Approximating the Sinusoidal nature of Tidal flows			Example for a 6m tide
1st hour		1/12 of the tidal range	0.5 m
2nd hour	a further	2/12 of the tidal range	1.0 m
3rd hour	a further	3/12 of the tidal range	1.5 m
4th hour	a further	3/12 of the tidal range	1.5 m
5th hour	a further	2/12 of the tidal range	1.0 m
6th hour	a final	1/12 of the tidal range	0.5 m

Half the total amount of water flows during the middle 2 hours of the 6-hour long tidal stream.