI :X "' l! 17th Ave SE Off-Ramp J 47.. RllSTi.tl.. :le 11: [ +HI " l! Bulld Opt 1 westbound on-ramp Vobne hiidil Buld Opt 2 Westbound Oft-Ramp Vobne Opt 2VolumeIsGreaterthanBulldOpt1 BuUd Opt-2 Volume Is Less than Bulld Opt 1 Bulld Opt 2 Volume is Equal to Build Opt 1 DRAFT ANALYSIS FOF.:UREVI - llllo Island crest Way Off-Ramp (HOV) ---""" I r <Mlwr IC: I 63 Island Oest Way M -.. Off- Ramp fout :) a: <;:: -1( )4!tft * t lfj",; - \. R:!Siti s1i:.sr l4t1t Pl it'.. t 1 i'- "' -i<. St'J6111SI,,.."' I I,_ <J.'Y' bl tj(!lc l J! < :ic... : SE4'>UIS! < l! J; snort. s1 - :. l I!lC SlHlhS. i,... Sl.4kl,St... l \ E Mera!rWay Off-Ramp S. HlhSI,,.._ :II t ,. 1, r ' N " i' 1 35 I',..._ lllw-< I I 135 ' - \ Ir : "\'I' '\... "' t \. \ 4-,AOC IJ I II \ J.':.. J

Initial Future 235 AM Results 76"' Avenue SEIN Mercer Way/ 1.9J B "li:lla r 1' L Bulld"Optlon 2 JL Build Optlolli2 - - - Westbound On-ramp ur - - P ion J!

16 Initial Future 235 AM Results 76"' Avenue SEIN Mercer Way/ 1.9J B "li:lla r 1' L Bulld"Optlon 2 JL Build Optlolli Westbound On-ramp ur - - P ion J! (unmitigated) (mitigated), Intersection LOS LOSB LOSE AM Peak Westbound approach LOS LOSC LOS F Hour Westbound Queue Length feet >1/2 mile Travel Time2 4 mins >1 mins -- Notes: 1 - Queue storage length is 75 feet to adjacent intersection at 771h Ave SEIN Mercer Way 2 - Travel time route begins at Island Crest Way/SE 28th Street and ends at W Mercer Way on-ramp gore - - LOSS LOSB 425 feet 4 mins Notto Scale t iv f SE74UI "t i XI ;f!l > > ;; ' 5 > <SI. 4- g f lr I.. i f 7 > c 1:1 SE 2-CUISI Luther Butbank P:ltlc I Mercet lshlt!d Ct>mmiiiiity & E BEAUMONT Route - Via N Mercer Way From: Island Crest Wav/SE 28th Street To: Westbound 1-9 via 76th Avenue SE On ramp DRAFT ANALYSIS fror F.lEV:IE

o o o 76 1 h WB On-Ramp Modification Modified 76th WB on-ramp and ramp terminal to: - Based on 235 analysis, modify transit-only bypass to a metered shoulder when

17 o o o 76 1 h WB On-Ramp Modification Modified 76th WB on-ramp and ramp terminal to: - Based on 235 analysis, modify transit-only bypass to a metered shoulder when storage is needed (similar to Island Crest Way eastbound on-ramp). - Adjusted ramp metering rate to accommodate onramp demand - Signalize 76th/North Mercer Way ramp terminal

18 Year 235 Intersection LOS 235 Future Conditions AMPHkttour PM Peek ttour Intersection I LOS ID lnlersectjon standanf" :1 BulJd 2 21 lw Mercer Way/1-9 Ramp I E I B I 8 I B I C 22 W Mercer Way/ SE 24th Street D A B B B, th Avenue SE/ N Mercer Way/1-9 Westbound on-ramp E B B C C ' I 24 76th Avenue SE/ SE 24th Street C 8 B B 8 25 nth Avenue SE/ N Mercer Way c B B A A I 26 lnth Avenue SE/HID Westbound express lanes ramp I E 27 lnth Avenue SE/1 9 Eastbound Off Ramp I E 28 I 77th Avenue SE/ Sunset Highway SE I C 29 I nth Avenue SE/ SE 27th Street I C 21 l8th Avenue SE/ N Mercer Way I C 211 l8th Avenue SE/ 1-9 WB/ EB t!ov Dlrea access I E 212 l8th Avenue SE/1-9 EB HOV Oirea access I E 213 l8th Avenue SE/ SE 27th Street I C st Avenue SE/ North Mercer Way 215 Island Crest Way/ N Mercer Way/ 1 9 Westbound off-ramp E 216 II Island Crest Way/1 9 Eastbound On-Ramp I E 217 IBOth Avenue/ SE 28th Street I C 218 I ls land Crest Way/ SE 28th Street I C 219 I Island Crest Way/ SE 3th Street I C 22 I Island Crest Way/ SE 4th Street I D 221 l78th Avenue/ SE 4th Street I D 222 I East Mercer Way/1-9 Westbound ramp I E 223 I East Mercer Way/1-9 Eastbound off-ramp t E 224! East Mercer Wav/1-9 Eastbond on-ramp/ SE 36th Street I E Notes: 1 LOS Standards by agency are: Mercer Island - LOS D (LOS "C" for Town Center Arterial Intersections ), WSDOT LOS E LOS resutts include all East Li nk Final EIS mit igation and 76th Avenue ramp modifications. B B B c B A c c c c B c N/A c A 8 B 6 B I B I B B ll C I C 6 I B I B c,, c l c B I 8 I B A I A I A c I c c I I c c c c I c I c B I B I B c I c I c N/A I N/A I N/A C I D I D A I B I B 8 c c : I : I : I DRAFT ANALYSIS lr'or REV IE

$Year 235 AM Travel Times --- r r r i: JI - '*- Rout l W Mam Way 111;. - N[llC(. :K\IM IOWTU.ftllet'J I ISl,ANO, I I,, IWtr f ;..O::'l"" 'I. r -t-' ',, 1\ s Ir 1 f ' "....... ft,,. ' a: f..;.. ; t.$

19 Year 235 AM Travel Times --- r r r i: JI - '*- Rout l W Mam Way 111;. - N[llC(. :K\IM IOWTU.ftllet'J I ISl,ANO, I I,, IWtr f ;..O::'l"" 'I. r -t-' ',, 1\ s Ir 1 f ' " ft,,. ' a: f..;.. ; t. i" ; i'.. :--.. J.... I I I: ; I- '- z ll ".:. 'C I ""II ' ""'" 1 I '. Travel Time II AM Peak Travel llme (mlns) Route Ill Build Opt 1 Build Opt W Mercer Way Island Crest Way 4 3 3a h Avenue SE (via Town Center) 3b - 761h Avenue SE (via N Mercer Way) Average Travel Time {weighted by traffic volume) DRAFr ANALYSIS FOR!REV

Potential Intersection Mitigation West Mercer Way & 24th Mercer Island Final EIS Southbound left-turn Avenue SE 8th Avenue SE & SE 27th Mercer Island Final EIS Install traffic signal Street 77th

20 Potential Intersection Mitigation West Mercer Way & 24th Mercer Island Final EIS Southbound left-turn Avenue SE 8th Avenue SE & SE 27th Mercer Island Final EIS Install traffic signal Street 77th Avenue SE & North Mercer Island Final EIS Install traffic signal Mercer Way 77th Avenue SE & 1-9 WSDOT Final EIS Install traffic signal eastbound off-ramp North Mercer Way & 76th WSDOT Final EIS/ Final EIS - Modify westbound westbound on-ramp Updated Analysis channelization Updated analysis - install traffic signal and modify ramp 76th westbound on-ramp WSDOT Updated Analysis Re-stripe transit only bypass to metered shoulder when needed

,, ~ :!! ~ ... a.. ~ C\I. c (1) ca.a. c, CJ. C') c.o. (1) Cl) Cl)

$,, ~ :!! ~ ... a.. ~ C\I. c (1) ca.a. c, CJ. C') c.o. (1) Cl) Cl)$ a..... C') c.o c,... - C\I "',, c (1) ca.a :!!... CJ (1) Cl) c Cl) :E O> -I Study Methods and Assumptions Refresher Conditions and years Study area Future forecasts and projects Performance measures DRAFT.ANALYSIS