I intentionally took a radical (but possible) example. A more related likely result is NIMBYs using the precedent to give all other ecosystems 'personhood' and strangling housing development in lawsuits. Now that I consider this, judges could use other creative readings of corporate law to actually weaken environmental law (can we use eminent domain on the river? Does it have a natural monopoly on water supply and we need to apply anti-trust?).

Ultimately this is an improper hack, suborning the law for political ends. There are some evils that can justify even a take-no-prisoners approach. But better protection of river ecosystems? Are there really no better ways to achieve that?