3 ponds in 170 acres doesn't sound like any diversion to note. This is about .gov owning and controlling your land - and making you pay for the privilege.
First of all, it doesn't say how big those 3 ponds are. By definition, a "pond" can be any body of water up to 19 acres (actually 8 hectares to be exact), regardless of depth. 3 "ponds" can be a lot of water.
Secondly, the issue isn't him having the retention ponds to collect rainwater. The issue is that this guy thinks he can divert a tributary of a decent sized river that supplies water for a town to fill his ponds. Not only that, but he was fined for it before, he knew it was wrong, and he still continues to do it.
Yeah, one person diverting a stream for their personal ponds probably doesn't make a whole lot of difference, but if this guy can do it, why can't his neighbor and his neighbor's neighbor and so on. If that happens, civilization is beholden to the few who "own" the water supply.