News12 New York
N12 Originals
Numbers & Links
Local
Crime
Weather
NYC Politics
Rebuilding Brooklyn

Harmful algal blooms reported in Rockland County lakes

The DEC urges the public to report sightings and track active blooms through its website.

Diane Caruso

May 29, 2026, 5:00 PM

Updated

Share:

More Stories

Harmful algal blooms have appeared this week in Rockland Lake and Sebago Lake in Rockland County, prompting reminders from state experts about reporting them.

Brian Duffy, of the New York State Department of Environmental Conservation (DEC), described blooms as “Green streaky, spilled paint appearance, pea soup appearance, sometimes chunks, sometimes green globs.”

Duffy said harmful algal blooms, often called HABs, become more common as the weather warms.

“This is when they're ramping up - hot, dry conditions. As temperatures increase, as they're doing now, that's when we see blooms occurring all across the state," Duffy says.

He noted they may be more prevalent during late summer months.

The DEC urges the public to report sightings and track active blooms through its website. While research continues into long‑term mitigation tools, Duffy says there are currently limited options for treating blooms once they appear. Lakes themselves typically remain open, but swimming areas can be closed if blooms are detected.

News 12 couldn't find any blooms at either lake on Friday while people were out enjoying the water.

Experts say high phosphorus levels are a major driver of harmful algal blooms. Jen Zunino‑Smith, of the Cornell Cooperative Extension of Rockland, explained that phosphorus is an emerging contaminant.

"That means we're not hearing a lot about it now, but we will start to hear more and more about it," Zunino‑Smith says.

She noted that everyday activities, such as cutting grass or washing cars, can contribute to phosphorus runoff when materials flow into storm drains. New York state law prohibits the use of fertilizers containing phosphorus unless specific conditions are met.

Anna Hickey, also with the Cornell Cooperative Extension of Rockland, said residents can check fertilizer labels to ensure compliance.

“There's always a ratio on the front of the fertilizer bag and the middle number represents phosphorus, and you want that number to be zero," she says.

The DEC says they have a research grant program to address HAB challenges.

More Stories

Top Stories

00:22
mysterysewermen530pZC_2026-05-29-17-44-44

Group of 7 people mysteriously emerges from sewer in Gravesend

01:41
FB Gust

A chilly and windy start to the weekend for Brooklyn

01:38
Screenshot 2026-05-29 054112

Suspect sought in rape at Kaiser Park

01:16
bikeliferiderssavedriverCM_2026-05-29-17-36-10

Caught on Camera: Bikers rescue unconscious driver, passenger and child in Brooklyn

01:59
bxzooelephantfutureCM_2026-05-29-17-47-53

One elephant left at Bronx Zoo following death of another elephant named 'Happy'

01:16
BKEDRICHITFRI52926_2026-05-29-08-57-56

Man stabbed on Q train in Flatbush as string of violence continues

02:15
MTNJAmtrak330p0529_2026-05-29-15-43-45

NJ Transit service resumes after Amtrak fire that injured 5; residual delays expected

02:02
Screenshot 2026-05-28 175808

Man fatally stabbed in Canarsie among 4 killed in violent week across Brooklyn

APnewstn

Judge temporarily blocks payouts from Trump’s $1.8B ‘anti-weaponization’ settlement fund

01:17
BKCANARSIEFLAKS52926_2026-05-29-05-52-31

Canarsie residents say growing sinkholes on Flatlands Avenue are creating safety hazards

01:33
shotsfiredonbusCM_2026-05-28-22-35-48

Gunfire in East New York sends bullet through MTA Bus; no injuries reported

00:42
parrottplfatalhitandrun1030pZC_2026-05-28-22-41-29

Man struck and killed by van driving in reverse in Dyker Heights hit-and-run

00:16
fultonstfatalstabbingfoloID1030pZC_2026-05-28-22-40-50

Police identify victim of Cypress Hills fatal stabbing

00:32
6thavehomicideID1030pZC_2026-05-28-22-40-35

Man stabbed to death, another slashed in the face in front of Sunset Park supermarket

01:41
acslawsuitCM_2026-05-28-22-12-57

Class action lawsuit accuses ACS of illegally separating families

00:39
2yodeathlottaveCM_2026-05-28-22-24-44

2-year-old baby found dead in Brownsville apartment

02:11
studentshousingconditions10pmCM_2026-05-28-22-08-48

Students, young tenants to speak with Mayor Mamdani at housing hearing

00:49
anthonymirandafiredCM_2026-05-28-22-40-50

Mayor Mamdani terminates NYC Sheriff Anthony Miranda, appoints Edwin Raymond as new sheriff

AP26146074363841

Knicks center Mitchell Robinson has a broken right pinkie finger, AP source says

01:40
merchantsaskforgtrainchange530pZC_2026-05-28-17-55-13

Greenpoint residents fight back against G Train shutdowns

App StoreGoogle Play Store

info

Newsletter

Send Photos/Videos

Contact

About Us

News Team

News 12 New York

follow us

Twitter

Facebook

Instagram

more resources

Optimum Corporate

Optimum Service

Advertise on News 12

Careers

Content Removal Policy

© 2026 N12N, LLC

Privacy Policy

Terms of Service

Ad Choices