Corrugated Steel Cisterns
Above Ground, Corrugated Steel
Benefits of Above-Ground Tanks
- Cost – Above ground tanks cost approximately 40% less than below ground tanks. Especially in areas of Georgia with rocky soil or high water table, above ground tanks are worth extra consideration. Cost savings are due to:
- Reduced Shipping Costs
- Reduced Material Handling Costs – carried by hand or skid-steer on the jobsite, not a crane.
- Reduced Sitework – pouring a concrete foundation vs. excavating.
- Maintenance – With a properly functioning prefilter, neither tank requires much maintenance. Maybe every few years. In the past, both above and below ground tanks required confined space safety procedures. However, access hatches allowing egress through the liners are the next technological breakthrough for these tanks.
- Pumping – With positive suction pressure, pumps run smoother and more efficiently. Pumps can be located inside a mechanical room, safe from the environment and eliminating the need to run high voltage electricity outdoors.
- We should not neglect the publicity aspect of above-ground tanks. Those that want to spend the extra money on green initiatives often want their neighbors to know. For businesses, it’s good business to subtly let your customers know that you care about the earth.
- Steel tanks have a certain look, that matches the design of many modern buildings. For buildings with a brick or stone veneer, that look can be extended to the tank.
Challenges of Above-Ground Tanks
- Freeze Protection – The biggest challenge with freeze protection is not the tank itself, but any piping with sitting water. The current generation of tanks solved that problem for the most part, with piping penetrations inside the tank. The mass of water in the tank will freeze on the surface, but it will not damage the tank. Freeze protection in Georgia can be accomplished with smart recirculation, keeping initial costs low.
- Aesthetics – The Great Debate among engineers: are the tanks something to hide or something to show?. With a tank such as this in full view of passersby and customers, people will certainly know that the business owner is collecting rainwater. As described in this Freakanomics article, that might be very desirable indeed. By far the most common visual option is unpainted galvanized steel. Epoxy coating and urethane mastic is available. For a different look, the exterior can be clad in wooden planks to simulate staves, or stone or brick.
- Space – The best tactic for maximizing space is to size the tank for the usage, not expected rainfall. This also reduces the cost of the project.
Corrugated Steel Tank Options
People use these tanks in buildings as diverse as remote ranch houses, to commercial and industrial sites in earthquake and hurricane-prone locations. Applicable codes and standards could be AWWA D103 for municipal water supply, NFPA-22 for fire protection, NSF 61 for protection of drinking water, or none at all. So it shouldn’t be surprising that prices for the same capacity can vary by 50% or more. We have prepared the guide below to help you decide which price point is right for your project:
Gold | Silver | Bronze | Lite | |
|---|---|---|---|---|
Structural Components Material | Steel | Steel | Steel | Aluminum |
Max Snow Rating (5 PSF is max required in Georgia) | 50 PSF | 50 PSF | 50 PSF | 5 PSF |
Access Hatch in Wall (not just a bolted wall sheet) | ||||
Powder Coat Option – Multiple Colors | ||||
Roof Platform | ||||
Walkaround Stairs | ||||
30°, 10°, and Flat Roof Options | ||||
Site Specific Structural Calculations: seismic, wind, snow | Optional | |||
Flange Connections | Steel | Steel | PVC | HDPE |
Floor Penetration Option – Freeze & Tamper Resistant |
Texas Metal Tanks
Georgia Water Tanks keeps an inventory of Texas Metal Tanks, 300 – 500 gallon sizes. Texas Metal Tanks manufactures both traditional galvanized steel cisterns and stainless steel cisterns. The galvanized steel tanks are G-90 grade 20 gauge metal made in the USA. We do not import foreign steel. The top is 22 gauge. After the tank is constructed, a paint / epoxy lining is applied to the interior of the tank to provide a protective barrier between the water and the metal itself. This product is FDA approved for potable (drinking) water applications and is ANSI / NSF 61 certified. Each tank is tested at the factory to ensure that it is watertight. With almost 90 years of history, these tanks have a typical lifespan of 30 – 35 years. Galvanized tanks have a one-year warranty.
CURRENT INVENTORY
Capacity | 300 Gallon | 400 Gallon |
|---|---|---|
Diameter | 36″ | 42″ |
Eave Height | 5′ 8″ | 5′ 8″ |
Drain Outlet | 3/4″ | 3/4″ |
Inlet Fitting | 4″ | 4″ |
Price (FOB Doraville) | $1400 | $1650 |