My recommendation would be that humans put that same mental energy currently being used to plot how to bring icebergs to hot climates towards how to conserve water and ensure we have enough for truly important things. It is a finite resource and we don't always use it intelligently. Whether it's farmers using cheap water to grow crops in areas the plants aren't really suited to, or cities draining rivers to support large populations in dry areas, or (a personal pet peeve of mine) people dumping gallons of water onto lawns to keep them green in the peak of summer, it's clear we don't have our priorities straight. So many people on this planet still don't have clean water to drink and yet the world's wealthy have all the water they require, for whatever frivolous purpose they desire.
Take India for example. Many Indians don't have access to the water they need - not because India doesn't have enough water, but because it's not well managed. And in many places in the U.S., despite the widespread availability of safe tap water, people insist on buying bottled water, which requires water for its production! In many cases, we already know of strategies that can reduce waste, and policies that encourage responsible water use. With sufficient political will, we can invest in infrastructure to deliver safe water to the poor and eliminate incentives for the well-off to use as much water as they like. We don't need to waste time dragging icebergs around the ocean.