Nantucket Water Health Report
Capaum Pond - 2020
This Nantucket Land Council Water Report uses an index to measure the nutrient-related health of island water bodies. It provides a snapshot using monitoring data collected by the Nantucket Land Council and analyzed in a laboratory. Each Water Quality Indicator is assigned a score from 100 to 0, with 100 being pristine water and 0 representing severe nutrient pollution.
Water Quality Indicator
Score
Summary
Transparency
17
Algae in Capaum’s water column was so dense it blocked most light from reaching the bottom. Average visibility was 2.5 feet. Capaum’s max depth: ~8 feet.
Nutrient Concentration
38
High phosphorus concentrations lead to dense phytoplankton (algae) communities, including toxin producing species.
Chlorophyll-a
34
High concentrations of this common plant pigment (a measure of algae abundance) exceed healthy levels for a pond of this size.
Overall Water Quality
30
High phosphorus concentrations drove severe and lengthy harmful algal blooms.
Land-Use Practices for a Healthy Pond Capaum Pond Watershed Homeowners adjacent to Capaum Pond, or within the Capaum Pond watershed can institute these healthy pond practices to reduce nutrient pollution (Phosphorus is most detrimental in freshwater).
Landscaping Practices 1. Eliminate or reduce fertilizer use as much as possible, and never use products containing Phosphorus. 2. Make sure your landscaper is certified by the Town of Nantucket and is following the Best Management Practices (BMPs) for Fertilizer Use on Nantucket. 3. Use slow-release fertilizer, never fertilize before rain, or between October 1st and April 1st. 4. Reduce the size of your lawn and maintain a large native vegetation buffer adjacent to the Pond or its associated wetlands.
Septic System Maintenance 1. Have your septic tank pumped every 1-2 years, or as recommended, to keep it in good working order. 2. Always have your system inspected if you suspect it is not functioning properly. For more information visit: nantucketlandcouncil.org/education/fertilizer-guidelines/ Emily Molden: t (508) 228-2818 Emily@nantucketlandcouncil.org