Turns out an astonishing number of critters can live in a drainage ditch.
Some science students at Greenup County High School found that out Friday when they trekked out to the field between the football stadium and the school’s entrance road to take water and soil samples from the channel that drains it.
From the gravel and muck they dredged up, the students sorted out dozens of water-borne wigglies — multi-legged hellgrammites, which are the larvae of dobson flies, other, smaller larvae of midges, beetles and black flies, and a multitude of aquatic worms.
The students also found out that what lives in the ditch tells a great deal about the water that runs through it, and by extension about the land it drains.
The field day was a wide-ranging stream study that brought in Morehead State University students to lead segments on water quality, soil identification, land use practices and watershed mapping, among others.
The MSU students, all education majors, got field experience in working with teenagers, which is what most of them will be doing in their professional careers.
“We’re so used to being students that we don’t know how to interact yet on a non-student basis,” said Leighann Switzer, an MSU sophomore from Jessamine County.
Funded by a NASA grant through the Center for Environmental Education at MSU, the exercise was one of many across Kentucky conducted through state and private colleges and universities, said April Haight, director of the center.
It was a day for bare feet and dirty hands. A group of students under the direction of MSU sophomore Katie Combs dug out soil samples from the stream bed and the bank nearby and Combs showed them how to identify it using their hands and a flow chart.
Moistening a chunk and squishing it in their hands, then picking off a fragment and wetting it some more, the students determined by feel whether the sample was smooth or gritty, cohesive or fragmented, and that provided clues about its composition.
Using nets, the students waded into the stream, churned up its sediment and fished out samples they emptied into plastic dishpans.
Using tweezers and their fingers they teased out the animals hiding among the stones and clumps of mud. Some, the midge larvae for instance, were tiny; others such as the hellgrammites, were the size and general shape of centipedes and scuttled away from grasping tweezers.
Once sorted, they filled an assortment of glass vessels that a proficient observer could use to draw conclusions about the health of the stream.
The profusion of worms, for instance, indicates a lack of oxygen, because the worms are tolerant of the lower oxygen levels, Haight said.
Lower oxygen levels, in turn, provide clues about the land that drains into the stream. It could indicate excessive amounts of nutrients entering the water, possibly from fertilizers or septic tanks, she said.
“We’re using procedures that are more advanced than we do in our average classes,” said Greenup senior Strait Taylor. “Learning skills like titration will be useful for furthering my science study,” he said.
The data collected Friday will be recorded and incorporated into a nationwide NASA water quality database, said Greenup biology teacher Justin Stafford. Over time the collective efforts will provide a good picture of local water quality, he said.
Attention to water quality is as important as ever because after several decades of improvement quality has started a downward trend, he said.
Although many of the most egregious industrial pollution sources — called point-source pollution — have been identified and controlled, there is a growing concern about non-point-source pollution, he said.
That means pollution from runoff, drainage, seepage and precipitation.
MIKE JAMES can be reached at firstname.lastname@example.org or (606) 326-2652.