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Home My WebLink AboutItem 7.1 DB&HansenTrffcStdyRsltCITY CLERK AGENDA STATEMENT CITY COUNCIL MEETING DATE: May 20, 1997 SUBJECT: Traffic Study Results - Dublin Boulevard/Hansen Drive Intersect:.m Report Prepared by: Lee S. Thompson, Public Works Director EXHIBITS ATTACHED: 1) 3) Traffic Signal Warrants / Stud), Results Resolution for No Parking Zone Location Map RECOMMENDATION: 1) 2) Direct Staff to develop a Capital Improvement Project to construct a traffic signal at this intersection for review of funding in the upcoming 5-Year Capital Improvement Program. The signal project could be constructed either ahead of or with the "Dublin Boulevard Improvements - Silvergate to Hansen" project. Adopt Resolution establishing No ParNng Zone on Dublin Boulevard east of Hansen Drive. FINANCIAL STATEMENT: The estimated cost to construct thc traffic signal, plus relC:ed improvements of the roadway approach, would be approximately. $340,000. DESCRIPTION: At the March 4, 1997, City Council meeting, the City Council received a request from the Briarhill Homeowners ,Association that a traffic signal be installed at the intersection of Dublin Boulevard and Hansen Drive. The City Council directed Staff to proceed with a traffic signal warrant stud),. The signal warrant study has been completed, and this intersection does currently meet three of the warrants for installation of a signal. Staff has also reviewed the intersection to determine whether interim improvements would help the existing situation, with the following results: g:\agenrnisc\dubhans2 COPIES TO: Briarhill Homeowners Assoc. Oleg Dubney Bay Tree Tenants ITEM NO. 7.1 The sight distance from Hansen Drive to the west could be improved by removal of some of the plant material on the north side of Dublin Boulevard just west of the intersection. This will be cut back by the City's Maintenance Staff for better sight distance up the hill. Two additional right turn arrows will be installed in the westbound Dublin Boulevard right turn trap lane to better warn motorists approaching Hansen Drive. Installation of 210 feet of No Parking Zone on the north side of Dublin Boulevard, east of Hansen Drive w'ould improve visibility. Allowing for space that is already taken by driveways, this would eliminate approximately five parking spaces in front of 11700 Dublin Boulevard (Dubney building) and approximately four spaces in front of the Bay Tree office complex at 11740-11750 Dublin Boulevard. This area will eventually be a dedicated right-mm lane once the second westbound lane is extended to Silvergate Drive. Staff recommends that the City Council direct Staff to proceed with the preparation of the traffic signal project' as a Capital Improvement project for review in the upcoming 5-Year Capital Improvement Program. Staff further recommends that the City Council adopt the resolution establishing a 21 O-foot No Parking Zone on the north side of Dublin Boulevard east of Hansen Drive. Page 2 Trartsport3tion Consultants MEMO May ] 3, 1997 Project No.: 157-001 Task 59 To; From: Subject: Mr. Mehran Sepehri Christopher S. Kinzel ~ Dublin Boulevard/I-Iansen Drive Sisal Warrant Analysis T.IKM has evaluated the need for U'affic signal control at the inters~fion of Dublin Boulevard and Hansen Drive under e.,dsting conditions. Attached are the warrant evaluations band on Caltrans' Traffc Manual. Table I pre~nts a summar3.' of those warrants. Table I: Traffic Signal Warrants - Dublin Boulevard/Han~en Drive Number Name Met? 1 Minimum Vehicular Volume No 2 Interruption of Continuous Traffic No 3 Minimum Pedestrian Volume No 4 School Crossings No 5 Pro~essive Movement No 6 Accident Experience No 7 Systems Warrant Yes 8 Combination of Wan-mats No 9 Four-Hour Volume Warrant Yes 10 peak Hour Delsy No l I Peak Horn Volumes Yes As the table indicates, three of the warrants are currently met. During the a.m. peak hour, minor movements at the intersection currently operate at unacceptable levels of service. Therefore, TJKM recommends that the intersectio~ be siD~alized- Ultimately, the section of Dublin Boulevard between Hanseu Drive and Silvergate Drive w/It be widmed to four lanes. However, the ir~terim condition v-ill remain two lanes. There are some consequences of the interim signalization that will ,ced to be addressed in conjunction with the signal installation: 4234 Hacienda Drive, Suite 101, Pleasan'. M.r. Mehraa Sepehr/ Page 2 April 16, 1997 Reconfiguration of the ~'o ~dr/veways on the south side of the intersection to provide single access point. Location of signal heads to maximize visibiliw. (For example, a near-side pole for eastbound traffic could be problematic.) · Provision of adequate storage Isn~h for eastbound-to-northbound left tums. · "Snappy" timing (or queue detection) to ensure that eastbound a.m. (a~d Sunday) through traffic does not back up to Silvergate Drive. TJKM has also investigated sight d/stance at the intersection. Due to sight distance obstructions on both sides of the intersection, it is recommended that, at least until the intersection is sigrmlized, the following improvements be implemented: (1) Trimming of bushes along the north side of Dublin Boulevard west of the intersect/on to provide 440 feet of sight d/stance between vehicles pulled forward on the southbound approach and vehicles traveling east. (2) Painting of reft rnrb alnng the. nnr~h side. nf Dublin Bnnlevard east of th: inter,s=c~ion approximately 210 feet, to the second driveway east of Hansen Drive) to provide a40 feet of sight d/stance between vehicles pulled fom'a.rd on the southbound a[rproach and vehicles traveling west. 4234 Hacienda Drive, Suite 10l, Pleasanton, California 94585-2721 9-6 TRAFFIC SIGNALS AND LIGHTING III m~ll I Figure 9-1 TRAFFIC SIGNAL WARRANTS Traffic Manual DIST CO RTE PM CALC DATE CHK DATE Critical sp~ed of major street traffic >_ 40 mph ...... In bui~, up area of isolated community of .c 10.000 pop .......... WARRANT 1 - Minimum Vehicular Volume Critical Approach Speed Critical Approach Speed or 10{7'4, SATISFIED 80% SATISFIED RURAL (R) URBAN (U) YES [] NO ~ YES [] No ~ -lout MINIMUM REQUIREMENTS (80% SHO,~WWN IN BRACKETS) .. '-u I(R'~(,~ u 1R bO/~ ~,,, , ., ; APPROACH 2 or ~o~ ~, '~ ~NES Higher ~pr~. 150 105 ~0 140 ~ mph mph WARRANT 2 - Interruption of Continuous Traffic MINIMUM REQUIREME~S (8~% SHOWN IN BRACKE~) APPROACH ~ 2 or more ~ ~pr~s. ~)or S~t (~) I H~h~t~pr~. 75 ~ ~ ~nor s~t (~)~ (~) loo% SATISFIED YES [] NO ,~ ~ATISFIED YES ~ NO [] WARRANT 3 - Minimum Pedestrian Volume 10~/o SATISFIED YES [] NO ~ REQUIREMENT FULFILLED Pedestrian volume crossing the major street is 100 or more for each of any four hours or is 190 or more during any one Yes [] No [~ hour; AND There are less than 60 gaps per hour in the major street traf- fic stream of adequate length for pedestflans to cross; AND Yes ~ No [] The nearest traffic ~ignal along the major street is greater ' Yes .J~ No [] than 300 feet; AND ,. The new traffic signal wi;l not seriously disrupt progressive Yes [] No [] traffic flow on the major street, .,, The satisfaction of a warrant Is not necessarily Justification for a signal. Delay, congestion, confusion or other evidence of the need for right-of-way assignment must be shown. Traffic Manual I II TRAFFIC: SIGNALS AND LIGHTING I I IIII I When the 85th percentile speed of major street ual'ftc exceeds 40 miles per hour, or when thc intersection lies within a built-up area of an isolated community having a population of less than 10,000, the peak hour volume warrant is satisfied when the plotted point, referred to above, falls above the curve in l~gure 9-9 for the existing combination of approach lanes. 9-01,3 Guidelines for Left-Turn Phases Since sepa.,-ate signal phases for protected left tums will reduce the green time available for other phases, alternate means of handling left turn conflicts should be considered first. The most likely possibilities are: 1. · Prohibition of left turns. This can be done · only if there are convenient alternate means of making the movement. Typical alternate means are: A series of fight and/or left turns around a block to permit getting to the desired destination; or Making the left turn at an adjacent unsignalized intersection during gaps in the opposing through traffic. Geometric changes to eliminate the left turn. An effective change would be a complete separation or a complete or partial "clover leaf' at grade. Any of these, while eliminating left turns, requires additional cost and right of way. Provide protected-permissive or pennis-. sivc-protected left turn operation. Thc protected left turn interval may be prohibited during certain periods of ~he day to allow only permissive intervals :for left turn movement in order to increase the green time available for other phases. Refer to Section 9-03.g for the requirements of protected-permissive or permi~iyc-l~rO£ectcd left mrn nI~eration. Protected left turn phases should be considered where such alternatives cannot be utilized, and one or more of the following conditions exist: Accidents. Five or more left turr accidents for a particular ]cfr turn movement during a recent 12-month period. Delay. Left-turn delay of one or more vehicles which were w~ifing at the beginning of the green interval and are still remaining in the left turn lane after at least 80% of the total number of cycles for one hour. Volume. At new intersections where only estimated volumes are available, the fol- lowing criteria may be used. For a pre- timed signal or a background-cycle- controlled actuated signal, a left mm vol- ume of more than two vehicles per ap- proach per cycle for a peak hour;, or traffic-actuated signal, 50 or more ".:(.':-i mining vehicles per hour/n one direction with the product of the turning and con- flicting through traffic during the peak hour of 100,000 or more. o Miscellaneous. Other factors that might be considered, include but are not limited to: impaired sight distance due to horizontal or vertical curvature, or where there is a large percentage of buses and trucks. 9-01.4 Removal of Existing $lgnals Changes in traffic patterns may result in a situation where a traffic signal is no longer justified. When this occurs, consideration should be given to removing the traffic signal and replacing it with appropriate alternative traffic control devices. Traffic Manual TRAFFIC SIGNALS AND LIGHTtNG 9-7 1-1gg2 Figure 9-2 TRAFFIC SIGNAL WARRANTS WARRANT 4 - School Crossings WARRANT 5 - Progressive Movement ....--...--------- MINIMUM PEOUIREME~T?~- DISTANCE TO NEAREST SIGNAL ON ONE WAY ISOLATED STREETS OR STREETS WITH ONE WAY TRAFFIC SIGNIFICANCE AND ADJACENT SIGNALS ARE ,50 FAR APART THAT NECESSARY PLATOONING & ,,SPEED CONTROL WOULD BE LOST _ _ Not Applicable [] See School Crossings Warrant Shoat [] SATISFIED YES [] NO [] FULFILLED ON 2-WAY STREETS WHERE ADJACENT SIGNALS DO NOT PROVIDE NECESSARY PLATOONING AND SPEED CONTROL PROPOSED SIGNALS COULD CONSTITUTE A PROGRESSIVE SIGNAL SYSTEM YES"~ NO [] WARRANT 6 - Accident Experience SATISFIED _ WARRANT ~ WARRANT 1 - MINIMUM VEHICULAR VOLUME SATISFIED F ~,R, ....... ,~rtr~l [eTlON OF CONTINUOUS TRAFFIC SIGNAL WILL NOT SERIOUSLY DISRUUPT pROGRESSIVE TRAFFIC FLOW ADEQuA I t- I H1AL OF LESS RESTRICTIVE REMEDIE~ HAS FAILED TO REDUCE A~RtDFNT FREQUENCY ACC. WITHIN A 1~ ~N I m ~,~ ~ 7~ ................. -- MINIMUM R~DUIREM~ NUMBER OF ACCIDENTS YES [] NO N NoE3 WARRANT 7 - Systems Warrant M~N~MUM VOLUME REOUIREMENT 1000 VEt-FHR SATISFIED ENTERINGVOLUMES-_ALLAPpRDACHES ~~ OR UN vEeR DURING EACH OF ANY 5 HRS. OF A SAT. AND~R~ .... ~ CHARACTERISTICS OF MAJOR ROUTES MAJOR ST. HWY. SYSTEM SERVING AS PRINCIPLE NETWORK FOR THROUGH TRAFFIC RURAL OR SUBURBAN HWY OUTSIDE OF. ENTERING, OR TRAVERSING A CITY ' APPEARS AS MAJOR ROUTE ON AN OFFICIAL PLAN MINOR ST. YES [~ NO [] FULFILLED YES NO [] ANY MAJOR ROUTE CHARACTERISTICS MET, BOTH $3'REETS The satisfaction of a warrant is not necessarily ]ustlficatlon tora signal. Delay, congestion, confuslon or other evidence o! the need for right-of-waY asslgnmnent must be shown. 9-8 1-1991 II TRAFFIC SIGNALS AND LIGHTING III I I IL I ! Figure 9-3 TRAFFIC SIGNAL WARRANTS Traffic Manual WARRANT 8 ,. Combination of Warrants SATISFIED YES [] NO REQUIREMENT" WARRANT ,/ FULFILLED TWO WARRANTS 1. MINIMUM VEHICULAR VOLUME SATISFIED 80% 2. INTERRUPTION OF CONTINUOUS TRAFFIC YES [] NO ~] WARRANT 9 - Four Hour Volume SATISFIFD* YES [] NO [~[ Approach Lanes One more Highest Approaches Minor Street ~ r ~' (~\' ~)~ d)~\ Refer to Figure 9-6 (URBAN AREAS) or Figure 9-7 (RURAL AREAS) to determine if this warrant is satisfied. WARRANT - Peak Hour Delay (ALL PARTS MUST BE SATISFIED) SATISFIED YES [] NO .~ I. The total delay experienced for traffic on one minor street approach controlled by a STOP sign equals or exceeds iour vehicle-hours for a one-lane approach and f'rve 'vehicle-hours for a two-lane approach; ~ 2. The volume on the same minor street approach equals or exceeds 100 vph for one moving lane of traffic or 150 vph tor two moving lanes; AND YES [] NO P~ YES [~ NO []- The total entering volume serviced during the hour equals or exceeds 800 vph for intersections with lout or more approaches or 650 vph for intersections with three approaches. YES [~ NO [] WARRANT 11 - Peak Hour Volume SATISFIEP* YES [] NO ~ Approach Lanes One more ?~\ I\Q%\ ur '* Refer to Figure 9-8 (URBAN AREAS) or Figure 9-9 (RURAL AREAS) to delurmine if this warrant is satisfied. The satisfaction of a warrant is not necessarily justification for a signal Delay, congestion, confusion or other ay]dance /'-'. !".'- of the need for right-of-way assignment must be shown. '-'"" TRAFFIC SIGNALS AND LIGHTING II I I lllll Figure 9-7 FOUR HOUR VOLUME WARRANT (Rural Areas) Traffic Manual 0 3~ 400 300 2OO 100 .-----2 OR MORE LANES (MAJOR) 2 OR MORE LANES (MINOR) '~~ 2 OR MORE LANES (MAJOR) & 1 LANE (MINOR) OR 1 LANE (MAJOR) & 2 OR MORE LANES (MINOR) I LANE (MAJOR) & 1 LANE (MINOR)~'-'-'~ 200 300 400 500 60D 700 800 900 1000 MAJOR STREET o TOTAL OF BOTH APPROACHES - VPH NOTE: S0 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACH WITH TWO OR MORE LANES AND 60 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACHING WITH ONE LANE. Traffic Manual TRAFFIC SIGNALS AND LIGHTING II I I Figure 9-6 FOUR HOUR VOLUME WARRANT (Urban Areas) g co n- O 500 400 300 200 100 0 300 %~,...,~...-' "-~.2 OR I~ORF_ LANi:::$ (MAJOR) & 2 OR I'AOR~' LANES (MINOR) I! I *~. ~.. I I I i I I ~2 OR MORE LANES(MAJOR) & 1 L~NE (MINOR) ~ ~ OR 1 LANE (MAJOR) & 2 MORE LANES (MINDR) 1 LANE (MAJOR) & 1 LANE (MINOR) ----- I t ! 1,, , 400 500 600 700 800 900 1000 1100 1200 1300 1400 MAJOR STREET - TOTAL OF BOTH APPROACHES - VPH NOTE: 115 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACH WITH TWO OR MORE LANES AND 80 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACHING WITH ONE LANE. 9-14 TRAFFIC SIGNALS AND LIGHTING Figure 9-9 PEAK HOUR VOLUME WARRANT (Rural Areas) Traffic Manual 500 400 3OO 2O0 100 0 300 ---- 2 OR MORE LANES (MAJOR) & 2 OR MORE LANES (MINOR) '~~ 2 OR MORE LANES (MAJOR) & 1 LANE (MINOR) ~ ~.~'"~' OR 1 LANE (MAJOR) & 2 OR MORE LANES (MINOR) LANE' (blAJOR) & 1 LANE (M~NOR) - 400 500 600 700 BOO 900 1000 1100 1200 1300 MAJOR STREET - TOTAL OF BOTH APPROACHES - VPH NOTE: 100 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACH WITH TWO OR MORE LANF.$ AND 75 VPH APPLIES AS THE LOWER THR:..$HOLD VOLUME FOR A MINOR STREET APPROAC;H[NG WiTH ONE LANE, Traffic Manual TRAFFIC SIGNALS AND LIGHTING mai Il I Figure 9-8 PEAK HOUR VOLUME WARRANT (Urban Areas) 600 l" J i i ~" I I i '1 - .----- 2 OR MORE LANES (MAJOR) & 2 OR MORE LANES (MINOR) -r /...~--!--- 2 OR MORE LANES (MAJOR) & 1 LANE (MINOR) ~' '~, ,../'~'~"("~ OR 1 LANE MAJORJ & 2 OR MORE LANES (MINOR) >, 500 ~ , o ~ 400 ~ ~OO o 200 (5 ~' ~""~ "-- ,' I '": E. 100 / 0 ~ ,, I I .] I I .... 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 I~'~JOR STREET - TOTAL OF BOTH APPROACHES - VPH NOTE: 150 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACH WITH TWO OR MORE LANES AND 100 VPH APPLIES AS THE LOWER THRESHOLD VOLUME FOR A MINOR STREET APPROACHING WITH ONE LANE. RESOLUTION NO. - 97 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DUBLIN ESTABLISHING NO PARKING ZONE ON ~ NORTltERLY CURBLINE OF DUBLIN BOULEVARD EASTERLY OF }tANSEN DRIVE The City. Council of the City of Dublin hereby resolves as follows: Section 1' Pursuant to City of Dublin Municipal Code Section 6.04.250, and in the interest of public safety, a No Parking Zone is established on the northerly curbline of Dublin Boulevard, from the easterly curbline of Hansen Drive, easterly a distance of 210 feet. Section 2. Said No Parking Zone shall be added to Section 6.28.010 of the City of Dublin Traffic Code. PASSED, APPROVED AND ADOPTED this 20th day of May, 1997. AYES: NOES: ABSENT: ABSTAIN: ATTEST: Mayor gSagenmisckresodubh City Clerk -E,×H!BJT oo