Cloak of the Sea

The subject retains his or her form but takes on a blue-green watery appearance.

(Complete Adventurer)
Orginally posted on D&Dtools

Transmutation
Level: Druid 5, Sorcerer, Wizard 6,
Components: V, S, DF,
Casting Time: 1 standard action
Range: Touch
Target: Creature touched
Duration: 1 hour/level (D)
Saving Throw: Will negates (harmless)
Spell Resistance: Yes (harmless)

While underwater, the subject functions as if affected by blur, freedom of movement, and water breathing and doesn’t take nonlethal damage from water pressure or hypothermia for the duration of the spell.

When out of the water (or even partially out), the subject gains none of these advantages except water breathing.

The subject can leave and reenter water without ending the spell.