sentences:  During the change of tides this causes the water to flow at a rate of up to 7 knots (13 km/h).A set of rocks further constricts the water, especially during higher tides, and this causes hydraulics to form in the shape of glassy standing waves and broken waves (also known as stoppers).Numerous guidebooks detail the route to The Bitches, but it is not for the inexperienced or unprepared.