Ask Mr. Smarty Plants

With all the rain, it sounds as if you would benefit from using some sort of erosion control blanket, especially around the pipe. The erosion-control fabric works by slowing the runoff water and allowing sediments to fall out rather than be washed away. Seeds are sown under the erosion-control material and grow up through the matting when they germinate. You can insert plants into the soil by cutting through the matting. The roots of the plants that are growing through the erosion-control material anchor the soil to stop the erosion. If you use erosion-control blankets made of biodegrable material, they will eventually disappear leaving the plants to control the problem. You can read about a stream bank stabilization project implemented by the Department of Environmental Services, Arlington, Viriginia. Although their problem was not exactly the same as yours, they did use the erosion control blankets with great success.

Now for plants to use for erosion control, grasses are ideal because their extensive fibrous root systems hold the soil in place.  Here are some native grasses that are attractive and grow well in South Carolina:

Sorghastrum nutans (Indiangrass)

Chasmanthium latifolium (Inland sea oats)

Schizachyrium scoparium (little bluestem)

Muhlenbergia capillaris (hairawn muhly)

Andropogon gerardii (big bluestem)

Panicum virgatum (switchgrass)

Here are some other plants that should work well:

Parthenocissus quinquefolia (Virginia creeper)

Ceanothus americanus (New Jersey tea)

Coreopsis lanceolata (lanceleaf tickseed)

Rudbeckia hirta (blackeyed Susan)

Vaccinium stamineum (deerberry)

Vaccinium pallidum (Blue Ridge blueberry) and here are photos

Rubus trivialis (southern dewberry)

All of the above plants are native to Aiken County, South Carolina but since I don't know the particulars of your site (e.g., soil type, soil moisture, available sunlight), you need to check the "Growing Conditions" on each of the species' pages to make sure that they match those of your site.

Here are photos from our Image Gallery for the plants listed above:

Sorghastrum nutans

Chasmanthium latifolium

Schizachyrium scoparium

Muhlenbergia capillaris

Andropogon gerardii

Panicum virgatum

Parthenocissus quinquefolia

Ceanothus americanus

Coreopsis lanceolata

Rudbeckia hirta

Vaccinium stamineum

Rubus trivialis