Inaccurate?

Dark Tide

(Stormwrack)

Necromancy [Evil, Water]
Level: Blackwater 7,
Components: V, S, DF,
Casting Time: 1 full round
Range: Long (400 ft. + 40 ft./level)
Area: One-half mile radius spread
Duration: 1 hour/level (D)
Saving Throw: Fortitude half
Spell Resistance: Yes

You infuse the target area with the enervating essence of the blackwater depths, creating a tide of blackwater that spreads out from the designated point of origin at a rate of 100 feet per round until it fills the entire area.
The water is black and terribly chilling, and its touch causes a sense of fear in those affected by it.
Those within the area must make a Fortitude save when they first enter the blackwater (or when it first surrounds
them).
Failure indicates that they take 1 point of Strength damage.
Additionally, every creature in the area takes 1d6 points of negative energy damage for every hour they remain in the dark, murky waters (no save).
Spells that protect against negative energy damage will prevent the Strength damage.
Creatures who take damage from the dark tide are considered shaken as long as they remain in the area.
This spell is a favored first move by sahuagin and other blackwater-dwelling creatures before they attack the settlements of their enemies.