Parisi TRANSPORTATION CONSUtllHG

Transcription

1 Attachment 1 To: Jonathan Goldman, P.E., QSD, CFM From: Cc: David Parisi, P.E., Curt Harrington, E.l.T. Andrew Davidson, P.E. Date: June 6, 2016 Subject: Bridgeway - Uncontrolled Crosswalk Tool and Location Recommendation Parisi Transportation Consulting (Parisi), on behalf of the City of Sausalito (City), has prepared this memorandum to summarize the comparison between potential uncontrolled crosswalk tools (rectangular rapid-flashing beacon vs. in-street flashers) and to select an initial location on Bridgeway for deployment of such tools. Concepts for the recommended tool (RRFB) and crossing location (Bridgeway at Napa Street) are also provided. In-Street Flashers vs. Rectangular Rapid-Flashing Beacon (RRFB) RRFBs Compliance A common question amongst jurisdictions over recent years is why the installation of a RRFB system is more effective and safe than in-street flashers as an uncontrolled crosswalk treatment. Per the Federal Highway Administration, "An Analysis of the Effects of Stutter Flash LED Beacons to Increase Yielding to Pedestrians Using Multilane Crosswalks," along with "The Use of Stutter Flash LED Beacons to Increase Yielding to Pedestrians at Crosswalks," presented at the Transportation Research Board Annual Meeting in 2008, summarized the results of two studies on the effects of RRFBs when used to supplement standard pedestrian crossing warning signs at crosswalks. The former found that going from a no-beacon arrangement to a two-beacon system, mounted on the supplementary warning sign on the right side of the crossing, increased yielding from 18 percent to 81 percent. There was a further increase in yielding behavior, with a four-beacon system (with two beacons on both the right and left side of the crossing) to 88 percent. "An Analysis of the Effects of Stutter Flash LED Beacons to Increase Yielding to Pedestrians Using Multilane Crosswalks" also evaluated the sites over a 1-year period, and found that there was little to no decrease in yielding behavior over time." Including RRFBs on the roadside increases driver yielding behavior significantly. Including RRFBs on a center island or median as well can further increase driver yielding behavior. Parisi TRANSPORTATION CONSUtllHG Page 1 of 8

2 Attachment 1 Bridgeway - Unconlrolled Crossing Recommendalion Maintenance RRFB systems can often be implemented using solar power rather than directly connecting into a hard-wired power source. Pedestrian push buttons installed with the RRFB can be integrated into the system via wireless control, reducing the likelihood of vehicle disturbance of the system. In-Street Flashers Compliance Motorist yielding compliance was studied in a literature review as a part of Turner, Fitzpatrick, Brewer, and Park's "Motorist Yielding to Pedestrians at Unsignalized Intersections". After compiling data from 11 various locations with actuated in-roadway warning lights, the average yielding compliance rate discovered was 66%. Maintenance In-street flashers are installed by cutting into the roadway to connect electrically to the nearest available power connection. They are generally an ongoing maintenance problem, often getting ripped up by large trucks. Nearby jurisdictions in Marin County have either abandoned damaged in-street flashers, or have transitioned to RRFB systems (e.g., Fairfax). Conclusion By comparing the FHWA yielding compliance rate of 88% for RRFBs (or higher for median RRFBs) to Turner's in-street flasher compliance rates of 66%, a greater or equal to 22% increase in compliance can be expected of RRFBs over in-street, a significant improvement in yielding compliance. This significant difference is due in part to the location of the flashing lights. RRFBs are at driver eye-level, whereas flashers are below driver eye-level and can be hidden by other stopped cars, causing a dual-threat scenario. In a dual-threat scenario, one car yields to a pedestrian, and the motorist in the adjacent lane does not stop because they do not see the pedestrian, whom is hidden by the stopped car. RRFBs at driver eye-level on both sides of the road reduces the likelihood of this occurring. It is recommended that an RRFB system is installed over in-street flashers, as RRFBs are a clear upgrade over in-street systems in yielding compliance and maintenance needs. Choosing Napa Street A detailed review of the Bridgeway corridor was conducted to locate the optimal location for the installation of an initial RRFB system. The existing uncontrolled crosswalk crossing Bridgeway at Napa Street ranked the highest for the RRFB upgrade. Bridgeway and Napa ranked highest in need for a RRFB installation given: The observed speed of traffic approaching the intersection (transition from a 35 mph to 25 mph speed limit heading towards downtown Sausalito), Roadway geometry (southbound traffic approaches on a horizontal curve), Complex intersection geometry (multiple turn lanes), 2 Page 2 of 8

3 Attachment 1 Bridgeway- Uncontrolled Crossing Recommendaiion Width of the pedestrian crossing (approximately 65' wide), High pedestrian volumes (between Caledonia Street and Dunphy Park), and Change in roadway character (southbound traffic entering a commercial district. Downtown Sausalito). Additionally, since it is the first uncontrolled marked crosswalk on Bridgeway for southbound traffic after traveling through a number of signalized intersections over the course of 1.25 miles, the intersection's crosswalk should be further enhanced. The provision of a RRFB system would remind drivers about pedestrian crossings at other downstream uncontrolled crosswalks. Concepts Attached are preliminary concepts that demonstrate the existing conditions and two potential RRFB concepts. The concept on page 2 of 3, a potential interim solution, would use the existing light poles for mounting the RRFBs and signs. The concept on page 3 is the recommended ultimate concept. In addition to the RRFB system, the concept provides a 6-foot wide pedestrian refuge island, which would also work as a "gateway" entrance. The island could potentially have attractive features, such as landscaping to match the existing channelizing island at Napa Street. There is existing room in the roadway for the island, by slightly shifting the left-turn lane to Napa Street. All turning movements were checked and approved with proper vehicle turning templates. Alignments for the through movements on Bridgeway would not need to be adjusted as a part of this concept. A double-sided RRFB would be installed in the new median, which would locate the rapid-flashers closer to the crosswalk and oncoming motorist's view. Single-sided RRFBs would be mounted to the existing streetlight poles on either side of Bridgeway. This concept style is preferred to the initial concept on page 2. Vehicle turning movement counts were completed in May of 2016 at the intersection. The left-turn volumes onto Napa Street are extremely low; there were not more than three vehicles making the turn during either the weekday AM or PM peak hours. 3 Page 3 of 8

4 Attactiment 1 \x Paris! TRANSPORTATION CONSULTING 1750 Bridgeway, Suite B208 Sausalito, CA (415) DP CH DP REVISIONS TOWN OF SAUSALITO - & NAPA STREET DATE SCAIE V' = 30' 05/27/2016 PTC PROJECT NO OENT town of sausalito Page 4 of 8 RRFB CONCEPT EXISTING CONDITIONS nr^nripiifmu 1 OF 3

5 TSIacRmenFT NOTES (7) INSTALL SINGLE-SIDED RRFB ON EXISTING STREET LIGHT INSTALL DOUBLE-SIDED RRFB ON EXISTING STREET LIGHT POLE 0 INSTALL "PED XING" PAVEMENT MARKINGS INSTALL YIELD LINE (TYP.) \x Page 5 of 8 OF

6 NOTES Q INSTALL 6' WIDE MEDIAN AND DOUBLE-SIDED INSTALL YIELD LINE INSTALL RRFB ON EXISTING STREET LIGHT INSTALL "RED XING" PAVEMENT MARKINGS (TYP.) \x Page 6 of 8

7 I KAi-NU UUUN I S PLUS mietekm@comcast.net Attachment 1 CITY OF SAUSALITO Proj. #16011 Latitude: Longitude: File Name : bridgeway-napa-a Site Code : 1 Start Date : 5/17/2016 Page No :1 Southbound Groups Printed- Vehicles Only NAPA ST Westbound Northbound NAPA ST Eastbound Start Time RTl TH LT U-turn App. Total RTl TH I LT App. Total RTl TH I LT App. Total RTl TH LT App. Total Int. Total 07: i i : i i : i 0 2 i 64 i 66 i : i Total : : : : Total Grand Total Apprch % Total % Southbound NAPA ST Westbound Northbound NAPA ST Eastbound Start Time RT 1 TH 1 LT 1 U-turn 1 App. Total RTl TH I LTl app.total RT I TH I LT 1 App. Total RT I TH 1 LT I app. Total Int. Total I Peak Hour Analysis From 07:00 to 08:45 - Peak 1 of 1 Peak Hour for Entire Intersection Begins at 08:00 08: : : : Total Volume % App. Total PHF Out In Total I 430l I 614l l RT 1 ^ TH LT U-turn i u Peak Hour Data T North t_?d CL < L O^J, Peak Hour Begins at 08:00 Vehicles Only > L 3 5 > cn ^ t LT TH RT I 3l 316l 9l I 4461 I 328l I 774! Out In Total RRIDOFWAY Page 7 of 8

8 I KAhNU UUUN I b PLUS mietekm@comcast.net Attachment 1 CITY OF SAUSALITO Proj. #16011 Latitude: Longitude: File Name Site Code Start Date Page No bridgeway-napa- 1 5/17/ Groups Printed- Vehicles Only NAPA ST NAPA ST Southbound Westbound Northbound Eastbound Start Time RT 1 TH LT 1 U-turn App. Total RT 1 TH LT App. Total RT I -ml IT App. Total RT I TH IT Int. Total 16: i i : i : : l Total : : : : Total Grand Total Apprch % Total % NAPA ST NAPA ST Southbound Westbound Northbound Eastbound Start Time RT 1 TH LT 1 U-turn App. Total RT tht LT I App. Total RT TH LT App. Total RT I TH IT Int. Total Peak Hour Analysis From 16:00 to 17:45 - Peak 1 of 1 Peak Hour for Entire Intersection Begins at 17:00 17: : i : : Total Volume % App. Total PHF Out In Total I 5501 I 6551 I l IE 1 RT TH LT U-turn <-i I u CO» rah^r Peak Hour Data T North Peak Hour Begin.5 at 17:00 Vehicles Onlv > 3 5 (f) *1 T r> LT TH RT I l 527) I 4501 I 9771 Out In Total RRinr^FWAY Page 8 of 8