which is now so overrun with alien species it can no longer support commercial fishing. A city sewage plant outside Los Angeles has contributed so much polluted effluent that it replaced a kelp forest with sludge laced with toxins and heavy metals. The point is that estuary and its tides acted as part of Nature's way of dealing with pollution. So did the kelp forest. Get rid of them and you reduce the ocean's ability to do what we wait it to do - disperse wastes and deal with pollution.