Spofford Lake Water
Quality Test Results for 2011
Attachments:
E.coli & Phosphorus Test Results. Water Quality Metrics '88-'11
E.coli levels, as you can see from the attached table, were very low at
the town’s public and private beaches. The only exception to this was the July reading at Camp Spofford Beach. E. coli levels around Pierce Island
were low as well
At Camp Spofford Inlet and the Clarksdale pipe, E.coli levels
were consistently higher than the swimming limit.
Total Phosphorus concentration is an indicator of
biological nutrient production. Reducing the amount of phosphorus in a lake
will typically result in reduced algal concentrations. According to DES, “Phosphorus sources within
a lake’s watershed include septic system effluent, animal waste, lawn fertilizer, eroding roadways,
construction sites, natural wetlands, and atmospheric deposition”.
At surface levels, total phosphorus levels at Spofford Lake were about the same as 2010. We note that phosphorus levels at the Camp
Spofford inlet and the Clarksdale
pipe were 'greater than desirable' to 'excessive'. At the Hypolimnion or 'Deep Spot' in the middle of the Lake, total phosphorus are also 'greater than desirable'. Phosphorus levels at inlets can be affected by rain and run
off. The Deep Spot is different. Here,
the total phosphorus collects and will, over time, cause the clarity & quality of the Lake to decline.
Phosphorus
in a lake is like mercury in your body… it stays. Higher phosphorus levels,
particularly in the deep parts of the lake, indicate an improving environment
for algae, other phytoplankton and cyanobacteria. In sufficient numbers, these
plants may then produce colored blooms,
toxins and diminished water clarity.
Take a look at the historical data provided below.
