Judging the salinity content of the Cape Fear River is a bit tricky because of its proximity to the Atlantic Ocean.
“The answer to that question is a moving target. The salinity of the river is different based on whether or not the tide is coming in or going out,” said Kemp Burdette, Cape Fear River Watch riverkeeper. “When the tide’s coming in from the ocean, it’s pushing salt water in. When it turns around and goes in the other direction, it’s pushing fresh water out.”
The river’s salt content is also affected by other factors, such as the weather. For example, one side effect of the area’s super-dry summer was a decrease in the fresh water flowing into the Cape Fear.
“When we have a drought in North Carolina, that means there is a lot less water going down all the rivers and all the streams that combine to make the Cape Fear River,” Burdette said. “By contrast, in years with a lot of rain, the river is not as salty.”
Because the river’s salt-water content is dependent on so many factors, it’s difficult to pinpoint a location where the salt concentration is particularly low. However, Burdette said there’s one easy way to gauge the salinity of the river in your area – examine the cypress trees growing along the shoreline.
“They don’t tolerate salt water very well,” he said. “If you don’t see dead cypress trees in your area, that means the water is fairly fresh. It’s not completely fresh. The water is never completely fresh, but it’s mostly fresh.”
That means the river in the Port City is pretty salty, but less so near Castle Hayne.
“You don’t find a lot of dead trees up around Castle Hayne,” Burdette said.
Date posted: October 24, 2011
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