Lower Water

This spell causes water or similar liquid to reduce its depth by as much as 2 feet per caster level (to a minimum depth of 1 inch). The water is lowered within a more or less square-shaped depression whose sides are up to 10 feet long per caster level. In extremely large and deep bodies of water, such as a deep ocean, the spell creates a whirlpool that sweeps ships and similar craft downward, putting them at risk and rendering them unable to leave by normal movement for the duration of the spell. When cast on water elementals and other water-based creatures, this spell acts as a slow spell (the reverse of haste); a save vs. Spells is allowed, with success negating the effect. The spell has no effect on other creatures.