A large algae bloom on the Penobscot River is likely to soon recede as temperatures drop. The damage done to relations between the Penobscot Nation and the Maine Department of Environmental Protection, which for nearly a decade have been at odds over water quality regulation, will take longer to fix. Regulators can restore the tribe’s, and the public’s, confidence with tougher regulations and more frequent monitoring of mills on the river, especially Katahdin Paper Co., the source of the bloom.

An independent assessment of what went wrong would also help ensure such problems don’t recur. The DEP shouldn’t do this assessment because it writes the mill’s permits and ensures it complies with them.

After a large algae bloom on the Penobscot in 2004, Katahdin Paper, which operates the former Great Northern Paper Co. mills in Millinocket and East Millinocket, agreed to stop using phosphoric acid as a bleaching agent at the Millinocket facility, according to the DEP. The company says it agreed to reduce, not eliminate, the use of phosphoric acid and did cut its use by more than half. The company was also required to report its phosphorous discharges into the river at the end of the summer, but no limits on phosphorus discharges were set because the DEP believed the company had stopped using the chemical. Phosphorous can trigger large blooms of the potentially toxic blue-green algae during the warm summer months when water levels are low. The algae can take up much of a river’s oxygen, choking off fish and other species.

Accepting a voluntary agreement and requiring testing only at the end of the summer – when it would be too late to stop a bloom – were mistakes. However, if the DEP mandated phosphorus elimination, it would have been criticized for harming a newly restarted mill in an area heavily dependent on papermaking.

This spring, the company began using or increased its use of phosphoric acid at its Millinocket facility due to concerns about the brightness of the paper made there after the company switched to a new pulp supplier. Inexplicably, the company did not notify the DEP of the change, according to Andrew Fisk, director of the department’s Bureau of Land and Water Quality.

In July, as part of water monitoring, officials from the Penobscot tribe, DEP and Katahdin Paper collected samples along the Penobscot River. That is when the bloom was discovered. It spread from Dolby, near the mill, to Hampden by the time the DEP sent out a violation notice to the paper company last week. Whether the company will face financial penalties for reducing oxygen levels in the river will be determined later. Toxicity tests on the algae are ongoing.

Earlier in August, the 1st Circuit Court of Appeals affirmed that the state has the authority to regulate water quality on rivers that pass through tribal lands. The long-simmering legal dispute caused tensions between the state’s tribes, which wanted the federal government because it has a larger responsibility to the tribes to retain this authority, and state environmental regulators and paper mills.

The timing of the algae bloom, soon after the court ruling, reopens the debate over whether the state is capable of regulating water quality. To the tribes, the fact that the DEP allowed the mill to get by with a voluntary agreement instead of banning phosphorous discharges and closely monitoring discharges to ensure it wasn’t being used shows that the state can’t be trusted to protect tribal waters.

Although the 1st Circuit upheld Maine’s authority to regulate water quality in tribal lands, it warned that the U.S. Environmental Protection Agency could overrule the state if it did not adequately protect tribal rights, such as fishing. “If Maine is wise in its exercise of its new authority, quite possibly these questions will not need to be resolved,” the court wrote of federal pre-emption.

The wiseness of the state is now in doubt.

The DEP is writing its first licenses for paper mill discharges into the Penobscot River, licenses that must now be more stringent because of this incident. Consultation before mills change their manufacturing process and frequent monitoring and reporting of all chemicals discharged into the river should be requirements of those licenses.

In the meantime, having another entity examine what missteps were made and by whom would clarify whether the state is capable of fulfilling its water quality regulation obligations.