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Neuse Riverkeeper Samantha Krop is encouraging Durham residents to reach out to their city council members after the amount of sedimentation in Lick Creek skyrocketed this week.

“There are ongoing Clean Water Act violations in the Lick Creek watershed, and the only people who can do anything about it are on the Durham City Council, which continues to approve developments in this 22.9-square-mile watershed in the absence of stronger ordinances being put in place,” Sam said.

Rain over the weekend washed a shocking amount of sediment from housing developments currently under construction into Lick Creek’s tributaries, which was then carried into Lick Creek.

“The levels that I measured on Tuesday of this week were the highest they’ve ever been. It was really bad in four separate areas,” Sam said. “This issue seems like it’s not only ongoing, it’s getting worse as we get more rain. A rainy season, land clearing — unfortunately, this is going to be getting worse, if action isn’t being taken.”

Worse translates to turbidity readings of 2,000 FNU (Formazin Nephelometric Units, a measurement of scattered light in water), where the state standard for surface waters for rivers and streams is 50 FNU. That’s approximately 3900% higher than the state standard. (The state measures in NTUs, Nephelometric Turbidity Units, and the measurements are similar. The reason Sam has different measurements is that the device she uses to measure turbidity in NTUs does not register anything over 1,000 NTUs and gives an error reading instead.)

Turbidity is the relative clarity of a liquid. It is the measurement of the amount of light scattered by material in the water when a light is shined through a water sample. The higher the number, the less light is penetrating the water, which decimates ecological productivity, recreational values and habitat quality. In streams, like those near housing developments currently under construction in the Durham area, increased sedimentation can result in harm to habitats for fish and other aquatic life. Particles also provide attachment places for other pollutants, notably metals and bacteria, which keep pollutants in the water instead of settling in the soil. Turbidity readings are therefore used as an indicator of potential pollution in a water body, according to the United States Geological Survey website.

One fix for turbidity is a substance called flocculant, which is recommended to developers by Durham Sediment and Erosion Control to stem the flow of sediment from clear-cut development sites. The chemical binds with sediment, weighing it down so it will sink, rather than float in water, decreasing turbidity. Sam said it’s being used by developers, but, based on her sampling, it isn’t working.

“Flocculant is something that developers are willfully using now. My concern is that this is one of the things that would be required if Durham passes the amendments to their unified development ordinance, but we’re seeing people willingly using flocculant, and it’s not working,” Sam said.

Sam is asking Durham residents to reach out to their city council members — send them an email or give them a call — to ask them to protect Durham’s waterways. Contact information can be found HERE.