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Fourteen months have elapsed since the U.S. EnvironmentalProtection Agency rescinded approval of Vermont s legal limit onthe daily amount of phosphorus entering Lake Champlain. Since then,data collection and technical studies have flooded the Champlainbasin, but lake-area residents are growing frustrated with thestate s failure to take substantive steps to thwart thephosphoros-induced blooms of toxic blue-green algae that willlikely return this summer to threaten fishing, beaches and drinkingwater supplies. Two sets of working groups are under way, one evaluating lake waterquality and one engaged in watershed analysis. EPA projects thattechnical reports will be available for public review by the end ofsummer, then the draft Total Maximum Daily Load (TMDL) limit forphosphorus will be released sometime in 2013, but we haven t puta fine date on that, says Lynne Hamjian, surface water branchchief of EPA Region 1 (New England). The EPA s disapproval decision, which arose as a result of alawsuit by the Conservation Law Foundation asserting that the priorstandard contained insufficient assurances for water qualityprotection, contains no definitive deadlines. Once the TMDL isestablished by the EPA, it will be up to the State of Vermont todetermine how to reduce total phosphorus loading to meet thestandard. The state can require reductions from any of the majorphosphorus contributors, including sewage treatment facilities,stormwater systems, and agricultural land uses. Capt. Gil Gagner, proprietor of Bronzeback Guide Service andlifelong resident of Highgate Springs, says last summer brought theworst water conditions in Mississquoi Bay he s ever seen. Crayfish are crawling up out of the water," he says."Clams died by the hundreds of thousands, just washed up andpopped open and died. It was really bad. The state knows about itand they re not doing anything. Gagner is not optimistic aboutthat the present round of studies will lead to substantive change. I m discouraged, he says. Till the money runs out theywon t stop studying. If somebody pisses at the top of the hill andit runs downhill, do you need to study that? Stench and weeds Phosphorus is a nutrient, one of the three elements — alongwith nitrogen and potassium oxide that make up the typical lawnand garden fertilizer. Excess nutrients brought into the state inthe form of cattle feed or fertilizer have to go back out again, orthe nutrient cycle becomes unbalanced, explains Eamon Twohig, asenior research technician at UVM s Department of Plant and SoilScience. We either have to ship enough milk out of the region to make upfor those nutrients coming in, or it gets dumped in the lake, Twohig says. Vermont s soils are generally phosphorus-rich, so excessphosphorus additions from cow manure and chemical fertilizers flowsdownhill until it enters Lake Champlain. In shallow waters likeMississquoi and St. Albans bays and the south lake region, sunlightand warmth combined with this nutrient runoff produces thick cropsof underwater weeds. It s not like it used to be when I was a kid, says JerryHayden, administrative assistant at Community College of Vermont inSt. Albans and a lifelong fisherman of St. Albans Bay. We wentdown to Black Bridge and caught huge fish, and it was crystal clearwater. Now you can just about walk on it out there. If it gets hot,the weeds grow right out of the water, then there s stuff on topof the water that floats and stinks real bad. That stench comes from blooms, or colonies, of toxic blue-greenalgae called cyanobacteria, which are sensitive to the ratio ofnitrogen to dissolved phosphorus, called the "RedfieldRatio." Healthy water bodies worldwide have about 16 to 20parts nitrogen to every part of phosphorus. When excess phosphorusbrings the ratio closer to 10 to 1, cyanobacteria growth explodes. The smell is horrendous, especially when that algae goesblue-green, says Gil Gagner. His community of Highgate Springssits right on Mississquoi Bay, and when it smells bad, peopleleave. Some of the tourists leave and move inland. They just can tstand the smell. It s difficult to predict the blooms, which vary in intensity fromyear to year, but the trend is clearly towards worseningconditions. Last year there were significant blooms. They werevery dense and lasted a long time, says Louis Porter, CLF slakekeeper. Over the long term, there s no question that we areseeing bigger and longer-term blooms. Safe drinking water standards The smell is not the worst characteristic of cyanobacteria: It istoxic to humans and animals. Approximately a quarter-millionhouseholds draw drinking water from Lake Champlain, although thepublic drinking water intakes are not near the warm, shallow areaswhere cyanobacteria is found, according to Maureen McClelland,senior public health adviser for drinking water for EPA Region 1. Summer homes and camps that are not on public drinking watersystems may pull water from the bays where cyanobacteria lurk, andshould be attentive to any alerts posted by the Vermont and NewYork state health agencies. Cyanobacteria has caused the death of pets who drank the infestedwater, and researchers have linked the toxins released byblue-green algae to negative health effects ranging from skinirritation to liver and kidney damage and cancer. There s a lot of anecdotal information about cyanobacteria. Somepeople in New Hampshire are studying a nexus between Lou Gehrig sdisease and these toxins, McClelland says. They are definitelya concern. Although the World Health Organization sets stringent limits forcyanobacteria in public drinking water supplies, the EPA has notyet regulated cyanobacteria under the Safe Drinking Water Act.Three cyanotoxins are on the EPA s Contaminant Candidate Listbeing considered for future public drinking water supply testing,but moving from consideration to regulation is a slow process. Oncethere is an agency determination that regulation is needed, it cantake three and a half years to develop the regulation, then anotheryear or two to allow water utilities time to come into compliancewith testing requirements. Federal regulators must also evaluate cost-effective methods oftreatment. If cyanobacteria get into some types of water filtrationsystems, you can wind up bursting the cells and releasing thetoxins and making it worse, McClelland says. It s much betterto prevent it from happening in the first place than to rely onfiltering it out. While residents who drink lake water can t expect regulatoryprotection anytime soon, Lake Champlain area water utilities willreceive an informational fact sheet regarding cyanobacteria fromthe EPA sometime in May 2013. Row crops and the honey wagon A study for the International Joint Commission, funded by the LakeChamplain Basin Project, is using high-resolution lidartopographical data to identify critical phosphorus source areas inthe land surrounding Mississquoi Bay. The data has revealed largedifferences in rainfall at different points within the MississquoiBay basin, and helped pinpoint individual fields which are thehighest phosphorus contributors. Only a few fields are showing the highest levels of phosphorus, says Julie Moore, a registered professional engineer, formerVermont Agency of Natural Resources employee, and group leader ofwater resources management for Stone Environmental. Agriculturalland contributes 64 percent of the phosphorus load into MississquoiBay, the studies reveal, with farms around Rock River doing thelargest share of damage. Nearly 60 percent of the phosphorus iscontributed by only 10 percent of the land area, with fieldsplanted in corn rotations generating the highest level ofphosphorus. The e-commerce company in China offers quality products such as Metallic Bubble Mailers , Plastic Mailing Envelopes Manufacturer, and more. For more , please visit Bubble Wrap Bags today!
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