Friday, November 02, 2007
Most folks understand right away that when you get five or six inches of rain during a prolonged drought, it’s not nearly enough to make up for a shortfall of 12 inches or more. Simple math.
Most folks also realize that where it rains is also an obvious indicator. But why is it that heavy rain in, say, the next community or county over doesn’t help where you live?
There’s another easy explanation, and you can find it in color. North Carolina has 17 river basins, and if it doesn’t rain a lot in the basin where you live, that water goes elsewhere.
Gov. Mike Easley presided over a briefing the other day to talk about the continuing drought. His advice to North Carolinians: “Don’t spend the rain.”
But nothing was more vivid than a map of where the rain fell from Oct. 24 to Oct. 26.
Displaying county lines (but, alas, not the county names) and an overlay of the river basin shapes, it makes clear that the two main N.C. beneficiaries of the rainfall were the Cape Fear River Basin, running from southern Rockingham and Alamance counties down toward Wilmington, and the Roanoke River Basin, from northern Rockingham and the Southern Virginia counties of Henry and Pittsylvania, got most of the heavy rains. The Neuse River Basin, which includes the population centers of Durham and Raleigh, and the Yadkin-Pee Dee and Catawba River Basins, which embraces the Charlotte region, got far less rain and benefited the same way: not so much. Western North Carolina’s river basins, some of which flow to the Gulf of Mexico via the Ohio and Mississippi rivers, got next to no beneficial rains. So if you’re wondering how much last week’s rains helped, take a look at the map.
Posted by Jack Betts at 1:13 PM