In the first higher temple of this dispensation, Nauvoo, had a spring in its basement precisely for filling the font naturally - without having to haul water from the well that was on the lot. There is a reason that there were aquaducts that brought fresh water into the city - partly for the reasons above and partly for a protection against a siege - a military tactic.
It only makes sense that water has a memory - as it is present at nearly every major event in our lives. From our birth, to our baptism, to our taking of the sacrament, to washings and anointings in the Temples, to so much else. Our body consists of over 3/4 water - through blood and other fluids.
Here is a great scripture that brings it all into perspective:
5 Who is he that overcometh the world, but he that believeth that Jesus is the Son of God?
6 This is he that came by water and blood, even Jesus Christ; not by water only, but by water and blood. And it is the Spirit that beareth witness, because the Spirit is truth.
7 For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.
8 And there are three that bear witness in earth, the Spirit, and the water, and the blood: and these three agree in one.
Water is an amazing thing:
The new temple films are fantastic, in that they depict things as they are - and as they will be. Water came out of the middle of the Garden of Eden and flowed fours ways as the head of the rivers Gihon, Euphrates, Hiddekel and Pison:
10 And a river went out of Eden to water the garden; and from thence it was parted, and became into four heads.
11 The name of the first is Pison: that is it which compasseth the whole land of Havilah, where there is gold;
13 And the name of the second river is Gihon: the same is it that compasseth the whole land of Ethiopia.
14 And the name of the third river is Hiddekel: that is it which goeth toward the east of Assyria. And the fourth river is Euphrates.
This is exactly what will flow out from the New Jerusalem - and the living water will go forth and heal the land and will have amazing results - according to Spencer. The fruits will not spoil, they will be large and will be true medicine for those who ingest them.
In the Old Jerusalem - the same thing will occur shortly; living water will come out from under the Temple there and it will flow down and will heal the Dead Sea of it's maladies. This is both symbolic and literal.
I have to end here with a thought relating to the NJ and the OJ and the Nauvoo Temple and the Zarahemla Temple - as book ends on God's work. Eventually, the Mississippi will be quite wide at that location. I expect a temple again in Zarahemla - and the two will bookend that place, just as the two Jerusalems will bookend each other. There is symmetry in this. In the old land, we have the river Jordan flowing south into a dead sea. In the new land, we have a river Jordan flowing north into a dead sea. As you look at things in a clock-wise manner, the temple is located in the center of these two things. I would love to see what is at the mid-point of those two places.