From its humble beginning at the base of the world's busiest airport in Atlanta, the Flint River quickly transforms into one of the most beautiful and scenic riverine environments in Georgia. The watershed of the Flint encompasses 8,460 square miles of Georgia's Piedmont and Coastal Plain physiographic provinces. Within its watershed, the Flint can be clearly subdivided into three unique riverine regimes based on landscape, channel characteristics, flora, and fauna.
The upper part of the Flint flows through the red hills of Georgia's Piedmont physiographic province where it has etched deeply into the crystalline rocks that underlie this region. As the river crosses the fall line near Culloden, its channel geometry changes from deeply incised to a broad, forested swampy floodplain. This middle section of the Flint extends from the fall line to Lake Blackshear near Cordele. South of Lake Blackshear the river landscape again changes. In this, the lower section, the Flint has eroded well into the limestone rocks that form the Upper Floridan aquifer in southwest Georgia. This lower section of the river is home to the city of Albany, GA. Albany is the largest community within the lower Flint River Basin.
Remnant bedrock in the river channel forms the lower Flint River's characteristic limestone shoals. Large slabs of limestone can also be seen piled up at the river's edge. These piles are often remnants of dredging activity that occurred during the late 1800s and early 1900s to keep a navigable channel open from Albany to the Gulf of Mexico. During this era, barges operated to transport cotton and turpentine from this region. Since maintenance dredging ceased, storms have reintroduced limestone debris to the river channel, restoring shoal habitat and making the lower section of the Flint River, once again, non-navigable by larger boats.
Although many view shoals only as hazards to outboard propellers, shoals provide important habitat for many of the Flint River's unique species of animals and plants. One would think that taking up residence in the middle of a rocky river channel would be living dangerously, yet a variety of plants can be found growing on the exposed rocks.
The underwater habitat around shoals is also unique and hosts an impressive diversity of animals, many of which are dependent on this habitat. Scour points that form on the downstream side of rocks offer protected pockets in the streambed ideal for colonization by filter-feeding mussels. Back eddies offer a resting place and good foraging habitat in otherwise rapid currents. A number of rare and threatened fish such as the Halloween darter, grayfin redhorse, and bluestrip shiner, thrive in and around shoals. Hellgrammites, large insect larvae, live and hunt around submerged rocks. Shoal habitat also supports numerous crawfish species, which feed on nutritious organic matter that accumulates on these structures. Both hellgrammites and crawfish are major prey for the shoal bass, a rare species of bass uniquely adapted to shoals and a prized game fish of the Flint River. When the river is low and clear, shoal bass can be seen just below the shoals, waiting in ambush for unsuspecting prey.
The given coordinates will take you to an overlook at the Flint Riverwalk. Here you will have an excellent view of the river shoals.
To get credit for this Earthcache, please post a picture of you and your GPS with the Flint River shoals in the background (optional) and send an email via my geocaching.com account answering the following questions (NOT optional!):
1. What type of rock are the shoals made of?
2. Why would a town such as Albany develop near a river shoal?
3. Standing at the posted coordinates and facing the river, you will see a bridge to your right and a bridge to your left. What kind of bridge is to your left?
4. From the posted coordinates, use your GPSr to measure the approximate length of the shoals down the river.
Note: when the river is up it can be hard to see the shoals. Just do the best you can and estimate the length, it doesn't have to be exact.
Do not post answers in your log. Finds logged without a photo posted and answers sent will be deleted unless prior approval is granted.