(1)The railway undertaking may—
(a)construct a new railway;
(b)carry out any work for the improvement of an existing railway,
where it appears to the railway undertaking expedient to do so for the purpose of providing railway services.
(2)The Department may, on application to it by the railway undertaking, make an order authorising the railway undertaking to construct, as part of a new railway or as part of an existing railway—
(a)a bridge over any navigable waters specified in the order (whether sea, river or other navigable waters); or
(b)a tunnel under any such waters.
(3)An order under subsection (2)—
(a)shall include such information as may be necessary to indicate the position and minimum dimensions of the bridge or tunnel, (including, for a bridge, its minimum spans, headways and waterways and, for a tunnel, its minimum depth below the bed of the navigable waters); and
(b)shall, if it relates to the construction of a swing bridge, contain such provisions as the Department considers expedient for regulating the operation of the bridge.
(4)Before making an order under subsection (2) the Department shall take into consideration the reasonable requirements of navigation over the waters affected by the order.
(5)In this section —
“improvement” includes (without prejudice to the generality of that expression) the widening, realigning and reshaping of a railway;
“navigable waters” means waters over which a public right of navigation exists;
“swing bridge” includes a bridge which opens by any mechanical means.]