Photo: Nagaraju Ramanna
Phosphorus pollution is causing algal blooms in Lake Champlain and the EPA is cracking down on regional emitters. The excess alga threatens the lake’s water quality, encroaches on wildlife habitat and poses a human health risk.
According to the EPA, “When chemical pollutants exceed maximum or fall below minimum allowable concentrations, waters may no longer be able to support the designated uses such as fishing, swimming and drinking.”
In 2002, the state of Vermont set a limit to the Total Maximum Daily Load (TMDL) of phosphorus runoff into the lake. The restriction was supposed to reduce pollution loading such that the lake would pass state water quality criteria. In 2011, the EPA denounced the TMDL standards set in 2002 due to unacceptable nutrient levels in the water.
Last week, the EPA, with input from local partners, set new phosphorus TMDL standards for 12 segments of the lakes 13 subdivisions. “The largest source of phosphorus is the agricultural sector, followed by stream bank erosion, developed land, and forests” (which respectively account for 41 percent, 21 percent, 18 percent and 16 percent of the base load).
The new standards call for a contraction of 213 metric tons per year of phosphorus runoff into the lake. That’s a 34 percent reduction from the annual average of 631 metric tons polluted between 2001 and 2010. The EPA intends to cut the load by calling for a 55 percent curtailment in runoff from the agriculture sector, whereas other sectors will be expected to make lesser reductions.
“While EPA is setting the targets, the strategies for meeting those targets has and will continue to be led by Vermont. Act 64 and the state’s Implementation Plan provide a progressive roadmap for achieving these targets,” said EPA representative, Curt Spalding.
The EPA will monitor state’s efforts and critique progress in a report card by 2018. The environmental watchdog will “take appropriate federal action if Vermont fails to meet the key milestones.”
The agriculture industry – especially animal agriculture – is responsible for the majority of phosphorus pollution in the world. In addition to contaminating freshwater bodies, chemical runoff from agriculture operations causes ocean dead zones in places like the Gulf of Mexico and elsewhere.