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Home My WebLink AboutCOM 0590.000 2010-2012 tPJMty of y��••••• William P. Kenoi • *. '" :+ - Warren H.W. Lee •Mayor Director William T.Takaba 4T�,oF Brandon A.K.Gonzalez Managing Director Deputy Director IiiunYf r of Ra a:'i DEPARTMENT OF PUBLIC WORKS Aupuni Center 101 Pauahi Street,Suite 7•Hilo,Hawaii 96720-4224 (808)961-8321 •Fax(808)961-8630 www.co.hawaii.hi.us FEBRUARY 1, 2012 HONORABLE CHAIRMAN DOMINIC YAGONG vt AND MEMBERS OF THE HAWAII COUNTY COUNCIL HAWAI'I COUNTY COUNCIL 1a• HILO HI 96720 SUBJECT: TRAFFIC CODE AMENDMENT: SECTION 24-265 — REVERSE YIELD DIRECTION AT ONE-LANE BRIDGE We request the Hawai'i County Code, Chapter 24, Article 10 (Schedules), Division 2 (Moving Vehicles), Section 24-265, Schedule 13 (Yield locations), paragraph (a) (Hamakua) be amended by revising existing item: (11) Kalopa Road, castWESTbound approach to bridge adjacent to parcels 4-4-2:5, 4-4-2:6, 4-4-9:3, and 4-4-9:8. The reason for this amendment is to reverse the yield direction to provide improved sight distance and added safety for crossing the bridge. Location map, sight distance study summary and photo's are attached for your reference. APPROVED (7Firsix..74) Warren H.W. Lee William enoi Director of Public Works Mayor RLT/ATT cc: TRF Public Works Committee Chair (w/attach) Chief of Police Comm No. c90 Ref. To: W ( U .(�• R1 bill I "I3 ) County of Hawai'i is an Equal Opportunity Prop ider and Employer. ef. Date FEB 1 201 t *• oR 17 a Q) F MO W 73 K V1 LC * L Q J ♦ O w 0 a r "t • 9e to V al of s r; II KO .. te i a4 / •h''h '.%'''.;'-'-'-''-h'-.7"7,r4- : ;'''' I .— i «r a C • N r % 3 r P,TH * i 0 .fir! s .A } F E� ui t c �- . ,;q r)i b*' 0 ' +1., r.» g yp ' .n s. / ,F�.n.., .. x_.-. +,, r w 0 I -0 E hh,a �S 9'. y - 0 CL t a1 O co - - � ' •William P. Kenoi % +:R!`"�'%��'+% Warren H.W. Lee Mayor _ Director • William T.Takaba Brandon A. K.Gonzalez Managing Director Deputy Director Couttti of Paimil DEPARTMENT OF PUBLIC WORKS Aupuni Center 101 Pauahi Street,Suite 7•Hilo,Hawai`i 96720-4224 (808)961-8321 •Fax(808)961-8630 www.co.hawaii.hi.us February 1, 2012 TO: File SUBJECT: ONE LANE BRIDGE SIGHT DISTANCE STUDY FOR YIELD LOCATION Kalopa Road bridge fronting parcels 4-4-2:5, 4-4-2:6, 4-4-9:3, and 4-4-9:8 BACKGROUND INFO: Per the Manual on Uniform Traffic Control Devices (MUTCD), "The YIELD sign assigns right-of-way to traffic on certain approaches to an intersection. Vehicles controlled by a YIELD sign need to slow down to a speed that is reasonable for the existing conditions or stop when necessary to avoid conflicting traffic." The use of a yield sign would be appropriate on a one lane bridge because a full stop is not always required and would give clear indication as to who has the right-of-way should two-way traffic approach the bridge at the same time. ONE LANE BRIDGE STUDY DATA: Prior to assigning right-of-way on a one-lane bridge, there are two sight distance measurements that Traffic Division verifies and studies. These measurements help to determine which side would be best for the yield condition. The first sight distance check is the stopping sight distance for a yield condition. This would be the distance required by each driver to see an oncoming car to allow the driver to stop prior to entering onto the bridge. For the 25 mph hour case, this stopping sight distance would be 115'. The total distance a driver would need to see across would be d1=115'+length of bridge+115'. See detail 1 — sight distance check #1 for more info. The second sight distance check is the sight distance needed for a driver at the yield bar to safely clear the bridge. We base this on timed samples of drivers going across the bridge at a safe speed. The formula for this distance is d2=1.47*(time to cross bridge)*25 mph+bridge length. For the subject bridge, the sight distance would be d2=1.47*(9 sec.)*(25 mph) = 330.75'+bridge length. See detail 1 — sight distance check #2 for more info. County of Hawai`i is an Equal Opportunity Provider and Employer. Sight Distance Study at One Lane Bridge cont'd 2/1/2012 FINDINGS AND RECOMMENDATION: During Traffic Division's initial site visit on 10/14/11, assuming the yield would be for eastbound (makai bound) traffic, stopping sight distance was met, but the sight distance to clear bridge from the yield bar was not met. The sight distance measured to clear the bridge was 160', which is significantly less than the required 330.75'+bridge length. It was recommended by the technicians that conducted the sight distance study that we reverse the yield direction from eastbound to westbound due to the better line of sight provided for westbound traffic. The line of sight was improved due to the vegetation clearing that the Highways Division did at the bridge. No formal follow-up study was conducted, but a visual check of the westbound line of sight established that there was adequate sight distance to clear the bridge on this side. The Traffic Division's recommendation is to reverse the yield direction from eastbound to westbound. ATT County of Hawai'i is an Equal Opportunity Provider and Employer. b • STOPPING SIGHT ONE LANE TY DISTANCE FOR BRIDGE YIELD CONTROL POSTED La or Lb SPEED (ft) Lb' (mph) S(atir Cainivvve= c-btcf. 411 : d, Lb 15 70 • 20 90 rpleN`' 614+11- 1014frANC# r 25 115 '1 i 0.-P Go-JP pry) . 30 142 ASS0401 : Sppp U�rr , 25 bur 0 35 171 I 40 203 LA t Lb ((5 BL 45 236 d. z (%5� + 15L. + I,Is 50 271 I co t V I/ f °f X44.11- 55 307 (NPrI7 AASHTO "Green Book" pg. 658 & 670. rFc*^ I .i,4T rb Assume reduction to 60% of midblock speed. (/ - (lig.° NI...yr- YIELD ccv VVV Q ITO ONC OMING TRAFFIC La a • Sint-t Pirr ctrr Z d1 • 4 V t ;. 1 S Li: : 1.41-] (.'5.011p)(1) ONE LANE r. 330.15 / BRIDGE 1.x : L b' -1- 13L OrrAt4 I c.,,,,v„:,„,,,, BRIDGE SIGNS AND STRIPING STANDARD 4\:-.1 0• COUNTY OF HAWAII TR-03 DETAILS 5;.:;i;,; APPROVED: DATE: 7/18/08 or x� TDAmr nnncinni Cr AI F- 1"-dfl' blue � $ t w . I i a„- „ (r a y xf �«4 r � • roNsv T J Photol -Eastbound prior to clearing N O ■ N S T o �'* E �+ g W N -cs l J I g it R o .I a cc : f s o 1 co t SI _ O �. ;:::1-1"i". U Td 3 e a .yy I CU W i VI C S 'O 'a -may, 3 U 4_i Z e� ° 3' rn IN.. ,,. > = E ^` L) 2 O W p 5. c 1 \ o I ; O mLL c 7 L a' O Li:I it' CD CO 1 I N I 1 1 r't" I e l O - ti ,'"1 w ' : 11','11,',Y 4 q s'^ Cf< r « ` r, . Oi A ,\ '; � ' <. o A Ii, ; 0 S r\\ f :,; 4 w lio ? 0 ,r r' rR^ 2 �'i ��R A ysa,r� • 'Er-,, a ` U a O 6 ��t Cl)j c� t § Wp • - 8 ak U a x .: 2 1 a* e .— , *lr �ss 0•-L I 4 ,.r ,r' ef ( O/ez J j i(y _•�� •f p 1 9 E p il�` 1 r 0 t g, L E �?" 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