Sforno on Genesis 1:9/ספורנו על בראשית א׳:ט׳

1יקוו המים; this does not mean that the waters should dry up, as many people interpreted it. These people said that the process would be achieved by a substantial part of the oceans freezing and turning to ice such as the polar regions, and that this would be caused by forces in the celestial regions. אל מקום אחד. The waters should not deviate from this location. As a result they became much higher than the surrounding land mass without crashing down on earth as our senses would have us think would be the case. This is why David tells us in Psalms 104,9: גבול שמת בל יעברון, “You have set them limits which they must not cross.” The meaning is that the waters must not flood the earth.”