Seven and a half is for 3000 meters. HOWEVER, since the water jump is placed either inside or outside the second bend, this alters the exact number of "laps" run (7.5). The most common place to find a water jump is on the inside of the second bend, which would make the laps smaller. Hence you would start the race 35 metres back from the 3,000m start point. Hence the answer is "just over" seven and a half laps.
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