RALEIGH — State officials say a wall of mud that's making its way down the Neuse started in Wake County. The big question is-- where did all of the mud come from? And is it a threat to the already fragile Neuse?

You have to see it from the air to really appreciate how muddy the incoming water is. Crabtree Creek seems to be the source of a dirty stream that's snaking more than 100 miles to the east.

North Carolina Environmental Health official Don Reuter calls the murky waters a plume of tremendous magnitude. He says the dirt reaches from the Triangle areas to the coast-- an event that appears to be unprecedented.

Right now, no one is sure why. But researchers are making a bee-line to local construction sites to see if they're part of the problem. During the rainy season, a moderate amount of soil from construction projects is expected to flow into creeks and streams.

State Engineer John Holley says that doesn't mean that there are notproblems. There may be construction projects that are not taking proper measures. Right now, the state is making sure the projects have good sedimentation control plans.

This could result in fish kills if the dirt robs the water of too much oxygen. But officials say it isn't dangerous to humans. Still, it's another sign of pain for the embattled Neuse River-- a body of water the state is working diligently to protect.

Regulators tell us the fact that there is clay sediment in the water isn't unusual at all. That happens every time it rains just because we have clay in this area. What they're saying is unusual is the sheer amount of the stuff that's in the water stretching all the way out to the coastline.

This could become a permanent thing with as much construction as we have in the Triangle. It could just be a sign of growning pains.

Sky5 Photographer: Gill Hollingsworth