Worden Pond's First Hydrilla Treatment Is Slow on Purpose

Worden Pond's first hydrilla treatment ever started on August 7, 2026. If you've been out on the water since then, you probably haven't seen any change. That's how the treatment is designed. The herbicide being used works over months and years. So this fall, the most important changes at Rhode Island's largest natural lake are at the boat ramp on Worden's Pond Road, and they're about what boats carry out of the pond.

The size of the problem explains the approach.

A Quarter of the Pond, and Denser Than Two Years Ago

RIDEM first documented hydrilla at Worden Pond in November 2023, after staff saw the plant washing up onto the ramp. It's an aggressive invasive that the federal government classifies as a noxious weed. RIDEM had a baseline survey done in June 2024 and a pre-treatment survey in July 2026. Comparing the two shows how fast it has spread.

In two years, the infested area grew by about 76 acres, and the thickest growth went from none to roughly a third of the total. The Town of South Kingstown puts the infestation at about 224 acres, which is nearly one-quarter of Worden's 1,098 acres. According to the July 2026 report, the largest continuous bed is in the southeastern part of the pond. Growth is also heavy on the western side, with scattered patches to the north, northwest, and south-central areas.

The report doesn't treat the spread as surprising. It says the expansion "is not unexpected, as management of hydrilla in Worden Pond has not been possible to date." Until August, nobody had treated the pond at all.

Why the Treatment Won't Show This Season

RIDEM chose The Pond and Lake Connection for the whole-lake treatment, which is being paid for with Congressionally Directed Spending through the U.S. Department of Agriculture. Senators Jack Reed and Sheldon Whitehouse secured the money. Reed said the work is backed by "up to $500,000 in federal funding."

The herbicide is fluridone, applied at low doses. According to the town, the low dose targets hydrilla while limiting harm to sensitive native plants. Fluridone works slowly. It's absorbed through the whole plant and blocks photosynthesis, so it only works if the concentration stays high enough for long enough. That's why applications keep coming through November. The town's notice says it plainly: "Residents and visitors may not notice immediate changes following an application."

Here's what that means if you use the pond:

• Boating, swimming, and fishing are not restricted. Both RIDEM and the town say the treatment won't harm fish or wildlife.
• Irrigation may be restricted for a short time. The town's August 2026 newsletter said temporary limits on irrigation may apply right after a treatment.
• Application dates arrive by email. You can sign up through the town for notices of future treatments. Write "Worden Pond" on line 4 of the registration form linked in the town's notice.
• This is a multi-year effort. Because the infestation is so large and severe, the town expects control to take "several years of successive treatments," with federal funding expected to cover more than one year.

When a slow herbicide is working on a pond that's a quarter infested, the people using it have to do their part in the meantime. Their part is keeping fragments from spreading, and that starts at the ramp.

The Buoys Are About What Leaves the Pond

Hydrilla spreads from small pieces. When a propeller cuts through a bed, the fragments can stay alive, drift, and take root somewhere else. On September 11, 2026, the town announced a new buoy-marked boating lane near the Worden Pond Boat Ramp. It guides motorboats through the smallest part of the pond's largest known hydrilla patch and out to more open water. Boaters are asked to stay in the lane coming in and going out.

The town names two goals. The first is fewer fragments chopped loose by passing boats. The second, which matters to anyone running an outboard, may be fewer stops to clear weeds off the motor.

The buoys came from local volunteers. The Wood-Pawcatuck Wild and Scenic Rivers Stewardship Council bought them with a Southeast New England Program mini-grant from Restore America's Estuaries, and its volunteers led the project. RIDEM's Division of Fish and Wildlife installed the buoys, with guidance and permitting from the RIDEM Office of Water Resources.

Hydrilla also grows right next to the launch. The July 2026 survey recorded a sparse patch of about 3.8 acres beside the Worden Pond boat launch. And boats regularly carry plants out. This summer, DEM boat greeters at the ramp reminded more than 200 boaters to clean their boats. Their data showed that about 17% of boats leaving the pond had plants attached.

The ramp has equipment for this. In May 2025, the town installed a free, self-service boat-cleaning station at the Worden ramp, open during boating season. It was paid for with $35,000 from an EPA Section 319 grant and $21,610 from South Kingstown. The guidance is to clean, drain, and dry boats and gear for at least 24 hours, or wipe them down, before using them anywhere else. Rhode Island law prohibits moving any type of plant on boats, vehicles, trailers, or gear.

These pieces fit together. The lane cuts down on fragments created on the water, and the cleaning station catches fragments before they leave on a trailer. According to the town, the lane and the herbicide together should reduce the number of live fragments in Worden. They should also lower the risk that boats and equipment carry hydrilla to other lakes and reservoirs in Rhode Island.

Using the Pond Between Now and the Next Survey

RIDEM lists the state ramp on Worden's Pond Road, with a cement ramp, parking, and no horsepower restriction listed. The July 2026 survey report places the launch at the pond's southern end and notes its dock. To the northwest, the pond borders the Great Swamp Management Area. The Chipuxet River flows in from the north, and the Pawcatuck flows out to the west.

For paddlers, the Wood-Pawcatuck Watershed Association's paddling maps describe a route of about eight miles. It starts at Taylor's Landing, a DEM access on the Chipuxet upstream of the pond, and ends at Biscuit City. The association rates it intermediate to advanced. The route includes a winding marsh section, likely portages, and an exposed crossing of the pond that runs 1.5 to 2 miles. The maps were last updated in 2020, so conditions along the route may have changed since then.

If you spend fall weekends around the Great Swamp, keep the hunting calendar in mind. South Kingstown is in deer hunting Zone 1. Under Rhode Island's hunting regulations, archery season runs from September 15 to January 31. Applying the regulation's dates to the 2026 calendar puts muzzleloader season at November 7 through December 4 and shotgun season at December 5 through 31. RIDEM is also holding two muzzleloader "Learn to Shoot" sessions at 277 Great Neck Road in West Kingston on October 27 and 29, so expect activity at that address on those afternoons.

On water quality, the most recent Worden-specific notice from the Rhode Island Department of Health is more than a year old. In June 2025, health and environmental officials advised people to avoid the pond because of a harmful algal bloom. They lifted the advisory on June 26, 2025, after testing found low algae levels and no toxins. That doesn't tell you anything about conditions this fall. Check the state's current advisories before a swim or a paddle with the dog.

What Arrives by December

So far, the first season of treatment has been invisible. The first measurement of whether it worked is coming soon. The July 2026 report called for a post-treatment survey in September and an annual report due by December 1, 2026. When that report comes out, it should show whether 225 acres is the peak or just another step up from 148. Until then, the parts of this effort you can see are at the south end of the pond: the buoys from the ramp out to open water, the cleaning station, and the boat greeters' 17% figure.

If you own a home on or near Worden Pond, the treatment schedule and the coming survey results are likely to affect how you plan your seasons, and possibly when a sale or purchase makes sense. Fran Bidell follows these South Kingstown details closely. She's happy to talk through what the December report means for your corner of the pond. Let's Connect.

This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.