How to build a sewage treatment plant in an afternoon. Reservoirs.

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  First you find a nice site. Then you get some boys with their toys to turn it all upside down.
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  And do they like it. Well enough to take 5 m toplayer and drive it off in trucks. Then they brought some new nice sand and spread all over the site.
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  Then they leveled it all out and started to make some circles in the sand.
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  On top of the sand they cast some concrete which started to look like the bottom plate for 4 reservoirs. Two large aereation tanks and 2 smaller settlings tanks.
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  To make the surface smooth they were using helicopters. I loved the "chinook", 2 propellers and a seat in the middle.
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  To make things a bit complicated then the hydrolyse tank is inside the aereation tank.
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  Here you see the 2 center tanks.
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  All walls are made of pre-cast elements tied together with PEH covered steel wire. All panels are aligned with a laser. Seals are made between the elements and the bottom. A very quick and high quality solution.
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  Service bridges for the 2aereation tanks. It looks like the boys got it right.
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  Meanwhile a center bearing has been installed in he settling tank. Here you can see the scraper bridge incl. boogie ready to lift into position.
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  Bottom scraper is pulled behind the rotating scraper bridge. At water level a scum scraper is installed to guide the scum to the scum outlet. Welders have assembled the drain canal wery nicely. +- 2mm. on the level
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  The finished settling reservoir looks good. Bridge is fully hot dipped galvanised and all other installations made of high class stainless steel.
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  A ring pipe for aereation air is put up along rim of the reservoir. Soil is now being filled round the reservoirs. And the levelling of the site starts to take shape.
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  Air comes from a row of large blowers installed in the preteratment building. Our welding contractor gave his staff a opportunity for some fittness exercise during working hour.
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  These welders were fit in many ways. The pretreatment building is seen in the background.
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  Back to the reservoir. Here is the entire aereation system, unpacked and ready to assemble.
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  Supports for the airharps are drilled into the bottom plate. All supports are aligned in height with laser. Admittedly then it took the team a bit of time in the first reservoir. At the 5 th reservoir we only used a tenth of the time.
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  All air harps are installed and connected to the ring pipe via the droplegs. 900 dustbin bags has been used for protecting the rubber membranes against UV rays from the sun.
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  Then fit in a couple of mixers in each reservoir, add a bit of sewage and it is time for testing the airharps and membranes.
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  Round bubbles, round menbranes and squared pattern on the surface. Havent figured out how but it looks facinating.
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  Time to fill the reservoir and start the aereation system. Some foam is allways formed at first start. Sergey seems to wonder if he used too much soap during his morning shower.
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  See, it was just a walk in the park, but now its time for a short rest.