...why don't you just fill the ponds to a decent depth? You don't need a 2+m depth pond to grow lotus or have koi carps: less than 1m is OK for both... Koi are pretty resilient and they will be alive even if the surface of the water freezes and lotus will grow better when they're not buried THAT deep in the ground........ I do really wonder why they made those ponds so deep that people could drown in them... Or was that why they made them that deep?
And this chapter just made me think about that curse where you put a lot of insects in a jar, seal it and leave it alone until just one insect is left...