For as long as humanity has relied on water storage tanks to help sustain communities, we have also sought out to improve on them in bigger and more efficient ways. As of 2016, the best means of water storage are precast and prestressed water tanks, which prove much more beneficial than standard water tanks in multiple ways.

About Precast Tanks

Precast water tanks are tanks that were initially formed by use of a cast, then allowed to age in a stable facility. These tanks prove to be extremely reliable based on the fact that they’ve been used for centuries, and date as far back as the Roman period. During that time, the Romans used precast tanks to power their entire plumbing system. Some of the old Roman precast tanks can still be found in modern day Rome, perfectly intact and, in some cases, completely functional.

As evidenced by the Roman tanks, precast water tanks are incredibly durable. This trait allows them to stay intact for many years. They are the least likely to fracture over time, which means your community’s water will remain safe under almost any circumstance—especially earthquakes, which commonly do the most damage to water storage systems. Their manner of construction also allows manufacturers to create them faster.

Standards for Precast Tanks

The American Concrete Institute (ACI) publishes standards for all concrete tanks. These standards allow builders to manufacture tanks that will last stand up to environmental elements such as earthquakes. When it comes to precast tanks, preserving the concrete and other materials is key. Small flaws—namely, superficial damage—are passable, but any breakage that seeps past the tank’s surface is par for rejection. The placement of concrete must be as precise as possible in order to ensure its solidity. It must be at least 4,000 psi in compressive strength. The water poured inside of precast water tanks mustn’t include any elements that could damage the tank’s composite materials.

About Prestressed Tanks

Prestressed concrete tanks emerged during the 1930s as a solution to the more fragile cast-in-place tanks in use before. Prestressed tanks are made from mixing concrete with sturdy metal components, including a shell made from steel. This lends the tank ample support and makes it much more long lasting. In fact, the tank’s use of wire and shotcrete help to prevent corrosion, which can destroy a tank over time and make it less effective. The metallic shell helps ensure a water tight design and inhibit the possibility of leakage. Just like precast tanks, they are secure in the face of earthquake-related disasters.

The average prestressed concrete tanks can hold anywhere between 50,000 and 20,000,000 gallons of water at a time, making them efficient functionally and economically.

Standards for Prestressed Tanks

Prestressed tanks require a certain level of safety and efficiency set by the ACI. They must be able to hold at least one million gallons of water. For drainage purposes, the tank’s bottom half must slump downwards. Plumbing extending from the tank to the underground must be outfitted with durable enforced concrete. Walls are generally made from shotcrete and given support by multiple steel bearings, usually layered together.

For more information on the construction and benefits of these two types of tanks, contact us. It’s our goal to spread environmentally and economically conscious construction across communities.