13th annual Riverkeeper Sweep: May the Fourth was with us!

By Volunteer and Outreach Coordinator Katie Leung and Sweep Assistant Claudia Mausner

Sweep cleanup volunteers

During the 13th Annual Riverkeeper Sweep on May 4, more than 2,000 volunteers participated in the Hudson River’s largest annual shoreline cleanup. Together, in just one day, we achieved incredible results:

147 tires removed
1465 native trees, shrubs, and flowers planted or maintained
2053 volunteers
122 projects
23 tons of debris cleaned up

The 23-ton grand total includes 1,301 bags of trash, 1.2 tons of recycling, and 1.5 tons of tires. Other large debris removed by volunteers included construction materials, scrap metal, car bumpers, Styrofoam blocks, a sofa, a shopping cart, fuel containers, a bed frame, and a mattress and chairs.

Take a look at some highlights from along the river.

This effort is made possible by our Sweep Leaders, volunteers, sponsors, local communities, corporate volunteers, and brewery and other partners including municipalities and nonprofits. It’s inspiring to see local organizations, schools, scout troops, religious communities, and many others team up to achieve visible, lasting results.

All ages were represented among the 2,050 volunteers that participated in Riverkeeper’s 13th annual Sweep. Parents arrived with infants in shoulder carriers; at least 250 elementary-age children and teens participated with their families, schools, and Scout troops; and over 1,700 adults, including several energetic volunteers in their 80s and 90s, gave it their all to pick up every single piece of trash they found.

Though the amount of trash we continue to find on our shorelines remains formidable, many of our Sweep project leaders report that it is gradually decreasing over the years. In a few locations Sweep leaders have even involved local fishermen to partake in the cleanup activities. These annual cleanups appear to be having a cumulative effect on the amount of trash in and around the Hudson and its tributaries – and the care and attention of local volunteers is leading to greater efforts by the wider community to minimize litter.

What’s in Hudson River trash?

Single-use plastics, including food packaging and bottles, make up the bulk of the trash gathered at Sweep projects. Riverkeeper has helped pass legislation to reduce the volume of single-use plastic and micro-debris in the environment, such as the 2015 Federal Microbeads Free Waters Act, the 2019 New York City bill restricting the sale or use of certain polystyrene items, and the 2020 New York State Bag Waste Reduction Law. Reduction in single-use plastic bag litter has been notable since passage of the 2020 legislation. But clearly we have more to do.

Beginning last year, we asked volunteers to estimate the percentage of plastics found from all the trash they collected and to note product brands on items found during their cleanups. We will continue to review this information in future Sweeps to look for patterns. This year, the Sweep sites estimated that 54 percent of the collected trash was plastics. Out of 81 types of litter identifiable by brand labels, Sweep participants found the highest number from Poland Spring, Coca-Cola, and Dunkin Donuts, followed by McDonalds, Gatorade, and Corona (see below):

A figure of the most found brands during cleanup

In 2024, plastic bottles remained the most common type of trash found at the project locations. Other common items included aluminum cans, Styrofoam, cigarette butts, small pieces of glass and plastic, and food wrappers.

Among this year’s surprises were a machete and fishing knives; bags of fish; spent gun shell casings; a VHS tape of “My Cousin Vinny” (in perfect condition); dolls including Barbie, a baby doll leg, and a broken GI Joe; mannequin legs; a playground set; a wheelbarrow; Tyke bikes; lottery and parking tickets; a metal safe; a set of house keys; a picnic table umbrella; and Halloween costumes including a plastic “bloody” tooth, which – as it happens – a dental student found!

Amount of waste by county

It’s no surprise that Sweep volunteers in the five boroughs of New York City collected the most trash by weight. While Dutchess County had more project sites than Orange, Ulster, and Columbia, less trash was collected comparatively. Additionally, Dutchess sites hosted a total of 224 volunteers, whereas Orange sites hosted 234 volunteers and Ulster sites hosted 181. Of the four counties, Columbia sites had the fewest volunteers (83), but accumulated the most trash.

A graph of the amount of waste by county in pounds

What we’ve achieved in a decade

Sweep projects can vary considerably. In some, volunteers gather debris by land or by water, often using kayaks and small watercraft. In others, volunteers participate in ecological restoration by planting trees, removing invasive species, or restoring street ends where urban waterways meet the pavement. Over the course of 13 years, Riverkeeper Sweep has organized 1,321 projects and almost 24,000 volunteers who have collectively removed 378 tons of debris, including 36 tons of recycling and 2,236 tires. Volunteers have planted or maintained over 8,595 native trees, shrubs, and flowers, and removed thousands of pounds of invasive species.

A graph of the locations and volunteers by year

Sweep as ecological restoration

With many sites becoming cleaner over time and with successive Sweep events, some projects have shifted their focus from trash cleanup to ecological restoration: maintenance and planting of trees, shrubs, and plants as well as removal of invasive species. This year, more than a dozen Sweep sites participated in restoration activities and three sites worked with the New York State Department of Environmental Conservation’s “Trees for Tribs” program. Volunteers planted almost 1,400 trees and shrubs, and they maintained 67 more by pruning and/or spreading topsoil and mulch. These species included shadbush, witch hazel, ninebark, dogwood, milkweed, buttonbush, elderberry, red oak, hybrid poplar, white spruce, and willow. Volunteers also removed more than 1,600 pounds of invasive plant species, including mugwort, water chestnut seeds, multiflora rose, knotweed, tree of heaven, sumac, locust, bittersweet, and creeping myrtle.

As more trash is removed from the shoreline and other natural spaces, there is more light and space for native plantlife to flourish. Not only does this contribute to a healthier ecosystem, but it also helps protect surrounding properties from flooding during heavy rainstorms.

Comprehensive Data Collection Initiative

Sweep’s Comprehensive Data Collection Initiative (CDCI), which identifies and records every single piece of trash collected at a site, was in full swing this year, with 25 of the Sweep sites participating (more than double the number from last year).

Detailed data gathered with CDCI offers insights into how much and what kind of waste enters the Hudson. During this year’s Sweep, volunteers at the 25 sites carefully tallied all the trash collected, using a worksheet adapted from the Ocean Conservancy. Here are the top 10 items found at these sites:

A graph of the most commonly found items

Fishing/boating debris in the river

In the 56 years since Riverkeeper’s founding, the Hudson River’s water has become cleaner and safer for recreational boating and fishing. Although we are proud that the river is so well used, the large amount of fishing and boating waste gathered during Sweep reflects the need for more care and concern. Roughly 30 percent of the CDCI sites found styrofoam buoys from boats and docks, pieces of rope or fishing line one yard or longer, worm containers, the occasional fishing rod, fishing hooks, and bags of dead fish. Some Sweep leaders have formed informal partnerships with groups of local fishermen, who participated in their own cleanup activities.

Microplastic madness

This year plastic and foam pieces topped the chart at CDCI sites along with cigarette butts, food wrappers, and plastic bottles and caps. Micro-trash was particularly prominent at CDCI sites, with plastic, foam, and glass pieces under 2.5 cm in diameter all within the top 10 items collected. Marine animals often mistake these small bits for food, harming the animal and introducing plastic into the food web.

CDCI volunteers collected more than 3,400 cigarette butts this year. Though cigarette butt litter is the most “accepted” form of litter worldwide, it has become a major source of environmental pollution. The nicotine filters of cigarette butts are made of a type of plastic called cellulose acetate, which is not biodegradable and releases toxic chemicals, heavy metals, and microplastics when it breaks down. The Tobacco Product Waste Reduction Act has been introduced in the New York State Assembly several times, but has yet to gain traction.

Bottles, bottles everywhere

Although plastic bottles and caps didn’t top the list of the most frequently counted items for CDCI this year, they were still the most common item overall. Volunteers across 122 sites collected more than 5,000 plastic bottles from the Hudson and its tributaries. Continuing last year’s trend, our 2024 Sweep volunteers also noted a decline in the number of plastic bags found, and many bags were degraded or shredded. Volunteers believe it’s possible that many plastic bags have been moving through the river system for a number of years, having been tossed prior to passage of New York’s Bag Waste Reduction Act in 2020. If we have a new opportunity to push it through, the Bigger Better Bottle Bill will do for plastic bottles what the Waste Reduction Act has done for plastic bags. In the meantime, Riverkeeper will continue organizing its Sweep, helping communities protect the river they rely on and cherish.