The point is to get rid of the wastewater safe/cheap/efficient rather than grow the forest. Water consumption isn't the concern. They certainly wouldn't be doing drip irrigation with wastewater because wastewater would clog the equipment. Evaporation is expected and desired. Treated human waste is full of pharmaceuticals and phosphates from detergents. It should not be used to grow food unless it is feed for animals. Drainage is a concern on sandy soil. You wouldn't want these sites anywhere near your groundwater supply. You can't dump phosphates and nitrogen in your rivers because the result is algal blooms -> depleted oxygen -> fish kills and really toxic shit like Pfiesteria, which can give you headaches, cognitive problems, and nerve damage just from standing knee deep in the water.
Really, how well the forest grows is beside the point. They're doing this to dispose waste water. If they can make a tree crop to offset costs a bit, then great. The "climate change" angle is lipstick on the pig.
> It should not be used to grow food unless it is feed for animals
If the potential toxins on the crop are the concern, these animals can also then not be for human consumption (directly or indirectly). In a lot of cases they probably can't even produce things for human consumption. There's not a whole lot of use left once you eliminate those use cases.
It depends on what is in your wastewater of course, but most toxin typically concentrates in the leaves rather than the beans/corn. From there, the toxin remaining concentrates mostly in organs which can be discarded, rather than the meat. Each step in the food chain acts as a filter. You do not want to consume the crop directly and have buildup in your organs.
Also, eating food irrigated with waste sludge is a great way to catch e-coli. Treated waste is aerated and anaerobic pathogens like that largely neutralized, but it could still happen. If a hog is sick/dies, it's not as big a deal as a human.
Steps in the food chain are concentrators for toxins, not filters. Discarding organ meat isn't a given, though I suppose throwing away the liver in a lot of cases would be a solution. It seems like it is a risky play for relatively little gain, but I'm not a food regulator.
It would certainly help if you explained why you feel the need to snark about something you can't really know about. That way the comment might serve as a vehicle for interesting conversation, instead of whatever this is.
I can't imagine the phosphates and nitrogen are especially good for the trees, either. TFA says the wastewater is "treated", but it's not specific on just how much they clean it. Presumably more than nothing and less than enough to return it to the municipal water supply.
Really, how well the forest grows is beside the point. They're doing this to dispose waste water. If they can make a tree crop to offset costs a bit, then great. The "climate change" angle is lipstick on the pig.