Large water storage tanks are used for commercial, agricultural and home purposes. In areas prone to drought, or for preparedness purposes, having access to extra water is important and sometimes essential. For those dependent on municipal water sources, having a secondary supply for backup is a prudent idea. Those on wells may want a aboveground water storage tank for times when electricity is out.
Shop online to get an idea of what types of large water storage tanks are available, as well as the cost. You may be able to find a 300-gallon poly tank for as little as $200. Look for a supplier near you to save on shipping. If you can pick it up yourself, you'll save considerably.
Decide which type and size of water tank you need. Also consider where it will be placed, how you'll fill it, and what structure will house it. These logistics will likely influence your decision. If you have garage space and can fill the tank with a hose, you might want to pick a tank that can easily fit in your garage space.
Check local ads, online and in print, for water barrels. Many 55-gallon water drums can often be purchased for under $15 each.