“Rust Tide” in local waters poses no risk to public health or shellfish closures, says RI DEM
The conversation about portions of Newport Harbor being discolored and smelly started two days ago when Mike Cullen, a resident in the Point Neighborhood, posted on NextDoor;
“Brown, varnish-smelling water strongest @ Elm St Pier but is visibly brown to at least 25 yards off shore up to Battery Park. Source of pollution unknown. A Elm Street swimmer said his eyes hurt. Harbormaster boat seen leaving Elm Street Pier. I notified DEM.”
Newport City Councilor’s Kate Leonard and Justin Mclaughlin were among the 30 to comment on the issue before Representative Lauren Carson (D – District 75, Newport) chimed in on Wednesday;
I did meet today with DEM about the orange/rust in the water and to confirm what Justin has committed, yes, it is a “rust tide.” No public health is at risk. It is a large bloom of naturally occurring phytoplankton causing the water to turn a rust color. The odor is the result of the decay process of the bloom – This is not red tide, and it is expected to decline as water temperatures fall to 60 degrees to lower.
Rust tides have been observed n New York, Long Island, Buzzard’s Bay and Martha’s Vineyard. DEM plans on continuing to monitor the bloom.
The Rhode Island Department of Environmental Management (DEM) has observed and received the reports of rust-colored patches of water (known as “rust tide”) in Narragansett Bay, Mt. Hope Bay and coastal salt ponds.
DEM says “Rust Tide”, not to be confused with Red Tide, poses no public health risk and will not lead to shellfish closures. It is expected to decline as water temperatures fall to 60°F or lower.
Recent water sampling reveals the rust tide is being caused by a large bloom of naturally-occurring phytoplankton called Cochlodinium polykrikoides. This organism contains red photosynthetic pigments which cause the rust color visible on the water surface. Rust tide is not harmful to humans; however, Cochlodinium can damage delicate finfish and shellfish exposed to concentrated populations. Rust tide is not associated with the red tide that caused shellfish closures in other New England states.
Accumulations or blooms of Cochlodinium appear to be a regional phenomenon this summer. Rust tide has been observed in Peconic Bay in New York off the eastern end of Long Island, in Buzzards Bay, and off Martha’s Vineyard in Massachusetts. DEM will continue to monitor the bloom over the next several weeks.
For more information on DEM programs and initiatives, visit www.dem.ri.gov.