I asked the NYC DOT about this last year and received the following
response:
[ Begin quoted text. ]
The purpose of these signals is to allow oversize emergency vehicles to
make U-turns to access the eastbound Belt Parkway. The bridge over the Paerdegat
Basin is not strong enough to support the weight of fire engines and other
emergency vehicles. If these vehicles need to respond to an emergency on the
eastbound Belt Parkway (east of the bridge) they can enter the westbound Belt at
Rockaway Parkway and U-turn in the eastbound direction. The signals and gates
(upon activation) will stop both directions of traffic on the parkway to
facilitate this U-turn.
[ End quoted text. ]
- Mr. Lyle Goldman,
Brooklyn, NY
The traffic lights were a stop gap measure, since the bridge was in
such bad shape. A half dozen 1939 era bridges are scheduled to be
replaced starting this fall, including the Mill Basin Br.
See http://www.nyc.gov/html/dot/html/bridges/reconstruction.shtml#7bridges
for more than you care to know about the Belt Pkwy bridges...
Ralph
Well it's about time.
- Mr. Lyle Goldman