SYRACUSE HANCOCK INT'L AIRPORT

Onondaga Creek crashes toward drought as an airport's pollution load looms larger

Onondaga Creek has fallen fast over the past two weeks. At the Dorwin Avenue gage, flow dropped from 43.6 to 18.8 cubic feet per second and gage height slid from 2.43 to 1.57 feet, tracking a week in which the county's abnormally-dry footprint jumped from a quarter to 85 percent of its land area. Syracuse Hancock Airport, eight kilometers off, has logged only 1.5 inches of rain this month against a normal of just over three, with highs running a couple of degrees warm. The watershed above the gage covers only 88.5 square miles, small and quick to respond, which is exactly why a rain deficit that a larger river would barely notice can knock this creek down by more than half in fourteen days. The timing is unfortunate. The creek's upper and middle reaches are already listed as impaired and are still waiting on a federal pollution budget. Less water moving through the same channel means whatever nutrient and organic load it carries has less flow to dilute it, and less turbulence to keep it oxygenated, though the actual dissolved-oxygen and water-quality readings needed to confirm that effect here aren't in hand. The local insect records can't fill that gap. A handful of mayfly observations came in across Onondaga County this summer, but they sit apart from the story: Giant Mayfly and its close relatives were all logged on a single day in late June near Cicero, well off Onondaga Creek, while scattered single records of Red Speckled Dun and Common Square-gills came from Skaneateles, Oswego, Fabius and Moravia. All are community-science sightings still awaiting identification review, and each one marks a species being present at a spot on a date — not abundance, not condition, not a trend. The clean-water reputation mayflies carry as a group doesn't transfer neatly to this particular mix either: Caenis tolerates silt and low oxygen, and Callibaetis is a still-water genus. None of these records fall on the impaired reach, so none of them can speak to what a falling, warming creek is doing to it. What does change the calculus is the Syracuse Hancock International Airport discharge, which entered this month already flagged for a biochemical oxygen demand violation that has tripled twice in three quarters, a trajectory covered in an earlier report on the airport's oxygen-demand violation. Less water in the receiving creek means the same permitted discharge has less flow to dilute into, a concern worth watching even without direct downstream water-quality measurements yet in hand. The airport is also the subject of a SEQR determination notice tied to its 2040 expansion, which puts a facility with an active, worsening water-quality violation at the center of a live development decision on a waterway that is currently running at less than half its normal flow.

Airport's oxygen-demand violation triples, then triples again

Wastewater discharged from outfall 004 at Syracuse Hancock International Airport has exceeded its permitted biochemical oxygen demand limit for three consecutive quarters, and each reading has been worse than the last: 213% over limit in December, 980% over by March, and 4,600% over limit in a sample logged this month. Biochemical oxygen demand is a measure of how much organic material in a discharge will consume dissolved oxygen as it decomposes; violations at this scale, and on this trajectory, point to a treatment process that has broken down rather than a lab anomaly or a single bad reading. The airport is now one of seven facilities listed in significant non-compliance among 80 permitted dischargers tracked in this watershed. No instream water-quality data has yet confirmed what this is doing to dissolved oxygen levels downstream of the outfall, so at this point it remains a regulatory trend rather than a documented fish kill or oxygen crash. But it is arriving in a watershed with little margin left to absorb it. Eleven of the nineteen water bodies assessed within five miles of the airport are already impaired, including both basins of Onondaga Lake, which remain under active remediation for decades of industrial and municipal pollution. An oxygen-demand violation escalating this fast and going unaddressed is exactly the kind of stress that hits gill-breathing and oxygen-sensitive aquatic life first, and it tends to stay invisible until it surfaces as a fish kill or an algal bloom. In a watershed already carrying this much impairment, there is little buffer left before a treatment failure like this one starts showing up in the water itself, rather than just in the compliance record.