The Susquehanna River is ailing, Pennsylvania regulators say, but they still don’t want to put it a pollution diet, despite more than a decade of reports of cancers and lesions in smallmouth bass in the Chesapeake Bay’s largest tributary.

The state Department of Environmental Protection has once again declined to list the Susquehanna as impaired in a biennial assessment of conditions in the Keystone State’s 86,000 miles of rivers and streams and 161,000 acres of lakes.

The state’s draft Integrated Water Quality Monitoring and Assessment report, posted Friday on the DEP’s web site, acknowledged the river’s health problems, including low dissolved oxygen levels, fluctuating PH levels, increasing levels of herbicides and the presence of endocrine-disrupting chemicals. But state officials declined to recommend the river for a designation that would lead to imposing a timetable for its cleanup -- but which also likely would attract funding from Washington to help. 

Under Section 303(d) of the federal Clean Water Act, states are required every two years to identify waters within their state where current pollution control technologies alone cannot meet the water quality standards set for that waterbody. States must submit a list of these impaired waters, plus any that may soon become impaired, to the Environmental Protection Agency for approval.

Then, they must figure out what pollutants are impairing the waterway and adopt a pollution reduction plan, or total maximum daily load (TMDL).  A similar process was used in classifying the Chesapeake as impaired for nutrients and sediment, which lead to the Bay TMDL giving states’ targets and deadlines for reducing them.

The listing is not the only path toward improvement for a polluted waterway. But much like the Superfund program, the 303(d) listing accelerates money, attention, scientific work and remediation. It also makes identified polluters accountable, with deadlines for cleanup, and spurs enactment of new laws and regulations to curb pollution.

In its report, the DEP said that it didn’t have enough information to designate the Susquehanna as impaired.  State officials also said the river was doing better than others, and that the tributaries of the Susquehanna had higher contaminant levels but lower fish mortality, suggesting they were able to survive the onslaught.

“Preliminary qualitative and semi-quantitative analysis of macro-invertebrate and fish community data do not suggest there are major issues occurring to aquatic life,” the report said. “However, more rigorous analyses are needed to correctly assess the aquatic life and they are currently under development.”

DEP is accepting public comment on the draft report until Sept. 12. On Monday, DEP is holding a webinar to discuss its findings.

This is not the first time Pennsylvania’s DEP has balked at declaring the Susquehanna impaired.

The decision disappointed environmental leaders in Harrisburg, who have been pushing for the river to be listed as impaired since 2005, when the first blotchy bass showed up in the central part of the river.

John Arway, executive director of the Fish and Boat Commission, an independent state agency dedicated to protecting Pennsylvania’s aquatic resources, fish and boating opportunities, has been leading that charge. Arway said he met with acting DEP secretary Patrick McDonnell Thursday night to discuss the report. When McDonnell told Arway the agency still didn’t have enough information to list the river, Arway said he was disappointed but not surprised.

The agency, Arway said Friday, has long worried that industry could sue the state, claiming it had set an unattainable cleanup standard. Those industries include the many in Pennsylvania that discharge into waterways: sewage treatment plants, gas drillers, poultry and egg farms, dairy operations and livestock.

Rod Kime, head of DEP’s water quality division acknowledged as much in a 2013 forum on the Susquehanna’s health that was organized by the Chesapeake Bay Foundation.

"We are a regulatory agency,” Kime said then. “We can be legally challenged…We need good science before we go back to stakeholders and say, 'this is what you have to fix.'"

Arway said he understands the agency’s trepidation, but he’s more concerned about saving the fish before it’s too late. He’s been writing letters to the EPA and newspapers and speaking at forums all across the watershed to push for a listing. The Fish and Boat Commission even started a fundraising campaign to help the river, a rare move for state government.

“I don’t mind being cautious,” Arway said, “but you can get to a point where you become so concerned with the impact of the decision that it affects the quality of the decision you do make.”

Arway’s commission hired the U.S. Geological Survey to collect information that DEP didn’t have on fish habitat at the river’s edges. That work found significant mortality. Arway’s staff biologists have also done their own sampling.  He contended that the state has plenty of evidence of the Susquehanna’s impairment.

Harry Campbell, Pennsylvania executive director of the Bay Foundation, agrees. The environmental group has been pushing almost as long as Arway for a listing.

As Democratic presidential nominee Hillary Clinton and her running mate, Tim Kaine, prepared to visit Harrisburg Friday evening, Campbell stood on the Harvey Taylor Bridge in the state capital, gazing across the wide river at an enormous algal bloom. There may not be conclusive evidence on the causes, Campbell said, but it’s clear the river is impaired. Just look.

“You get to a point in all science where you say, ‘the science indicates.’ It never fully concludes absolutely,” he said. “By listing the river as impaired, it formalizes this concern, so regardless of who is in the governorship, who is in Congress, who is president, this issue will be worked on until the problem is solved.”