Phosphorus entering Lake Eucha has dropped by 14 percent, said Mark Harrison, public information officer for the Oklahoma Conservation Commission.
Harrison said the reduction is the result of implementing certain management practices along Beaty Creek, a Lake Eucha tributary.
Monitoring indicated that the tributary, with a watershed of 60 square miles, or 17 percent of the Lake Eucha watershed, contributed about 40 percent of the phosphorus going into the lake.
The Beaty Creek Water Quality Project was voluntary and involved 71 landowners in Oklahoma and 18 in Arkansas, Harrison said.
To reduce pollution, vegetation was restored to the bank of the tributary, he said.
In other cases, crops were replaced with pasture so the land would not be bare for a portion of the year, he said.
Nutrient management also was conducted, he said.
"Instead of spreading the poultry litter on the ground at all times, some farmers constructed a storage area where it was stored until the proper time to apply it," Harrison said.
Farmers also addressed how animals were watered and fed.
The project cost about $1.5 million, he said.
"Our water quality experts are very excited that it showed this much change in so few years because with soil and water conservation practices, it usually takes a long time" to see results, Harrison said.
The study was released a day after Oklahoma Attorney General Drew Edmondson said he would resume negotiations with poultry industry officials to reduce phosphorus levels from chicken litter in eastern Oklahoma watersheds.
Increased phosphorus causes odor, taste and algae problems in the water.
Janet Wilkerson, a spokeswoman for the poultry companies, said the poultry producers would welcome a similar project.
"I think it is absolutely part of the solution," she said.
A spokesman for Edmondson said his office is reviewing the report.
Barbara Hoberock (405) 528-2465