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In a dredging operation, a Mud Cat™ restored the Cannon Mills holding pond at Concord, North Carolina, to useful firefighting life and Cannon Lake to its original capability of providing a water supply for the Kannapolis water treatment plant.

Cannon Mills officials' first experience with a dredging machine occurred at its #6 plant in Concord. At that time, the Mud Cat™, manufactured by Mud Cat™ Div., Mud Cat International, was being used to remove a 29-year accumulation of silt from the holding pond so that the body of water could be returned to its original state. Since the pond was used in finishing operations as well as in the plant's fire protection system, the silt situation had become serious. The dredge worked for only two months, but in that time it increased the pond's capacity from 1 million gal to nearly 10 million ensuring plenty of plant capacity and an abundance of water for ore protection.

In the second project, working 24-hour days, 6 days a week, the machine dredged Cannon Lake through cold fall rains and a winter snowstorm. Night dredging was done under generator-run lights strung on poles along the shore, plus the lights mounted on the machine's cab. So that operators could spot the projecting sandbars. Although the machine weighs 21,000 lb., it can float in water as little as 21 in. deep.

The Mud Cat™ dredged to an average of 5 ft, going as deep as 8-10 ft where the sandbars were highest and the muck the deepest. In six months, the machine dredged 130,000 cu yd of sediment from the lake's bottom.

A series of terraces were cut from the sides of surrounding hills in a half mile area and the sediment was pumped onto the terraces so that the water could run back into the lake while leaving its sediment. When the terraces were dry, the land was shaped and smoothed for grass planting. The grass stabilized the soil, keeping it from eroding back into the lake.

The dredging project provided additional storage capacity in excess of 28 million gal of water, badly needed by the Kannapolis waterworks and the mill.

Reprinted from Water Engineering & Management