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This is a call for action against Cladophora: the slimy, messy, stinking, bacteria laden green mess on our beaches. It is necessary to deprive these algae of their major growth-determining nutrient: Phosphate. A little history: The algae have been a nuisance here before, in the 1960's, when laundry and everything else was cleaned with phosphate detergents. Then TSP was banned and phosphate removed from laundry detergents and the algae receded. Levels of reactive phosphorus in the bay of Green Bay fell from an average of 210 ppb in the 1970's to an average of 150 ppb in the 1980's and early1990's with a goal set at 90 ppb. At that time everybody stopped checking except the Little Sturgeon Property Owners who recorded readings in the 400-500 ppb range in 2001 and occasional readings over 1000 ppb in the following years until 2006 when the values stayed consistently at or above 1500 ppb. Spot checks along the bay and lake shores of Door County during April of this year indicate phosphorus levels from 1700 to 5000 ppb. What are the causes? Humans in the Great Lakes Basin continue to flush phosphate into the lakes. The Environmental Protection Agency attributes most of the phosphate load to "non-point" sources, runoff from farmland, lawns and failing septic systems. Sewage treatment plants employ dilution and expensive "tertiary" treatment with aluminum or iron salts to reduce phosphate content of the outflow to an acceptable concentration, but the amount of discharged phosphate remains significant. The main household sources of phosphate are lawn fertilizer and the detergents formulated for automatic dish washers (containing up to 8% phosphate). In both applications the use of phosphate is unnecessary. What is being done? Farmers are introducing "nutrient management" (mandatory in 2008) which determines the selection of fertilizers based on soil tests. In Door County they find that generous concentrations of phosphate are present even in fields that have not received any manure for many years. Concerning lawn fertilizers there is legislation pending in Madison and supported by the Door County Board which would severely limit the use, similar to laws in the State of Minnesota and in Dane County, WI. Washington State has a law limiting the phosphate content in dish detergents to less than 0.5%. By its nature the legislative and regulatory process is slow and unreliable.
1. Use only lawn fertilizer which is free of phosphate. The "middle number" of the fertilizer formula must be zero. Examples: 15-0-5 or 20-0-6. 2. In your dishwasher use only detergent that is free of phosphate. Several brands are available in local markets. They perform as well or better than the most popular phosphate containing brands. In some markets they are displayed in a separate ecological and/or organic product section. DPO in cooperation with neighborhood associations will initiate a schedule to measure and publish phosphate concentration at up to 25 beach and stream locations and in the shore currents of the bay. This information should help to measure progress and to identify phosphate sources. If we can stop new phosphate getting into the lake we hope that the current excess phosphorus will be tied up in the sediments of the deeper sections of the lake. For questions or to volunteer with monitoring contact: EMAIL: Info@DCPhosphateFree.org |
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We are a voluntary coalition
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Hence the DPO call for citizen action: 
