For farmers who rely on the Tuckasegee River to irrigate their crops, a brutal summer heat wave and dry spell took a turn for the worst this month when too much mud in the river forced them to shut down their watering systems.

During the past three weeks, tomato farmers in the Thomas Valley near Whittier have been unable at times to run drip irrigation equipment to counter drought conditions because sediment in the Tuckasegee River was clogging their pumps.

โ€œWith the 90-degree days, itโ€™s really critical that these farms get drip irrigation,โ€ said William Shelton, who runs a vegetable farm in Thomas Valley. โ€œThat riverโ€™s our lifeblood when it comes to these crops. Particularly during drought.โ€

Tomatoes are 85 percent water. When the plants are overstressed, they will actually take water back from the fruit, ruining the crop.

Kent Cochran, who farms 20 acres of tomatoes just up the road from Shelton, doesnโ€™t understand how the river can be full of mud when there is no rain.

โ€œWhen it rains, thereโ€™s going to be mud for a day or two but thatโ€™s not really an issue,โ€ Cochran said. โ€œWeโ€™ve been needing the water bad these past three weeks, and sometimes we go over there and itโ€™s clear, and other days itโ€™s mud.โ€

Robbie Shelton, the Jackson County erosion control officer, has been equally perplexed. Sheltonโ€™s job includes monitoring construction sites that could dump sediment into the river.

Last week, Robbie Shelton traveled up and down the river in search of an answer to the farmersโ€™ questions. The focus of his investigation was Duke Energyโ€™s efforts to restore the streambed above and below the former site of the Dillsboro Dam.

Shelton took pictures during the first week of July that showed the river was clear above the dam and increasingly turbid below.

โ€œThe Tuck upstream of the dam is clear. Itโ€™s downstream that itโ€™s muddy,โ€ Shelton said.

Shelton said during the drought, the river was increasingly muddy as it moved downstream towards Barkerโ€™s Creek.

โ€œThe closer you get to Thomas Valley the dingier it gets,โ€ Shelton said. โ€œItโ€™s a progression. Iโ€™ve tried to find a source, and thereโ€™s not been one thatโ€™s been found.โ€

Nate Darnell, who works an 8-acre tomato field in Thomas Valley as part of his North Face Farm, has tried to bring some levity to an otherwise worrisome situation.

โ€œAs a farmer, I have to deal with a lot of runoff regulations, and it strikes me as ironic that the upstream runoff from development is causing us the problems now,โ€ Darnell said

The restoration of the stream bank at the former Dillsboro Dam site is monitored daily by personnel from Duke Energy in accordance with the Clean Water Act and overseen by the N.C. Division of Water Quality.

Duke has been monitoring turbidity below its work zone. It has not exceeded state standards. In fact it has been well below them, according to Duke spokesperson Jason Walls.

โ€œThe turbidity and the sediment in the river are coming in from other places,โ€ Walls said. โ€œWe feel confident that our operations arenโ€™t increasing the levels of sediment.โ€

If the dam site isnโ€™t causing the sediment, then what is?

Thatโ€™s the question Cochran and Darnell are asking. Darnell has observed that on dry days the river gets turbid in the middle of the day.

โ€œIt was coming on down here about midday, anywhere between 11 a.m. and 1 p.m.,โ€ Darnell said. โ€œI really canโ€™t give you a good reason, but I could speculate.โ€

So far this summer, Darnell estimates he has lost between one and three tomatoes from each of his plants. By the end of the season, those losses could add up to $25,000 in lost crops.

Darnell said farmers are constantly dealing with loss, whether from drought or insects or crows, but having the cause be the river that is the valleyโ€™s lifeblood is mystifying.

โ€œThe riverโ€™s not always going to be clear, but we really shouldnโ€™t have to fight it during drought,โ€ Darnell said.