Because the Bible was written in a part of the world where water is scarce it is not surprising that water features significantly in the lives of the people. The scarceness of water was very serious and drought was often as a result of the wrath of God. The prophets Elijah, Jeremiah and Haggai all predict drought as punishment from God (1 Kings 17:1, Jeremiah 14: 1-6 and Haggai 1: 10-11 respectively). Conversely rainfall is a sign of God's favour and goodness.
Water was often associated with danger and death, as in the story of the Great Flood, the drowning of the Egyptians in the Red Sea and the fear of the sea and deep waters expressed by the Psalmists as in Psalm 32:6
For this shall every one that is godly pray unto thee in a time when thou mayest be found: surely in the floods of great waters they shall not come nigh unto him.
Polluted and undrinkable water was also very serious. One of the plagues of Egypt was turning the waters of the Nile river to blood (Exodus 7:14-24). When the Israelites left the Red Sea and came to Marah they found the water there bitter and complained to Moses. God allowed Moses to perform the miracle of making the water sweet and restored the Israelites faith in Him (Exodus 15:22-27).
In warfare it was common practice to cut off a city's water supply as Jehosaphat did with the wells of Moab (2 Kings 3:19-25).
Water was also important for cleansing. Priests were washed at their consecration (Exodus 29:4), special ablutions were demanded for priests on the Day of Atonement (Leviticus 16:4, 24, 26) and of all men for the removal of ceremonial pollution (Leviticus 11:40, 15:15, Deuteronomy 23:11 etc).
Water is also symbolic of God's blessing and spiritual refreshment and is used many times in the Bible. The following are just a few examples:
..for in the wilderness shall waters break out, and streams in the desert.
And the parched ground shall become a pool, and the thirsty land springs of water..
When the poor and needy seek water, and there is none, and their tongue faileth for thirst, I the LORD will hear them, I the God of Israel will not forsake them.
I will open rivers in high places, and fountains in the midst of the valleys: I will make the wilderness a pool of water, and the dry land springs of water.
The longing for water indicates spiritual need as in Psalm 42:1-
As the hart panteth after the water brooks, so panteth my soul after thee, O God.
In Ezekial's vision of God's house the waters that poured from under the threshold represent the unrestricted flow of God's blessings upon his people (Ezekiel 47:1-12).
Jeremiah describes God as " the fountain of living waters" (Jeremiah 2:13, 17:13).
In the New Testament water is connected with the gift of eternal life. Some examples are
But whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall be in him a well of water springing up into everlasting life.
...I am Alpha and Omega, the beginning and the end. I will give unto him that is athirst of the fountain of the water of life freely.
See Living Water
Water is also connected with the baptismal cleansing for the forgiveness of sins as in Hebrews 10:22-
Let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience, and our bodies washed with pure water.