NEW YORK STATE DEPARTMENT OF TRANSPORTATION Roundabouts Status
NEW YORK STATE DEPARTMENT OF TRANSPORTATION
Roundabouts Status within NYSDOT
Roundabouts in New York State Total Number is at Least 64 * 45 on the state system * 19 off the state system 46 are single laners 7 are major-minors 11 are 2 laners No 3 laners yet No minis currently – had 1 in the state but didn’t make it more than a month or so… New York has at least 90 in design throughout the state
New York Roundabouts – Single Laners North Haven(01) single laner that was to be 1 of 2 Rochester single laner on RIT campus (03) Great Neck (03) single laner that replaced signalized circle Voorheesville (03) single laner that replaced yield “Y” Greenwich (04) single laner that replaced signalized “T” Ithaca single laner off state system (04) Plattsburgh (04) single laner that replaced signalized 4 -way Liberty (2) single laners off Exit 100, I-86 (06) Cortlandt Manor(06)single laner that replaced signal Huntington (02) single laner used for traffic calming Rochester (05) single laner w/ raised pedestrian crossing
Common Unrealistic Objection – Large Trucks 75’x 13’ Modular Home Takes Left at Greenwich, NY Roundabout
…New York Roundabouts – Single Laners Mt Vernon (06) single laner with fountain and music Mendon (06) single laner with center light; hi-speed Stony Brook, LI(06) single laner on campus roadway Poughkeepsie (3)(06/08) single laners near Vassar College Bethlehem (07) Bainbridge (07) single laner that replaced a 3 -way stop single laner just off I-88 exit w/NY 206 Hamburg (4) (07/08) urban single laners made of 100% PCC Westchester Airport (06) access to local airport Westhampton Beach (06) oval single laner at former 6 corners Eastern LI (07) local intersection designed by Mc. Lean Colonie Center (07) access to mall from town road Glens Falls (07) 5 legs in urban, downtown environment
Glens Falls – 5 leg urban - downtown
…New York Roundabouts – Single Laners Malta (08) single laner for Round Lake Bypass Cohoes (08) single laner at 3 corners Niagara Falls (07) single laner on Rainbow Boulevard Malta (2) (08) single laners on Dunning St. for Tech Parks Buffalo (2) (08) single laners that are only 100’ apart Caledonia (05) resigned & restriped traffic circle Batavia (09) single laner @ 33/98 Latham (09) Old Wolf @ Old Nisky Rotterdam (09) single laner @ 7/146 Irondequoit (4)(09) single laners (mostly) at end of 590 Chatham (09) small single laner Aurora (09) resigned and restriped single lane circle
2 Roundabout Solution Recently Completed Harlem Road at Kensington Ave and Wehrle Drive
…New York Roundabouts – Major/Minors Kinderhook (05) 2 laner for SB direction only, 5 legs Buffalo (08) Harlem/Cleveland Road Corning (2) (03) access permits for R & D plant Latham (02) resigned & restriped traffic circle Griffiss (02) major-minor done in old air force base Round Lake (09) major-minor @ Rt 9/67
Latham Traffic Circle Retrofit - Before
Latham Traffic Circle Retrofit - After
Latham Multi Lane Approach – Before Alignment, Signing & Striping
Latham Multi Lane Approach – After Alignment, Signing & Striping
New York Roundabouts – Two Laners Kingston (00) 2 laner that replaced traffic circle Malta (5) (06) 5 total in a ¾ mile corridor Johnson City (05) 2 laner & flyover that replaced traffic circle Slingerlands (4) (07) 4 total in a 1. 5 mile section of new hwy
Malta now has 7 in a row…
New York Roundabouts – In Construction or maybe finished Colonie major-minor at Albany-Shaker & Maxwell Buffalo (2) major-minor on Outer Harbor project Brockport single laner that may be awarded? ? ?
…New York Roundabouts – In Final Design Malta (2) a single & major-minor for AMD Monticello single laner @ 104 off 17 B Mayfield major-minor @ 29 & 30 East Greenbush Route 4 @ 151
…New York Roundabouts – In Design Auburn railroad right thru center island Cicero Onondaga County project Glenville Maple @ Glenridge Road Huntington (2) Rt 110 near school for the blind
Roundabouts Lessons Learned the Hard Way
Traffic Circle vs. Roundabout Kingston Traffic Circle Under Construction to become a Roundabout
Kingston Roundabout Striping If you sign & stripe it like a single lane – SURPRISE!
North Haven on Long Island – Design Vehicle?
North Haven on Long Island – Design Vehicle? WB-50
North Haven on Long Island – Design Vehicle? WB-67 WB-50
Rome – Former Griffiss Air Force Base What’s wrong with the truck apron?
Winter Plowing can still be a challenge
Roundabouts Policy at NYSDOT
Draft HDM Chapter 26 § Based on FHWA Guide § Presently 103 pages – should be around 20 when done § Alterations / additions to FHWA guide: § Standard left turn arrows on approaches removed § Both sharks teeth and dashed line used § Two lane roundabouts striped § Truck aprons required for multi-lane roundabouts § WB-67 is default design vehicle § Lane by lane capacity analysis required § Critical gap reduced for intersection sight distance
HDM Chapter 26 § Should be released later this year – for 5 years running § NYSDOT is still finalizing standards for a few roundabout topics – primarily: visually impaired accommodations § NYSDOT now requires that roundabouts be considered whenever an intersection is being evaluated for capacity or safety improvements, and if determined feasible than it SHOULD be NYSDOTs preferred intersection by default § Many other states already have similar policies recommending roundabouts… … more states to follow.
NYSDOT HDM Chapter 5 – Policy as of 8/23/06
FHWA Field Memo – July 10, 2008 Consideration and Implementation of Proven Safety Countermeasures GUIDANCE STATEMENT: “Roundabouts are the preferred safety alternative for a wide range of intersections. Although they may not be appropriate in all circumstances, they should be considered as an alternative for all proposed new intersections on Federally-funded highway projects…” 32
Future Concerns § Funding! § Oversized Vehicles – especially for the wind farms § Visually Impaired Pedestrian Accommodation – ADAAG - Liability § All 2 lane crossings are likely to require some form of signalization – HAWK or hybrid, RRFB … § Likely going to make 2 lane roundabouts harder to put in just based on cost increase: +/- $250 K per rbt § 2019 Compliance Date?
Roundabouts Changes over the years at NYSDOT
Design Steps and Capacity Analysis § Design § Offset Left now preferred over radial § “Streamlined & simplified” process § Capacity Analysis § Was geometric specific (RODEL ONLY) § Now lane-by-lane (SIDRA & VISSIM) Note: I will elaborate on capacity tomorrow morning
2000 FHWA Recommendations
Offset Left Now Preferred by NYSDOT & Other Organizations
Central City Roundabout - Radial
Central City Roundabout – Offset Left
Design Steps 1 ST – place 150’ diameter circle at center of existing intersection. All work being done at this point is with paint lines – curb lines are just offsets from the paint lines
Design Steps 2 nd – copy 150’ diameter circle parallel around 18’ or so twice – once for the travel lane and another time for the truck apron NOTE: later you will need to check with Auto. Turn, Auto. Track or a similar program
Design Steps 3 rd – use a 300’ to 800’ fillet to tie the center line to the exit side of the truck apron and the left edge line to the outside of the roundabout – use the same radius to let CAD worry about the taper. .
Design Steps 4 th – copy the new center line over 12’ for your new right edge line
Design Steps 5 th – use a 90’ to 110’ fillet to tie in the approach. Use the same radius on both sides – let CAD take care of the taper…
RESULT One leg is done – you now have an approach with geometry that requires vehicles to slow down before the yield line. This technique has 2 points of speed reduction – you have staged and staggered the speed reduction
The NYSDOT Roundabout Design Unit would like to thank everyone for their attention this morning…
NYSDOT Roundabout Design Unit Contact Information Howard Mc. Culloch, Richard Schell, PE Michael Houlihan, Greg Bailey and Tom Kligerman, PE Roundabout Design Unit 50 Wolf Road, POD 24 Albany, New York 12232 Tel: (518) 485 -7503 Fax: (518) 457 -2916 E-mail: roundabouts@dot. state. ny. us
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