Landing Road Beach Closed to Swimming
The beach at Landing Road is closed for swimming effective immediately due to an exceedance in enterococci and geomean.
1. Enterococci
What it is: A type of bacteria.
The limit: In saltwater, a single test sample should not exceed 104 colony-forming units (CFU) per 100 milliliters of water. In freshwater, the limit is stricter (often 61 CFU).
Exceedance: If a sample tests above this limit, it is an exceedance. [1, 2]
2. Geomean (Geometric Mean)
What it is: A special average. Instead of looking at one day, it looks at a rolling average of the last 5 test results.
The limit: In saltwater, the average must stay below 35 CFU per 100 milliliters. In freshwater, it must be below 33 CFU.
Geomean Closed: If the average over the last month climbs too high, the beach is closed until newer, cleaner tests pull the average back down. [1, 2, 3]
Why do these spikes happen?
Stormwater runoff: Heavy rain washes polluted water, pet waste, and bird droppings into the ocean or lake.
High tides: Tide cycles can sometimes concentrate existing bacteria in the water.
Animal activity: Large flocks of birds or dogs on the beach can spike bacteria counts. [1, 2, 3, 4, 5]
How to check current beach status
You can check local beach closures in Massachusetts using the Mass.gov Marine and Freshwater Beaches portal.
https://www.mass.gov/info-details/interactive-beach-water-quality-dashboard