Paragraph 37 I1

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 river as may be necessary during or in consequence of the construction of a tidal work;

provide and maintain on any tidal works such fog signalling apparatus as may be reasonably required by the Port Authority and shall properly operate such apparatus during periods of restricted visibility for the purpose of warning vessels of the existence of the relevant works; and

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.