(Washington, DC) — Invasive species are a major source of impairment to many of America’s waters, but states are not addressing this problem in consistent ways under the federal Clean Water Act, according to a report by the Environmental Law Institute. The Role of Aquatic Invasive Species in State Listing of Impaired Waters and the TMDL Program uses a sample of seven states with differing invasive species problems, finding that some states list every water segment damaged by these species, while others list none at all. Some states treat invasive species just like chemical pollutants, while others identify them as a cause of harm but not as pollutants that require preparation of Total Maximum Daily Load (TMDL) cleanup allocations. Interestingly, each state has at least some water quality standards that can be used to assess impairments due to invasive species, and most of them have done so at least a few times during the past decade. The U.S. Environmental Protection Agency has not taken a firm position on whether invasive species are pollutants that require preparation of TMDLs, but it has approved state decisions to do so.
ELI staff attorney Adam Schempp notes that “identification by states of waters impaired by invasive species is desirable because it informs the public of the seriousness of the problem and provides a basis for action however the state chooses to classify the impairment.” Compelling evidence shows that invasive exotic species have already exacted a toll on the environment and the economy. These invasive species — Eurasian watermilfoil, carp, zebra mussels, mitten crabs, various algae, etc. — have been responsible for declining native fish populations, reduced dissolved oxygen, rising water temperatures, increased sediment and nutrients in the water column, beach closures, impediments to boating and swimming, damage to water intakes, and other degradation.
ELI’s study, supported by EPA’s Office of Water, shows that water quality regulators in Washington, New York, Massachusetts, Iowa, Ohio, and California have integrated at least some invasive species assessment into their water pollution programs. But different approaches have been used in different states. Washington and Massachusetts each identify hundreds of invasive-affected waters, but do not treat invasive species as “pollutants,” while California does consider them to be “pollutants” and has more stringent criteria for listing, and consequently far fewer listings. Florida, in contrast, has kept its invasive species programs separate from the water pollution programs, not listing any waters as impaired by invasive species for pollution control purposes. “It’s important for states to recognize impairments associated with invasive species,” says Schempp, “otherwise, opportunities to protect and restore waters may be overlooked or become disconnected from traditional pollution control efforts focused on the same waters.”
The report may be downloaded for free at http://www.elistore.org/reports_detail.asp?ID=11298. For more information, contact Adam Schempp at (202)-939-3864 or Jim McElfish at (202)-939-3840.