To improve its competitive position, reservoir manufacturer Rainbow Reservoirs has started manufacturing several reservoir component parts locally and plans to soon start rolling the Zincalume steel panels that are used to construct the reservoir walls.

The panels are currently cut from flat sheet Zincalume and rolled at the overseas factory to give the panels the correct profile and curvature. When the panels are packed into containers for shipping, both the profile and the curvature take up container space.

Local rolling will increase the number of flat panels that can be packed by the source factory overseas into a shipping container, thus lowering shipping costs and helping Rainbow Reservoirs keep its prices down.

Panel cutting and punching are likely to continue being done abroad because of the precise nature of these operations and the high cost of the required machinery.

Rainbow Reservoirs MD Wayne Thompson says a global shortage of freshwater continues to drive reservoir construction. Freshwater comprises just 3% of all water covering the earth’s surface, and much of it occurs only in the form of unusable ice.

He adds that, in recent years, steel panel reservoirs have been adopted by commerce, industry and the construction sector because of their increased structural sophistication, as well as the space savings and ease of installation they provide.

However, Thompson states that the agri- culture sector has largely ignored this convenience, preferring brick and mortar struc- tures, which have, over time, become ingrained as the generally accepted method of construction.

“In some sectors, the steel alternative remains incorrectly viewed as expensive. The purchase price is possibly, generally, higher than a brick and mortar alternative, but when viewed in terms of overall lifetime costs, the panel reservoir is cheaper,” he says, pointing out that the lower lifetime cost is the direct result of the longer effective life span of the steel panel reservoir.

Thompson says Rainbow Reservoirs’ product offers leak- and corrosion-free operation for more than 30 years, while brick and mortar reservoirs, by contrast, have an effective life span of around 15 years.

He believes the inherent strength of the steel reservoir is often misunderstood.

He argues that cracks and bursts that routinely occur in brick and mortar reservoirs, as a result of unsound construction and earth movement, should cast doubt on a preference for older methods of reservoir construction.

“Although steel remains expensive, the price of cement recently saw a dramatic rise, reducing the advantage of a lower initial outlay for a brick and mortar reservoir.

“When the projected life span of such a structure is compared to the life of the steel reservoir, the case for the latter becomes clear,” he states.

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