The Watershed

Beginning as a small stream that exits Indian Lake from the south, the Great Miami River meanders through seven southwest Ohio Counties and a small portion of southeast Indiana, as it makes its 170 mile journey to the Ohio River.  The river’s drainage basin, or watershed, covers 5,385 mi.2 (~14,000 km2) and drains all or parts of 15 counties.

There are more than 6,600 miles of rivers and streams in the Great Miami River Watershed. There are at least 285 named streams within the watershed, including the Still Water River, Mad River, Whitewater River, Twin Creek, Wolf Creek, and Four Mile Creek.

History

In his Historical Collections of Ohio 19th century historian Henry Howe recounts, “The word Miami, in the Ottawa language, is said to signify mother. The name Miami was originally the designation of the tribe who anciently bore the name of "Tewightewee." This tribe were the original inhabitants of the Miami valley, and affirmed they were created in it.” This and other tribes maneuvered their canoes up the Great Miami and down the Maumee to reach Lake Erie. It was this same route that allowed the first settlers to navigate from the Ohio River to the upper portions of the state. Once the settlers arrived in this region, the Great Miami was a natural waterway for trading purposes up the river from Dayton as well as below.

The settlers along the Great Miami first used flat boats and keelboats for moving trade."The boats were often loaded with produce, taken in exchange for goods, work, or even for lots and houses, because business men, instead of having money to deposit in the bank or to invest, were frequently obliged to send cargoes of articles received in place of cash, south or north for sale. Cherry and walnut logs and lumber were brought down the river by rafts. The flatboat men sold their boats when they arrived at New Orleans, and buying a horse, returned home by land. (Franklin in the Miami Valley, Warren County Genealogical Society).

In March of 1913, the Miami Valley witnessed a natural disaster unparalleled in the region’s history. Three storms converged on the state, dumping 9 to 11 inches of rain March 23-25 on ground already saturated from the melting of ice and snow of a hard winter. A 90-percent runoff rate caused the Great Miami River and its tributary streams to overflow. Every city along the river was inundated with floodwaters. About half a trillion gallons of water flowed down the Great Miami River during the flood. That's equal to about four days' worth of water flowing over Niagara Falls. More than 360 people lost their lives; property damage exceeded $100 million (nearly $2 billion in today’s economy).

Recreation

The Great Miami River is now host to many who love to canoe, kayak, and water ski. in addition to recreation in the water, there is also the Great Miami River Recreation Trail

Geology

It is located entirely within the Till Plains – a Physiographic region known for its large deposits of highly permeable sand and gravel.  This material, left by the glacier over 10,000 years ago, allows for vast amounts of water storage underground, keeping many of its tributaries flowing even during times of drought.  This precious groundwater supply also serves as the drinking water source for hundreds of thousands of southwest Ohio residents.

The level to gently rolling plain is broken by the wide valleys of the major streams. Toward Cincinnati the topography is hilly and more dissected, but is not as rugged as some other parts of southern and southeastern Ohio. The principal terrain features north of Middletown are the kames, eskers, and end moraines left by the glaciers.

Geology

The bedrock units exposed in the basin consist of limestone, dolomite, and shale of Ordovician and Silurian age. These strata are relatively dense and do not allow for the storage of large volumes of ground water. In the northern part of the basin, where the Silurian dolomites prevail, ground-water storage may influence streamflow to a minor degree.
The glacial drift is deep over the upper part of the basin, exceeding 300 feet in places, but thinning toward the south. The glaciers left extensive deposits of washed material, particularly outwash, valley-train deposits, kames, eskers, and kame moraines. Many deep preglacial or interglacial stream valleys are filled with permeable sands and gravels.

Soils

The soils in the basin are derived from glacial deposits of both early and late Wisconsin age. Miamian, Celina, Crosby, and Kokomo are the dominant soils of the late Wisconsin till area, and Russell, Xenia, and Fincastle are the principal soils of the early Wisconsin area. Classification of these soils depends on the drainage condition under which they developed. The less well-drained soils are relatively impermeable. Rather extensive terrace and alluvial soils occur, generally with good drainage and high permeability.
Eldean, Ockley, and associated soils are prevalent on the terraces. Genesee soils are the dominant alluvial soils.

Threats

Since the Clean Water Act was passed in 1972, regulations have limited the discharge of pollutants into waterways, so the water quality in the watershed has shown strong improvement. However, due to stormwater pollution, the everyday actions of every person within the watershed can have an adverse impact on the water quality. Even if you live miles from the local stream, your nieghborhood is still directly connected to it by a network of storm drains or drainage dithes. The storm water, or rain water can pick up debris, chemicals, soil, or other pollutants and carry them through this storm water system directly, and untreated, to the nearest water body.

By becoming a Great Miami River Clean Up volunteer you can help us to reduce the amount of storm water polltion by collecting trash from the banks of the river.

Thank you to Doug Dirksing for compiling some of this information and to Miami Conservancy District, Fish and Wildlife Service and Friends of the Great Miami for providing the background.