By MICHELE F. MIHALJEVICH
Indiana Correspondent MONTPELIER, Ohio — As levels of phosphorous in Lake Erie increase, the condition of the lake suffers, a water quality expert said last week.
After years of improvement in the lake’s water quality, the situation began to decline in the mid-1990s, said Pete Richards, a senior research scientist with the National Center for Water Quality Research at Heidelberg University in Tiffin, Ohio.
“We’ve had more nutrients available for more algae growth. Blue-green algae is back with a vengeance,” he said March 15, during the Tri-State Conservation Farming Expo in Montpelier.
Farmers can help reduce phosphorous levels in the watersheds of rivers that empty into the lake by reversing a trend of applying fertilizer and manure in the fall and winter and on frozen ground, Richards noted.
“Fertilize in the spring if possible, and watch the weather and don’t apply when rain is likely,” he said. “Know your fertilizer levels and don’t over-apply it. And consider precision application of the fertilizer that’s linked to variations within the field.”
Ironically, no-till, which has benefits for farmers and the environment, could be a part of the problem because a lack of tillage may be keeping phosphorous on and near the top of the soil, Richards explained.
After the Cuyahoga River, which flows into the lake, received national attention by catching fire more than once – including in 1969 – the lake was labeled as dead by many, Richards said, adding those fires were generally caused by grease and oil on the river’s surface. At the time, the lake’s harbors were contaminated, and oil, grease, mercury, iron and polychlorinated biphenyls (PCBs) could be found in its waters.
Invasive species, such as lampreys, were also found, and over-fishing decimated the lake’s walleye and blue pike populations, he added. Probably the biggest problem for the lake was an area of anoxia, or no oxygen, found in its central part, Richards said.
“They decided they had to control the phosphorous in the lake and make it the limiting nutrient, which would help cut back on the algae,” he stated. “They reduced phosphorous inputs by banning phosphorous in laundry detergent and by upgrading the sewage treatment plant.”
Officials also looked at nonpoint source pollution in the area, better fertilizer and manure management, and implemented erosion prevention such as conservation tillage and buffer strips. Over time, the quality of the tributaries and the lake improved, as sediment and total phosphorous were down, and the anoxia began decreasing, Richards said.
“These were good signs the programs we implemented were successful in doing the things we thought they would,” he noted.
Since about 1995, however, there are a number of signs the problems are returning. The anoxia has returned and the levels of particulate and dissolved reactive phosphorous are up.
The public sees photos of the blue-green algae and may focus on agriculture as the primary cause of it, said Jim Lake, district support specialist for the Indiana Department of Agriculture’s Division of Soil.
“Sixty-six percent of the land use in the western Lake Erie basin is in cultivated crops, and because of that, we are a player and the issue has the attention of people who don’t farm. Guess where they’re pointing their fingers,” Lake explained.
“It’s important for us to be proactive. The perception of the public, regardless of how accurate it is, is their reality.”
Lake Erie covers 9,910 square miles and holds 128 trillion gallons of water, he noted. It provides drinking water for three million Ohioans and holds 2 percent of all the fresh water in the world. It also supports a $1 billion annual sport fishing industry.
Richards doesn’t expect to see any improvement in the quality of Lake Erie’s water in the near future. “The projected increase in intensity of storms will lead to increased erosion. The projected warmer winters may increase winter rains and lead to the loss of surface-applied nutrients. I think things are likely to get worse, not better,” he said. |
