These ponds were designed as mirrors for reflections of their building designs I gathered. Some fangled idea from an architect.
Obviously they collect the rain water, the runoffs and erosion,they are too shallow to be natural ponds, nature is claiming them. So I suggest they should add 6-8 inches of top soil, plant them permanently with wetland plants, hire a landscape architect that knows aquatic and wetland plants to draw a plan that emulates a natural wetland.
No more chemicals, no more spending of budget in a chemical soup trying to make nature's wet bowl look like a mirror.
Instead, water purified as it runs away from human's presence. A mini wildlife refuge (kids wont wade in the swamp much!) The sediments are going to keep feeding the beautiful indigenous plant species, newts and frogs will appear, then a reclaimed habitat, a chance to start new and fresh!
Long term investment instead of short term spending... my two cents!