JOEL - As Joseph Smith and his associates returned to Kirtland after visiting Missouri they experienced problems on the Missouri River. On Aug. 13, 1831 the Prophet recorded,

"many of the dangers so common upon the western waters manifested themselves and after we had encamped upon the bank of the river, at McIlwaine's Bend, Brother William W.T Phelps, in open vision by daylight, saw the destroyer in his most horrible power, ride upon the face of the waters; others heard the noise, but saw not the vision," . (History of the Church 1:202-3.) Later, the group was warned in a revelation that the adversary has some control over the elements as recorded in the D&C.:

4 Nevertheless, I suffered it that ye might bear record; behold, there are many dangers upon the waters, and more especially hereafter;
5 For I, the Lord, have decreed in mine anger many destructions upon the waters; yea, and especially upon these waters.
14 Behold, I, the Lord, in the beginning blessed the waters; but in the last days, by the mouth of my servant John, I cursed the waters.
15 Wherefore, the days will come that no flesh shall be safe upon the waters.
16 And it shall be said in days to come that none is able to go up to the land of Zion upon the waters, but he that is upright in heart. (D&C 61:4-5, 14-16)

Here is the scripture where John talks about the cursed waters:
8 And the second angel sounded, and as it were a great mountain burning with fire was cast into the sea: and the third part of the sea became ablood;
9 And the third part of the creatures which were in the sea, and had life, died; and the third part of the ships were destroyed.
10 And the third angel sounded, and there fell a great star from heaven, burning as it were a lamp, and it fell upon the third part of the rivers, and upon the fountains of waters;
11 And the name of the star is called Wormwood: and the third part of the waters became wormwood; and many men died of the waters, because they were made bitter. (Rev 8: 8-11)

The prophecy in these scriptures was considered to have been fulfilled on the Missouri and Mississippi rivers during Joseph Smith's day and later during world Wars I and II, with all the death and destruction that happened on the seas. It can also refer to floods, hurricanes, and contamination of the water happening in our day. The Wormwood mentioned in the Revelation scriptures, is a plant symbolic of bitterness, calamity, and sorrow. The introduction of wormwood into the waters would make them undrinkable, or at the very least bitter and distasteful. Atomic fallout could account for making a third of the water of the world undrinkable.
Regardless of the interpretation of these scriptures, ever since this revelation, missionaries have been advised to stay away from the waters as much as possible. But it's really more of a safety thing rathar than any unusual control Satan might have over them just because they are on the water. As the scripture said, "he that is upright in heart"(D&C 61:16) should not be affected by this curse.

Link to Scripture