ASCE HPT UPDATE FEBRUARY 2000

From: Mac Elliott mac.elliott@home.com
2530 San Elijo Ave. Cardiff, CA 92007
tel(and fax on request) 760)-944-7324

HPT Website. http://www.ascehpt.homestead.com

TO All ASCE Human Powered Transportation Committee (HPT Com) Members & Friends.

1. Shoulder Rumble Strips: Action continues.

1!a. Darrin Torbic 814-863-5472 reported Penn State Univ rumble strip tests completed. Recommendations for milled-in depressions 5" wide in direction of travel by 3/8" maximum depth, at non-freeway shoulders, sent to Penn DOT Feb 16.

1b. Troy Bucko 916-654-3917 reported Caltrans will have Interim Report on their Rumble Strip testing out in March. Tested motor vehicles to date. Will test bikes when roads clear later in spring. Plan to test milled-in and other patterns as well.

1c. Jim Growney 518-431-4224 stepping down as FHWA lead for rumble strips. Replacement not named yet..

2. Roundabouts: David Harkey chaired excellent Seminar on Roundabouts at January TRB meeting in Washington.. Some notes follow:

2a. Bicycle Basics at Roundabouts:

(1) Bike lanes inside circle are dangerous because cyclist is too far right, and overtaking motorist may expect cyclist to use next exit. Cyclists not exiting may be struck by exiting motorist. Also, right of way is not always clear to entering motorist, who may not have had to yield to peds and may not yield to circulating cyclist.

(2) For above reasons, cyclist must often merge with circulating traffic in order to safely pass an exit.

(3) If bikes are to safely negotiate roundabouts inside the circle, traffic speeds must be slow enough (12-15 mph), for cyclists to merge, unless traffic volumes are low. Greater than 20 mph requires expert cyclist to safely merge.

(4) If roundabout contains more than one traffic lane, cyclist is placed at risk by multiple merging and crossing traffic movements. Particularly hazardous are two laned exits, (which are illegal in Germany).

(5) Therefore, if roundabouts contain more than one lane, or have circulating speeds exceeding 15-20 mph, or have high volumes, (greater than 8,000 vehicles per day in Netherlands), cyclists usually must be routed around exterior, similar to pedestrians.

2b. Pedestrians generally have right-of way within crosswalks, but it's not always clear that motorists are yielding, particularly on the exit leg. Entry leg not as much of a problem, since motorists are preparing to yield at roundabout anyway. Not always clear to motorist whether ped will cross exit leg or yield. Exit leg is particularly hazardous for peds crossing in counterclockwise direction, as exiting car approaches from behind ped's left shoulder.

2c. Primary issues for visually impaired at roundabouts are: 1) Lack of good guidance assistance in finding the appropriate crossing location, and 2) loss of directional cues to be able to know when there is gap in traffic. The latter sometimes results in having to wait for NO traffic in roundabout and can result in extreme delays.

2d. Werner Brilon of Germany spoke. Knowledgeable re European roundabouts. Brilon comments follow.

(1) Mini Roundabouts very popular. Small, with traversable center island. Cheap, Requiring Only Paint. Easy to convert existing 4 way intersection, .Very safe. Volumes up to 17,000 per day.

(2) Compact Roundabouts, (Small, single lane, with entrances and exits almost right angle and of small radii , center islands NOT fully traversable). are also generally no problem for peds, children, elderly, etc. in Germany. Holland also uses these designs

(3) France installing many small roundabouts. Appear widely accepted.

(4) Britain has 20,000 roundabouts. Germany 15,000. France over 10,000. British are larger and faster. Not as safe for bikes & peds.

(5) 3 arm roundabouts have high speed problems. (Tangential entries & exits).

(6) Bikes are 1st to suffer from poor roundabout design.

(7) Overall traffic speed and roadway capacity is not reduced if roundabouts are spaced more than than 1,000 meters apart.

(8) In Germany, single lane roundabouts can handle volumes up to 25,000 per day without signals. If volumes exceed 25,000 they don't use roundabout, because multi-lanes too dangerous both for motorist and for cyclist. i.e. Germany does not use multi laned roundabouts.

(9) A very important comment by Brilon: "Regardless of what experience shows in other countries, we must be very careful NOT to assume it will work as well here. Differences in road-user behavior often lead to problems with transfers of designs and technologies."

2e. A presentation was given on new Clearwater Beach Florida roundabout. See Item 3 below for on-site report and problems.

2f. FHWA Roundabout Informational Guide, 200 pg, available in March. On internet at www.tfhrc.gov Can request book and CD-ROM versions by faxing 301-577-1431. Copies will be mailed when published.

3. Elliott observed new Clearwater Beach (Fla) Gateway Roundabout on Jan 13. Large, oval, 6 armed roundabout designed for 40,000 vehicles per day, design speeds 18-20 mph. 2 circulating lanes. Of considerable interest in U.S., due to its "state of the art" design, "grand entryway to beach" location, architectural and aesthetic features, etc. Opened Dec 1999. It seems to have some real problems.

Elliott did not have time to measure lane widths, curve radii, or other geometry, but witnessed several near misses and awkward merging and crossing maneuvers on a light traffic weekday early afternoon. Sight distances seemed short. Often difficult to enter circle, or to get into or out of proper lane. Truck wheels climbed over curbs and splitter islands when making exits. Ped crossing required care, particularly going counterclockwise, (but could be done). Same with bikes, which used ped crossings.

Citizen reaction is highly negative, as judged both by numerous Letters to Editor (all negative, none positive in Jan 14 North Pinellas Times), and by speaking with local residents. Roundabout is main entry to Clearwater Beach, and cannot easily be avoided. Typical comments were: "Circle too small and lanes too narrow to handle traffic, creating lengthy peak hour backups". - "Ped crosswalk too close to circle, creating hazards for peds and also stoppages in circle caused by cars backed up for peds". "Massive raised concrete center island fountain obstructs entering motorist's view of circulating traffic & gives insufficient time to make safe move into proper lane". - "Palm trees block view of peds and traffic." - "With constant tourist turnover and new users, roundabout may never develop a beneficial user-learning curve", etc.

Engineers can learn much when problems surface. It would seem prudent for planners and designers of new roundabouts to study Clearwater Beach. Would also be instructive to compare pertinent details of this roundabout with FHWA's new Guide (Item 2f), to see if Guide would have prevented some of the problems. See also Werner Brilon comment, Item 2d(9), regarding caution in transferring designs..

4. "Sustainability" was big at TRB. Sessions on sustainability were jammed, while sessions on bikes and peds per se were not as well attended.. (Henry Hatch, ASCE's Chief Operating Officer, on target all along with his emphasis on sustainability)

4a. European Union has "Sustainable City of the Year" Award. Groningen (120,000 pop, serves 1,500,000), is a Winner. 50% bike commuting. Has only limited car parking. Prohibits out of town malls. 1-way streets used 2 ways by bikes. Large public support for plan. 3 requirements for success were Determination, Maintaining dialogue, and Integrated Approach.

4b. Zurich also Award Winner. Emphasizes public transit. 37% transit, 28% car, and 35% bike & walk. All street cars remain at street level, where the people are (no subways). 10 minute headways.

4c. Car Sharing becoming more common in Europe. 40 car sharing companies in 300 cities. Membership in car sharing company gets you a smart card. Touch window with card and door opens. You only use car when you need it and are charged when you use it plus a monthly fee. Edinburgh residential project requires residents to sign agreement not to own car. All residents belong to car share company.

4d. Can contact Elliott for copy of 3 pg article from CROW, the Dutch organization that produces guidelines for bike and ped facilities in Holland. (1999 TRB paper on sustainable transp systems in Holland and 2 cities in Germany and Denmark)..

5. FHWA College Bike & Ped Course: Carol Tan Esse (202-493-3315) presented draft of introductory 1 hour slide show. Hope is to adapt this as 1 hr stand alone bike-ped lecture for inclusion in regular college transp engineering course. Carol collecting additional slides.

6. David Harkey reported on FHWA Ped & Bike Info Center operated by Hwy Safety Research Ctr (HRSC) at Univ of N Carolina. Websites <www.walkinginfo.org> and <www.bicyclinginfo.org> are intended for use by both professionals and general public. A toll free 877-WALK BIKE number is intended to provide technical assistance to the professional only. Topics to include policy & planning, design & engineering, education & enforcement, rails & trails, crashes, transit, research & development, community problems & solutions, outreach & promotion, health & fitness. Also developing digital library to include ped & bike images related to above, and Harkey would appreciate receiving pertinent slides, photos, illustrating good & bad practices. <david_harkey@unc.edu> or 919-962-8705 .Also developing & teaching a series of Ped Audit courses. Working with Assoc of Ped & Bike Professionals (APBP)

7. New AASHTO Ped Facility Guide: Plan of project team, led by John LaPlante , to complete guide was approved Feb 1. Draft version scheduled for mid-June. Revised version based on reviewers comments expected Sept or Oct. Completion by end of year.

8. Gihon Jordan District Traffic Engr of Philadelphia reported positive results with tests of limited paint striping centerlines of multi use paths at intersections & blind curves. Solid yellow centerline striping starting 30 to 50 feet on either side of blind curves and continuing thru the curve resulted in 57 % reduction in wrong side travel or incorrect passing. Solid white centerline striping for 30 feet each side of road intersections, with four 1 ft dashes alternated with 3 ft gaps added to the pathway ends of the solid lines, reduced incorrect behavior by 66 %. Painted directional arrows 18" long by 12" wide, were used in each lane at each end of blind curves and at each side of intersections. Gihon recommends further research to more fully explore problem & treatment.

9. Good Traffic Calming Basics article in Jan 2000 'Civil Engineerng' magazine. Contact Elliott for copy . Reference "Canadian Guide to Neighborhood Traffic Calming," <http://tac-atc.ca/index:htm> Also ITE website <www.ite.org/traffic> for info.

Speed humps are often used in Portland OR now instead of traffic circles. Humps reduce speed between intersections. Portland uses 14 ft long x 3 inch high parabolic humps instead of 12 ft long, which they found too abrupt. Also use 22 ft long humps on higher volume streets. Also experimenting with removable rubber humps for temporary use at construction zones, etc.

Mac Elliott

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