< 



Buffers are most often left intact 

 because the land was too wet or too steep 

 for development, says Gilliam. "Nature 

 just kind of protected herself." 



But if the present buffers work so 

 well and are largely intact, why are we 

 having fish kills, algal blooms and cries 

 of sick rivers? The problem literally 

 flows from the remaining 20 percent that 

 is unprotected. According to Bledsoe, 

 about 5 percent of the land without 

 buffers is near urban development. The 

 remainder is near animal or agriculture 

 farms. And often these fields or pastures 

 border directly on a creek or stream. 



Although North Carolina has 

 developed best management practices 

 and cost-share programs to reduce 



nonpoint source pollutants from 

 fertilizers, animal wastes and eroding 

 streambanks, water quality problems 

 loom. And development along the 

 state's waterways and wetlands 

 continues at a pace faster than ever. 



So statistics like Wendell 

 Gilliam's — and the fact that trees and 

 grass are cheap and easily maintained 

 — make many who want to solve water 

 quality problems sit up straight and 

 listen. 



People across the globe are 

 interested in buffers, and regulators in 

 North Carolina are no exception. In the 

 past year, Gilliam has given talks, done 

 research and testified before state 

 committees. 



Now that regulators are consider- 

 ing mandatory buffer laws or voluntary 

 buffer maintenance and repair pro- 

 grams, they need the facts: How many 

 feet of grass do you need? How many 

 feet of trees? What species of trees and 

 plants do you have to grow? How 

 much is all this going to cost? 



But, as Gilliam says, "We really 

 haven't gotten that far. I wish I had all 

 the answers for people." 



Scientists hope to have many 

 questions answered by the end of the 

 year. In particular, they'd like to see a 

 formula for determining the proper 

 buffer width for particular soils and 

 regions. In the meantime, Gilliam has 

 recommended that a 50-foot buffer will 



• Cropland 



Sediment, 

 fertilizer and 

 pesticides are 

 carefully 

 managed. 



• ZONE 3 

 Runoff Control 



Concentrated flows 

 are converted to 

 dispersed flows 

 by water bars or 

 spreaders, facilitating 

 ground contact and 

 infiltration. 



• ZONE 2 

 Managed Forest 



Filtration, deposition, plant 

 uptake, anaerobic denitrification 



and other natural processes 

 remove sediment and 

 nutrients from runoff 

 and subsurface flows. 



• ZONE 1 

 Undisturbed 

 Forest 



Maturing trees 

 provide detritus to 



the stream and 

 help maintain lower 

 water temperatures 

 vital to fish habitat. 



• Stream Bottom 



Debris dams hold detritus 

 for processing by aquatic 

 fauna and provide cover 

 and cooling shade for fish 

 and other stream dwellers. 



14 



JULY/ AUGUST 1996 



