Paragraph 4

The Council shall pay to the Port Authority the reasonable costs incurred by the Port Authority of such alterations to the marking and lighting of the navigational channel of the Ouseburn as may be necessary during or in consequence of the construction of a tidal work.

The Council shall afford to the Port Authority such facilities as they may reasonably require for the placing and maintenance on any tidal works of signals, tide-boards, tide-gauges or other apparatus for the safety or benefit of navigation.