SIGNAL TOWERS

Routing trains safely, flexibly and efficiently depends on signal towers, sometimes called block stations, signal stations or interlocking towers. When opened the new Union Station had more than a dozen tracks and a high density of traffic that had to be expeditiously directed to the appropriate track without error or accident. To provide for a maximum of flexibility a large number of track switches were arranged so that incoming and departing trains could be routed to any one of the several tracks. The signal towers also had to accomodate light engine movements, switching moves, freight trains and trains moving to storage yards. For safety switches and signals were "interlocked" in a way that would prevent a tower man from setting a route that would place trains on a collision course. The three towers that directed trains at the Union Station were from west to east Brayton Avenue, Promenade Street and Orms Street which were also known on the New Haven as, respectively, SS149, SS151 and SS152. There was also Gaspee Street, SS150, which was not actually a tower but simply a cabin with a switch tender who operated certain switches manually.

The SHORELINER, a publication of the New Haven Railroad Historical & Technical Association, included a detailed article on the Providence Signal Towers by Peter E. Lynch in Volume 17, Issue 4, 1986.

Orms Street Tower as seen from the Orms Street bridge when the tower was opened in 1892. The tower was recessed because of the narrow cut through Smith's Hill. The Charles Street Roundhouse and coach yard and the Oregon Street Roundhouse are to the left beyond the Chalkstone Avenue bridge. It can be seen that the switches at this point allowed movement from any one track to any other track in both directions.

An I-4 Pacific leaving Union Station as seen from the Orms Street Tower. The Orms Street bridge is in the background.

Brayton Avenue Tower (right) was built to control the west end of the new Union Station.

An I-5 Hudson built by Baldwin in 1937 passes SS 149, the Brayton Avenue Tower, while entering Union Station from the west. The arrangement of double slip switches is similar to that at Orms Street.

The original Promenade Street Tower (left) was built to control the east approach to the new Union Station but it was used as signal tower for less than ten years because the junction created by the tunnel required a new Promenade Street tower. The double slip switch is one of many that were located on both sides of the Union Station. The photo was taken November 17, 1939.

The new Promenade Street tower is at the junction of the tunnel line and main line (bottom center) while the old Promenade Street tower is right center next to Tefft's Boston & Providence freight station. The Post Office is at the bottom of the photo. It had direct access to mail car sidings on the tunnel viaduct.

SS 151, the new Promenade Street tower which replaced the original SS 151 when the tunnel was built. This concrete tower assumed the duties of Orms Street in 1943 and Brayton Avenue in 1946.

The diagram shows the complexity of the track layout at Promenade Street

The interior of SS 151 at Promenade Street. The electric interlocking machine was installed in 1943 to replace a 77 lever interlocking machine that used large levers to control electric switch machines. The new machine also replaced the 40 lever interlocking machine at Orms Street that used levers that moved rods that reached each switch.and mechanically changed its position. The electric switches on the illuminated track diagram control track switches. The panel below has switches to control signals.

THE PROMENADE STREET TOWER WAS DESCRIBED IN AN

ARTICLE ON PAGE 4 OF THE DECEMBER 1943 ISSUE OF ALONG THE LINE

The November 17, 1939 view from across the tracks from the old Promenade Street Tower. Smith Street is in the background. The series of double slip switches, one seen here, were removed in 1943 and replaced with easier to maintain crossovers.

View from Smith Street. The old Promenade Street Tower is in the center, the Boston & Providence freight house is on the left as is the siding that served meat dealers; notice the Wilson & Co. sign. The old team yard is on the right. The train led by an ALCO DL-109 is heading for Boston while the ALCO diesel switches some passenger cars.

AN APRIL 1969 VIEW FROM SMITH STREET LOOKING NORTH TOWARD ORMS STREET

AND THE LOCATION OF THE LONG GONE SS 152.

The Smith Street hill posed a difficult obstacle for the early railroad builders who had to cut through high ground.

VIEW FROM ORMS STREET - EARLY 1950's

The Smith Street bridge is in the distance. The locomotives are the Alco DL-109's that were the New Haven's first diesels to be used in road service, hauling both freight and passenger trains.