The first time I got stuck at the 9th Street bridge in Gowanus, I couldn't quite believe it. Stopping traffic in New York City to let one boat pass? It seemed really quaint, but over the years I've gotten stuck there many times, mostly in the afternoons, and it's always kind of nice: a reminder of just how tied we (still) are to the water here. 

Since then, I've wondered how many bridges are left like this in the city, thinking there weren't more than a handful. Turns out there are still thirty movable bridges in New York, scattered around the boroughs and operated by different authorities. 

A few facts

Twenty six of the bridges are for motor vehicles; twenty five of which are operated by the Department of Transportation, and they have a great list with lots of history on their website. Three others are rail bridges operated by the MTA or Amtrak. And one's even a pedestrian-only bridge (the Wards Island Bridge.) The waterway with the most movable bridges? The Harlem River with eight. 

I was also struck by the variety of types of movable bridges in use —"drawbridge" is a misnomer for any of NYC's movable bridges, as we don't actually have any — but there are all sorts of other mechanisms in use, handily illustrated by Wikipedia with the animated gifs below. 

Bascule

Vertical lift

Swing

Retractile

gifs courtesy: http://en.wikipedia.org/wiki/Moveable_bridge#Visual_index_of_moving_bridges

The retractable bridge is my favorite of these, mostly because New York has two of the four remaining retractable bridges in operation in the whole country (the Carroll Street Bridge in Brooklyn and Borden Avenue Bridge in Queens). On the map, bridges are color-coded by these types.  

New York City's Movable Bridges: The List

Park Avenue Railroad Bridge 
Type: Swing
Source

Amtrak Pelham Bay Bridge 
Type: Bascule
Source

Spuyten Duyvil Bridge
Type: Swing
Operated by Amtrak
Opened approximately 1,000 times/year
Source

RFK Bridge - Harlem River Lift Span
Type: Vertical lift
Operated by the MTA
Source

Unionport Bridge
Type: Bascule
Total Cost: $5.4 million
Opened: Oct. 27, 1953
Source

Pelham Bridge
Type: Bascule
Total Cost: $605,274
Opened: Oct. 15, 1908
Busiest of all city-owned drawbridges
Source

Hutchinson River Parkway Bridge
Type: Bascule
Total Cost: $1.3 million
Opened: Oct. 11, 1941
Source

Eastern Boulevard Bridge
Type: Bascule
Total Cost: $2.8 million
Opened: Oct. 27, 1953
Source

Hunters Point Avenue Bridge
Type: Bascule
Total Cost: $108,985
Opened: Dec. 14, 1910
Source

Borden Avenue Bridge over Dutch Kills
Type: Retractile
Total Cost: $191,612
Opened: May 5, 1908
The Borden Avenue Bridge, along with the Carroll Street Bridge in Brooklyn, is one of the four remaining retractile bridges in the nation.
Source

Metropolitan Avenue Bridge over English Kills
Type: Bascule
Total Cost: $634,634
Opened: March 27, 1933
Source

Grand Street Bridge over the East Branch of Newtown Creek
Type: Swing
Total Cost: $205,671
Opened: February 3, 1903
Source

Greenpoint Avenue Bridge over Newtown Creek
Type: Bascule
Total Cost: $1.9 million
Opened: December 3, 1929
Source

Pulaski Bridge over Newtown Creek
Type: Bascule
Total Cost: $11.2 million (reconstructed in 1994 at a cost of approximately $40 million) 
Opened: Sep. 10, 1954
Source

Broadway Bridge over the Harlem River
Type: Vertical Lift
Total Cost: $13.4 million
Opened: July 1. 1962
Three tracks of the IRT subway are carried on its upper deck
Source

Willis Avenue Bridge
Type: Swing
Original bridge opened in 1901, at the same location of a 17th Century ferry.
Source

West 207th Street/University Heights Bridge over the Harlem River
Type: Swing
Total Cost: $1.2 million
Opened: Jan. 8, 1908
Source

Macombs Dam Bridge over the Harlem River
Type: Swing
Total Cost: $1.8 million
Opened: May 1, 1895
Oldest swing-type bridge in its original form in NYC.
Source

145th Street Bridge over the Harlem River
Type: Swing
Total Cost: $2.7 million
Opened: Aug. 24, 1905, reconstructed in 2007
Source

Madison Avenue Bridge over the Harlem River
Type: Swing
Total Cost: $2.1 million
Opened: July 18, 1910
Source

Third Avenue Bridge over the Harlem River
Type: Swing
Total Cost: $4 million 
Opened: August 1, 1898, reconstructed in 2004
Source

Wards Island Bridge
Type: Vertical Lift
Total Cost: $2.2 million
Opened: Oct. 11, 1941
Only movable pedestrian-only bridge in NYC
Source

Mill Basin Bridge
Type: Bascule
Total Cost: $1.4 million
Opened: Jun. 29, 1940
Source
This bridge is soon to become a fixed bridge.

Roosevelt Island Bridge
Type: Vertical Lift
Total Cost: $6.5 million
Opened: May 18, 1955, Only means of vehicular access to Roosevelt Island.
Source

Hamilton Avenue & the Gowanus Canal
Type: Bascule
Total Cost: $1.9 million
Opened: August 27, 1942, reconstructed in 2008-09
Source

3rd Street & the Gowanus Canal
Type: Bascule
Total Cost: $188,397
Opened: Mar. 31, 1905
Source

Union Street & the Gowanus Canal
Type: Bascule
Total Cost: $85,206.85
Opened: March 4, 1905
Source

Marine Parkway-Gil Hodges Memorial Bridge
Type: Vertical lift
Year built: 1937
Operated by the MTA
Source

Carroll Street & the Gowanus Canal
Type: Retractile
Total Cost: $36,742
Opened: 1889
Source

9th Street & the Gowanus Canal
Type: Vertical Lift
Total Cost: $35 million
Opened: September 1, 1999
Source

If I've left any off the list, please let me know! I've been piecing together the info from a bunch of different sources so it's always a possibility.