The URL can be used to link to this page

Home My WebLink AboutDowntown Traffic ModelDOWNTOWN TRAFFIC MODEL STUDY City Council Work Session May 17, 2016 ="La4 CITY OF IOWA CITY Presentation Outline What is the Downtown Traffic Model? Why the Study? Study Area Study Elements Model Output Study Results Staff Recommendations i r 111 CITY OF IOWA CITY What is the Downtown Traffic Model Study? Complex computer driven traffic model built to test transportation scenarios Produced by Shive-Hattery & Olsson Associates Led by a steering committee: Neighborhood & Development Services, Public Works, Engineering, Transportation & Resource Management, University of Iowa Multi -Modal: Bicycles, pedestrians, transit, private vehicles, and delivery vehicles Deliverables: Data collection - 39 intersections Recommendations based on Level -of -Service, traffic patterns, and overall operational impacts Why the Study? An attempt to satisfy a multitude of requests and expectations: University of Iowa interests Downtown streetscape project Capital Improvement Program projects Blue Zones designation Complete Streets Policy Bicycle Friendly Community status Public inquiry i r CITY OF IOWA CITY Study Area SHIVEHATTE-RY CAIILISRNA CMOFIO CITY '�1 Sas a' � 4 a 1 7 8 9 10 11 12 3 1 ' 1 13 14 15 16 17 l i Iry i i '''a i4 i i 18 119 2w0 21 22 23 d{ 1 11 -* i i 24 25 26 27 28 X29 30 31 32 33 i f I ♦ 4 i 1 i♦ at 1 34 35 36 37 38 39 Exi�;Truc iruTEr-;�;�cTmty (1) eC Al''O w .��,_ �18 1&,_ •P20 00 22 ,, 23 '..1 �6 27 a �r �31 � SHIVEHATTE-RY CAIILISRNA CMOFIO CITY '�1 Sas a' � 4 a 1 7 8 9 10 11 12 3 1 ' 1 13 14 15 16 17 l i Iry i i '''a i4 i i 18 119 2w0 21 22 23 d{ 1 11 -* i i 24 25 26 27 28 X29 30 31 32 33 i f I ♦ 4 i 1 i♦ at 1 34 35 36 37 38 39 Exi�;Truc iruTEr-;�;�cTmty Study Elements Market & Jefferson Streets: one -to -two way conversions Madison Street: 4 -to -3 lane conversion Clinton Street: 4 -to -3 lane conversion Gilbert Street: 4 -to -3 lane conversion Cleary walkway: Pedestrian actuated traffic signal Iowa Ave / Clinton Street & Iowa Ave / Madison Street: `All red' pedestrian phases Bicycle Accessibility — East to West • Priority signalizatio� �r • Iowa City Transit Interchange Relocation N CITY of IOWA CITY Study Results Model output shown in `seconds of delay' for traffic movements (translated into letter grades A -F for analysis) LOS LOS Score Pedestrian Bicycle A <2.00 <2.00 B > 2.00-2.75 > 2.00-2.75 C > 2.75-3.50 > 2.75-3.50 D > 3.50-4.25 > 3.50-4.25 E > 4.25-5.00 > 4.25-5.00 F > 5.00 > 5.00 Source: Highway Capacity Manual LOS DESCRIPTION Represents free flow. Individual users are virtually unaffected by the presence of others A in the traffic stream. Freedom to select desired speeds and to maneuver within the traffic stream is extremely high. Within the range of stable flow, but the presence of others in the traffic stream begins to B be noticeable. Freedom to select desired speeds is relatively unaffected, but there is a slight decline in the freedom to maneuver within the traffic stream from LOS A Within the range of stable flow, but LOS C marks the beginning of the range of flow in C which the operation of individual users becomes significantly affected by interactions with others in the traffic stream LOS D represents high-density, but stable flow. Speed and freedom to maneuver are D severely restricted, and the driver experiences a generally poor level of comfort and convenience. LOS E represents operating conditions at or near capacity levels. Freedom to maneuver E within the traffic stream is extremely difficult. Comfort and convenience levels are extremely poor and driver frustration is generally high. LOS F is used to define forced or a breakdown of traffic flow. This condition exists when F the amount of traffic approaching a point exceeds the amount that can traverse the point. LEGENN '✓ GdAWW pAWW 1 2 `.gAWB4 pA(A)IA' AA' If {' 7 B pc(q Iq A" 13 pe(a)A p6(B)Bl A B(B)m AC(B)B) r ,MIM ! B(B)BI 3 4 ®A(A)IBI wBB)BI A .:c 1c] IOl A C IBI IBI ! B:B)(B) ! BIBI dI 9 10 ®A(AIW bels :B1 E'. b' ASI e' !' I BBIBI 5 6 p A(A)W gel B (B)A A' A A(A)IN ! ' ! B(B)BI ifi{: CI Q.AWW pA IN IA) pA(B)IBI A• ABIBI BB A'halal IBI B' B All ! 1 BIBI IBI 14 15 16 17 gA(A)W 6 A(A)IN pS(B)(BI pA(A)W A• b' AB/BI IBI Aa(a)A ! I' r BIBI IBI ! A(A)IBI 18 19 20 21 ®A(A)W ®A(A)JN A' A' 24 25 �B(C) ICI6?A(AI IBI ®A(A)W G?E(F)IF1 A C(c):C1 A C(q IC) A C(CIICI A c(C)ld ! a(B)Icl I BBI IBI IF B(c)lcl ! 6(a)(cl 28 29 30 31 26 27 6 BBI ICI p0(C)1DI A c(q ICI Ac(c)Iq If BIBIBI ! B(B)ICI 32 33 AdSIIY LIIL05) Inti ,_ I " . LOS, (eel PM PEN( LOS (MIO DAY LOS) PM PILOS) A "PEI LOS (MIO DAY LOS' I EEAKLOSI "PEM LOS (,.. LOS)(PM PEM LOS1 •Xf.16'M10 ME CWLOGY GOES NOT EI TO UNSIOW17 INTERSECTIONS FOR BICYCLISTS ANO PECESTRIM'S ^W .N10 MEi QWLOOY DOES NOT EXTEND TO SIGNALMD INTERSECTIONS WITH eN ALLRED PEOESTN W( %MSE SHIVr--IATTCRY Q'\OLSSON iE*Q" :' IEXOSTONG ONTERSEO�OOP� LEVEL OF SIERVOCE • • • CIT101 IrIII t (39�' A(A)[Al A. pA(A)W A' GaA(A)W A. 4A(A)MI A• pA(A)W A• pA(A)IN A. 1(3 X381;: 34 35 36 37 38 39 AdSIIY LIIL05) Inti ,_ I " . LOS, (eel PM PEN( LOS (MIO DAY LOS) PM PILOS) A "PEI LOS (MIO DAY LOS' I EEAKLOSI "PEM LOS (,.. LOS)(PM PEM LOS1 •Xf.16'M10 ME CWLOGY GOES NOT EI TO UNSIOW17 INTERSECTIONS FOR BICYCLISTS ANO PECESTRIM'S ^W .N10 MEi QWLOOY DOES NOT EXTEND TO SIGNALMD INTERSECTIONS WITH eN ALLRED PEOESTN W( %MSE SHIVr--IATTCRY Q'\OLSSON iE*Q" :' IEXOSTONG ONTERSEO�OOP� LEVEL OF SIERVOCE • • • CIT101 IrIII Table 3: Existing Vehicular Intersection LOS and Delay (Seconds) Street Intersection LOS AM. Delay (sec) LOS Mid -Day Delay (sec) P.M. LOS Delay (sec) ldadison Street 0 0 0 Clinton Street B 18 B 12 B '12 Market Dubuque Street B 15 B 11 B 12 Street Linn Street 0 1 1 Gilbert Street B \ 13 B 11 12 Madison Street Clinton Street 10 g 10 10 B B 14 11 Jefferson Dubuque Street B 11 B 14 B 17 Street Linn Street 0 0 A 0 Gilbert Street B 13 B 14 6 16 kladison Street C 28 C 21 C 30 Clinton Street C 25 C 28 1 C 27 Iowa Avenue Dubuque Street 6 9 A '10 Linn Street 8 9 A '10 Gilbert Street '10 1'I B 11 Madison Street 9 9 A e. Capitol Street 3 4 A 4 Washington Clinton Street °1II 12 B 13 B 13 Street Dubuque Street 10 1 8 A 8 Linn Street B 12 B ................... 13 B 13 Gilbert Street B 11 12 1 B 14 College Linn Street 9 9 A 10 Street Gilbert Street 13 13 B 13 Madison Street 13 C 25 C 26 Burlington Street Capitol Street Clinton Street Dubuque Street 3 6 73 8 9 100 B 16 8 201 Linn Street B 15 Immm 18 C 32 Gilbert Street L. 26 1 C 26 D 38 Unsignalized intersections in Reci Market & Jefferson: two-way conversions • (._as: EXISTING - ��f►<< EXISTING SECTION A -A' EXISTING SECTION B -B' .a...B m�smB.a.mr.woan�aYeo rieummarlmo G19951RY&IYLMK fGiEm�Pu �� rim� srogE � Bl11FPolp MJUSE � SIQ'E A BBI9f ¢VaE1E5iR�r O ,uw�r-- �. i�a4.rcn,u�n O �---- ��£i � w2mma�vwsr I ti 1F- IIARI(EISiREE, � MmaumT'.' r�-iHfil I— P/PPA,q'dIBU9T£SBBUBDMG �, �' WRFIUN � � ,rrrEwiurouu �'E i • (._as: EXISTING - ��f►<< EXISTING SECTION A -A' EXISTING SECTION B -B' .a...B m�smB.a.mr.woan�aYeo PROPOSED SECTION A -A' CONVERSION • TRAFFIC SIGNAL MODIFICATIONS - $25k to $50k PROPOSED SECTION B -B' SHIVEI-IATTERY CAOLSSON. AZ& MARKET 87REET ONE-WAY TO TWO-WAY rieummarlmo fGiEm�Pu �� rim� srogE Bl11FPolp A ¢VaE1E5iR�r O ,uw�r-- �. i�a4.rcn,u�n O «PwiwnPwmr -_ , ,p3 PROPOSED SECTION A -A' CONVERSION • TRAFFIC SIGNAL MODIFICATIONS - $25k to $50k PROPOSED SECTION B -B' SHIVEI-IATTERY CAOLSSON. AZ& MARKET 87REET ONE-WAY TO TWO-WAY Market & Jefferson: two-way conversions vok t7 � v- --� TMS A J \ Nl� eIsm � �J L F r EXISTING it EXISTING SECTION A-A'LXISTING SECTION B -B' 'iler..lk,o:.�ue:e-ui. n.e.a o+btln; a vya.m hyo. PROPOSED SECTION A -A' CONVERSION • TRAFFIC SIGNAL MODIFICATIONS - $25k to $50k PROPOSED SECTION BA' SHIVEHATTC—RYtiII l JEFFERSON STREET ONE -'WAY 41 `�°,ar0=�°n°AY O'�OLSSON= crtra ¢m+cm Market & Jefferson: two-way conversions Pros Reduced speeds on Market Street and Jefferson Street Addition of bicycle lanes May balance vehicular volumes between Market Street and Jefferson Street Decreased vehicle delay on Dubuque Street Cons Transit and delivery vehicles may block through lane during stops Additional conflicts points for pedestrians, bicyclists, and vehicles Reduction in vehicular roadway capacity Additional direction of conflict for pedestrians at the Cleary Walkways Loss of on -street parking for new turn lanes $325,000 in costs to construct new pole / mast arms, signs, and pavement markings Additional cost for design & reconstruction of Jefferson / Clapp and Market / Rochester intersections Market & Jefferson: two-way conversions 1100 Jefferson Street at Cleary Walkway Crossing Iaao 3m em >oo E saa .ao tw1.e4 300 Sao 0 600M3 7.MW IM W.mW 1.00114 IIM" 12MMf Lwm IMM 3mm 4,WPM 600M1 600M1 Tk" Market & Jefferson: two-way conversions Summary Conversions should be limited between Clinton Street and eastern limits due to Cleary Walkway concerns The conversion between Madison and Clinton will not provide additional value to roadway users but would create additional conflict points for pedestrians A pedestrian actuated signal should not be introduced The conversion between Clinton and eastern limits will not result in a significant change in LOS for motorists The conversion of Market Street and Jefferson Street to two-way has a positive or neutral effect on the pedestrian and bicycle LOS The conversion is not shown to have a detrimental affect on north side streets 4 -to -3 lane conversion -'road diet' BEFORE Madison Street: 4 -to -3 Lane conversion W.__. seuuxs cfu,w d EXISTING EXISTING SECTION A -A EXISTING SECTION B -B' .y mr o mml+m CONVERSION PROPOSED SECTION A -A' PROPOSED SECTION BA' •arowx owa i au ie FIGURE 11 -mow OAOLSSON ; MADOSOM STREET FOUR -LAPSE TO THREE -LANE CONVERSION CONCEPT CIT) CM n i_k . • • _ _ _ CpYVU IC< �� CONVERSION PROPOSED SECTION A -A' PROPOSED SECTION BA' •arowx owa i au ie FIGURE 11 -mow OAOLSSON ; MADOSOM STREET FOUR -LAPSE TO THREE -LANE CONVERSION CONCEPT CIT) CM Madison Street: 4 -to -3 Lane conversion Pros Reduced speeds Additional mode of travel accommodated with bicycle lanes Center left turn lane may help reduce rear end collisions Fewer lanes for pedestrians to cross Roadway scale matches internal campus roadway character Low cost change Cons Transit will block through lane and bicycle lane during stops Slight increase in overall delay for vehicles and transit Potential for long southbound queues at Iowa Avenue during peak hours N. CITY of IOWA CITY Madison Street: 4 -to -3 Lane conversion Summary Only slight increases in overall vehicle delay The conversion of Madison Street has a positive or neutral effect on the pedestrian and bicycle LOS and will create a more friendly corridor The `all -red' pedestrian phase should be removed at the Iowa Avenue intersection if converted to a three -lane roadway A southbound right turn lane at Iowa Avenue should be considered to help decrease delay Potential for bike lanes to be added to Iowa Avenue between Madison Street and Riverside Drive N. N CITY of IOWA CITY Iii r d , Alm r�- I t NWR IVEINIE 3w 4' atip _ ...s mWow. a.41 � x JY►t7 �. J , EXISTING CONVERSION FIGURE 15 SHIV:HAITCRY ,.' OLSSON ! '3 D 'E E0 i0DGiE FOR CKE RUGS LffY C7UMEF98M.M CC)N0 E PT Clinton Street: 4 -to -3 Lane conversion r p u r IY f .;NNFR$RYGry1[{w.ZT f a. II\ J �r (•i r � I �ul��+ �lIri' mf* EXISTING EXISTING SECTION A -A' EXISTING SECTION B -B' j,4 f i . �. uvrvms wra oLRAra ,� ry� A 1, � I � LEY F✓ L � ✓� K� c 1 L AW n „ PROPOSED SECTION A -A' SHIVEHATTERY '- OLSSON" i CONVERSION PROPOSED SECTION B -B' • TRAFFIC SIGNAL MODIFICATIONS - $25k to $50k it ror u., d.m,w i FIGURE 9 W T TF_EET F' ,A oF.-d E7 TH EE—d .: E EF: 0 7EF'4 Clinton Street: 4 -to -3 Lane conversion Pros Reduced Speeds Additional mode of travel accommodated with bicycle lanes Center left turn lane may help reduce rear -end collisions Fewer lanes for pedestrians to cross Roadway scale matches downtown urban setting Improvement in LOS for pedestrians Low cost change Cons Transit may block through lane during stops Bicycle lane located at the back of angled parking stalls Trucks may block bicycle lane / thru lane during deliveries Reduction in vehicular roadway capacity and minor increase in delay for vehicles Burlington Street intersection suffers the most increase in delay r CITY OF IOWA CITY Clinton Street: 4 -to -3 Lane conversion Summary The conversion will increase bus travel times by up to two minutes of additional delay — primarily for northbound routes The conversion has a positive or neutral effect on the pedestrian and bicycle LOS Overall slight increases in delay and traffic queues expected In general, the traffic impacts of the lane reduction are greater during the mid-day when more University classes are occurring The `all -red' pedestrian phase should be removed at the Iowa Avenue intersection if converted to a three -lane roadway it CITY OF IOWA CITY Gilbert Street: 4 -to -3 Lane conversion 3 .. "p'NA CIIYAPFA 4a _ �STA.. LLQ � ST PAIA8 GRJCEITY AUYAIAIBLOY.INIY C'+� �ry "�- RE(AFAiNM'LBlIFR � 3� finAMu ( �q � -�l ■� �` L� = KAY EXISTING EXISTING SECTION A -A' YNne! M nwwiNfn M amd >&L9 w PRw� M f . • •T 3IFEEI • O ' � _` =A,— LF, � • I. • • I.^M'AG1Y c lNf� arrxui 1. .: Glee ISARfEr n I NISTCFKK b� y ST PAUIB LAN cNePa XA4NS \ .M� GRGCERY y' (� SAA IW_ll 6 PROPOSED SECTION AA* SHIVE'-IATTERY O\OLSSON�. • .-A.., g CONVERSION • TRAFFIC SIGNAL MODIFICATIONS - <$25k • TRAFFIC SIGNAL MODIFICATIONS - $25k to $50k Ga LBEJRT STREET FOUR -LANE 4O THREE -IANC Gilbert Street: 4 -to -3 Lane conversion Pros Reduced speeds Additional mode of travel accommodated with bicycle lanes Center left turn lane may help reduce rear -end collisions Fewer lanes for pedestrians to cross Cons Transit may block through lane during stops Reduction in vehicular roadway capacity Significant southbound queuing may cause `gridlock' at the College Street intersection Potential issues with emergency response Gilbert Street: 4 -to -3 Lane conversion Summary The conversion of Gilbert Street to a three -lane has a positive or neutral effect on the bicycle LOS The conversion increases the level of delay for vehicles in all periods for the Burlington Street and Gilbert Street intersection Additional studies on the Burlington/Gilbert intersection geometry and signal timing should be performed The consultant indicates that "This conversion is not recommended unless a solution to Gilbert Street and Burlington Street intersection can be found such as adaptive signal technology or if the trade-off for additional vehicle delay is considered acceptable" Staff Recommendations Move forward with Clinton & Madison Street 4 -to -3 lane conversions with bike lanes; integrate with on-going Clinton/Burlington & Madison/Burlington designs (2017 & 2018) Consider Gilbert Street 4 -to -3 lane conversion with bike lanes after successful implementation of Clinton & Madison Street conversions Initiate design and public outreach for Market & Jefferson Street one -to -two way conversions in 2018 �r CITY of IOWA CITY