Reliable underground plastic clean-water tank - drinking water-approved solution
Kemic Vandrens
New water plant - From worn concrete tanks to new plastic clean-water tanks
The existing tanks at the waterworks were all made of concrete, but from previous experience, the board preferred not to use it as the material for new clean-water tanks.
The board discussed many different solutions, before finally deciding to expand the waterworks, merging the whole supply and decommissioning the old concrete tanks.
The expansion of the plant required new clean-water tanks, and a future-proof solution was sought that would comply with stricter requirements for storing clean water. Therefore concrete was out of the picture and an alternative to steel tanks was needed.
A safe alternative to steel
Finding an alternative to steel tanks was important, as the total project cost had to be kept down in order to avoid price increases for consumers.
The solution of using plastic tanks buried in the ground offered dramatic reductions in costs for a waterworks building, as it obviated the necessity of housing large steel tanks indoors. It also promised lower future operational costs, and the board was satisfied that water would be stored safely.
“I went to see another waterworks. They had chosen a high-chrome solution, all in stainless steel, and it cost upwards of 25 million. In my opinion, I got more or less the same for a third of the price, with water stored in safe, approved solutions”
Drinking water-approved and future-proof solution
“I have seen pictures from other waterworks where the tanks have been in a grim state. With large cracks and holes in the tank, where various creepy-crawlies found their way in,” says operations manager Arne Schmidt.
The waterworks therefore wanted a drinking water-approved alternative to steel that could be made in custom dimensions so that the waterworks could tailor it to their requirements. It was also important to operations manager Arne Schmidt that the tanks could be accessed from a clean environment and that there was scope for draining the water. He also wanted high reliability and minimal maintenance for his new tanks.
Solution with a hygiene and safety focus
We delivered three new clean-water tanks made of solid, durable PE plastic with a total water capacity of 650 m3.
We distributed the capacity over three tanks to increase the security of the water supply. A “snitch” sensor was also installed to notify Arne Schmidt of any leaks. It should be said, however, that outside water will never be able to reach the clean water, as the tank is double-walled.
The new tanks were buried and arranged so that the end of each tank is accessible from a clean cellar, so enhancing hygiene. Burying the tanks also increases water safety, as the surrounding soil helps to keep the water temperature down. A drain was also placed under each of the three tanks to prevent standing water from accumulating around the tanks.
“I now have a really good solution for our drinking water storage. Everything has come together well. The small issues we’ve had are now solved, and everything I was keen to see happen has happened.”
Arne Schmidt, Operations Manager