The first section of the Matrimandir test lake nears completion

Yet, five metres is only half of the lake’s projected depth. “We have installed 1,200 blocks to the five metres level, we need about 2,500 blocks more to bring both walls up to 10 metres,” says Jan. “We are making 16 blocks a day, so in another 200 days we will have a sufficient number of blocks to go all the way up.” The blocks, each weighing 2 tonnes, are made on site.

The walls are tapering upwards, from 4,5 metres at the bottom to 75 centimeters at the top. “The walls need to withstand the hydraulic pressure,” explains Jan. “The pressure at the bottom of the 10 metres deep lake will be 10 tonnes per square metre if the lake is full. The sheer weight of the wall will prevent that the pressure pushes it away. When we heighten the walls by spring next year, we will thicken them with another 1,5 metres.” It is expected that it will take three years for the lake to fully fill up during a normal monsoon. Excess rainwater will be directed into a canyon, from where it will flow into the Irumbai Lake. In the summer, the water level will go down due to evaporation; but for the time being no other sources than rainwater will be used to fill up the lake and maintain the level.

The cost of this project is immense. It is thanks to Michael Bonke’s drive and commitment that building the Matrimandir lake has started. He put together the technical team that provided the concept and design and oversaw the execution; he provided a major part of the funds to purchase some of the heavy machinery, and sent the hdpe liner and geotextile from Germany, and paid for the German expert to do the welding of the hydrofoil. And it was through his efforts that the Matrimandir received substantial donations for making the lake.

If the test lake functions as expected, the next section of the lake will start. “We are still discussing in how many sections we will make the lake,” says Jan. “Originally we were thinking of sections of 100 metres long, but it should be feasible and less expensive to continue now with sections of 275 metres each.” The next section will be dug next to the test lake wall. At its far end a third 10-metres high wall, for which another 2,500 lego blocks will be needed, will be erected. When the flooring and sides of the new section have been done, the wall separating it from the test lake will be removed. The removed blocks will be used again for the next section.

One question remains: what to do with all the earth from the excavation. “There is an idea to build a large hill with it in the Greenbelt, with a lake on top,” says Jan. “But that still needs to be studied. Another suggestion is to use part of it for the visitors’ hill, as suggested by The Mother, from where day-visitors can see the Matrimandir and the gardens. In the meantime, we’re dumping all the excavated earth on a hill near the Matrimandir.”