Within the Kokosing was originally published in the BFEC Newsletter, Vol. 14/No. 4, Fall 2010.
If you live in the Kokosing River watershed, then finding one of the highest quality rivers in the state of Ohio may be as easy as looking out the nearest window.
Based on extensive data collected in 2007, the Ohio Environmental Protection Agency (Ohio EPA) has completed a report on the health of the Kokosing River and concluded that the river is one of the best in the state.
The Ohio EPA surveys rivers to determine if our waterways are meeting water quality standards and if a river's health has changed over time.
The agency takes a comprehensive view by measuring water chemistry, physical habitat (such as steam bottom composition or damage by livestock) and biological life.
In the Kokosing study, 53 sampling stations were used to sample water and the “fish and bugs” that are used as biological indicators, or “bioindicators” of water quality. Ohio has led the nation in the use of bioindicators, based on the overall biological diversity of the river as well as the types of fish species and macroinvertebrate (or "bug") species that are present.
If a stream or river is polluted or altered by human activities, diversity tends to decrease and the species that are sensitive to disturbance tend to disappear from that location. Bioindicators are often more valuable than chemical analysis of water samples because they integrate all of the conditions of the stream, particularly those that change over time.
The Kokosing River and its tributaries (like Center Creek, Dry Creek, Big Run, Jelloway Creek and Schenck Creek, to name a few) are brimming with sensitive fish species. A few highlights include:
Redside dace (Clinostomus elongatus) is a colorful fish that is threatened or endangered throughout much of its range. These are visual surface feeders that feed primarily on terrestrial insects (that fall into the water), so they must have clear flowing water with overhanging vegetation in order to survive. Their specialized feeding habit means that they are quite sensitive to human alterations to the environment.
Bluebreast darters (Etheostoma camurum) depend on fast flowing water over gravel in order for their eggs to hatch. While they have been present in the Kokosing for some time, their numbers have increased and their distribution within the watershed has expanded as water quality has improved. At one location nearly 200 bluebreast darters were caught (and released!).
Northern pike (Esox lucius) are in large part limited to western Lake Erie, a few of its tributaries and a few small populations in rivers such as the Kokosing.
If you’ve ever tied a fly in order to flyfish the Kokosing, then you’ve mimicked one of the best bioindicators of clean water that we have, the mayfly. Mayflies belong to a much larger group known as the benthic invertebrates. These are small animals that live on the stream bottoms (benthos), are visible to the naked eye (macro) and are without a backbone (invertebrate). This group includes crayfish, freshwater clams and snails, and the immature forms (e.g., nymphs) of terrestrial insects such as mayflies and dragonflies.
Benthic invertebrates make good indicators of stream health because they are easy to collect, they differ widely in their tolerance to pollution and habitat changes, they don’t move around much and they integrate the varying environmental conditions they experience over time. Many invertebrates are very sensitive and disappear from a river if it becomes polluted with excess nutrients or sediments, or if the water becomes too warm, for example if the riparian (streamside) trees are cut allowing more sunlight to reach the water.
In the highest quality areas of the watershed, between 80-86 macroinvertebrate species were collected at each sampling site! This is a remarkable level of diversity and is an indication of the exceptionally clean, cool, highly oxygenated water that we have in the Kokosing.
A diversity of freshwater mussel species was also found. The U.S. Fish and Wildlife Service calls freshwater mussels our “hidden treasure;” they cannot make sounds or see, they seldom move and they may live for decades. The U.S. leads the world in the diversity of mussels it supports.
While all the European countries together claim only 12 species, in the U.S. there are nearly 300 native species. Historically, Ohio alone supported 80 different species, representing 27 percent of all species known in the U.S. And of all the different types of freshwater species in the U.S., mussels are among the most endangered group. It is estimated that about 70 percent are listed as extinct, endangered, threatened or of special concern.
Because mussels are sensitive to habitat changes they are considered barometers of stream health and stability. Their declining populations are largely the result of habitat changes including sedimentation, toxic pollutants and altered patterns of river flow. Dam building is a significant cause of the loss of species, and the occurrence of dams in Knox County are no exception. Despite this, the Kokosing River supports a variety of species.
Mussels are an important part of a river’s food web; a river system with abundant mussels typically supports more muskrats, otters, wading birds, and game fish. The creeper mussel (Strophitus undulates) is one example of a species that is found in the Kokosing but is thought to be imperiled in other states. [Sources: www.dnr.sc.gov/cwcs/pdf/Creeper.pdf, www.glooskapandthefrog.org]
Why is the Kokosing so healthy? Many factors have helped preserve this jewel of biodiversity. The fact that the watershed is primarily agricultural without large urban areas reduces the pressure on our waterways.
Another benefit comes from the abundance of streamside, or riparian, forests along much of the length of the river and its tributaries. These riparian forests help buffer the stream from pollutants, their shade cools the water, and the leaves they drop in the fall form the basis of much of the stream’s food web. They also protect the floodplain from eroding during floods and in doing so also protect downstream residents. (See page five of the newsletter to learn more about one of our seminal streamside tree, the sycamore.)
Given the benefits that come from protecting streamside forests for people and the river, the residents of Knox County are fortunate that a network of organizations have taken on this work, including the Knox Co. Park District, Knox Soil & Water Conservation District, Ohio Dept. of Natural Resources - Scenic Rivers Program and Owl Creek Conservancy. Within its preserve, the BFEC also protects two miles of river bank.
Despite the above, there are areas of the watershed that have been heavily impacted by human activities. The Ohio EPA found that about twelve percent of the sites it sampled were impaired, including some locations on Dry Creek, Jelloway Creek and on the Kokosing itself.
Threats to the river that are causing problems include livestock near or in the waterways leading to bank erosion that high bacterial levels. Agricultural activities can lead to sediment and nutrient runoff. High nutrient levels also result from municipal wastewater discharge.
Supporting the protection of streamside forests and the organization doing that work is a good way to help ensure our beautiful Kokosing River stays that way. But there is more that individuals can do, and that starts by defining an important term we've used in this article: "watershed."
A watershed is the area of land that drains into a particular body of water. If you live anywhere in the 485 square miles that encompass the Kokosing watershed (including Mt. Vernon, Gambier, Fredericktown, Danville, and Chesterville), then runoff from rain that falls on your roof will collect into ditches, then creeks and streams, and eventually empty into the Kokosing River.
Water has a habit of picking up anything lying on the ground on its way to the river, including exposed dirt from farm fields and construction sites, (which can get washed into rivers by the 100's of tons), or car fluids dripped onto parking lots.
Being mindful of potential runoff pollution can help. For instance, applying fertilizer to your lawn before a heavy rain may result in much of it being washed into the river, where it feeds algae and later depletes the water of oxygen. A better alternative: lightly water the fertilizer into your lawn with a hose, thereby controlling the water and limiting how much of it (and the fertilizer) leaves your property.