Kelly Warm Spring

What to expect

Kelly Warm Spring is a broad, shallow pond in a grassy meadow beside the Gros Ventre Road, about a mile northeast of the small community of Kelly in the southern part of Grand Teton National Park. Water seeps up from below and keeps the pond at about 80°F27°C all year. It is not a hot spring, although it often turns up online as “Kelly Hot Springs.”

What you will see is a pale green pool fringed with algae mats, an outflow channel heading toward Ditch Creek, and on a clear day a big view of the Teton Range across Antelope Flats. There is a restroom and some interpretive signs. On cold mornings the water steams. In spring, bison and elk often linger here because the grass around the warm water turns green before the rest of the valley.

Tourism pages still describe it as a summer soaking spot. The National Park Service does not. Its place page says entering the warm spring is not recommended and warns that the pool has high levels of E. coli and the presence of Naegleria fowleri, an amoeba that can cause a fatal brain infection if water gets up your nose. We list it so you know what you are driving to, not as a place to swim.

Is swimming allowed?

Plan on no. Two things point the same way:

• The NPS warning. The Grand Teton place page for Kelly Warm Spring advises against entering and names E. coli and Naegleria fowleri.
• The park rule. Grand Teton’s Superintendent’s Compendium, signed in January 2026, says that in the park and the Rockefeller Parkway, swimming in, bathing in or entering a natural thermal pool or stream whose water comes entirely from a thermal spring is prohibited. Kelly Warm Spring is a spring-fed pond, so the rule appears to cover it. Soaking is allowed only in overflow or runoff water that mixes with other streams.

If you need a firm answer for a specific plan, call Grand Teton visitor information at 307-739-3399.

The aquarium fish problem

Kelly Warm Spring has been a dumping ground for unwanted pet fish for decades. Biologists have found swordtails, convict cichlids, guppies, goldfish and tadpole madtoms, along with American bullfrogs. The warm water lets these tropical species survive the Wyoming winter, and some moved down Savage Ditch and Ditch Creek to within 10 yards of the Snake River. They eat the eggs and young of native fish such as Snake River cutthroat trout, suckers, chubs, shiners and dace, compete for food, and spread disease.

After a public comment process that began in 2015, the park treated the spring and its outflow with rotenone, a fish pesticide that breaks down quickly in sunlight, in late August 2018. The treated areas were closed and signed during the work. NPS says 600 to 700 pounds of fish died, but some invasive species survived, and the park is looking at other methods before it restocks native fish. Releasing fish or any other animal into the spring is illegal.

Getting there

From Jackson, drive north on US-191 to Gros Ventre Junction and turn right (east) onto the Gros Ventre Road. Follow it past Gros Ventre Campground and through the village of Kelly. The spring is beside the road about a mile northeast of Kelly, with a small parking area. Everything is paved and the pond is a few steps from the car.

You are inside Grand Teton National Park, so carry a park pass. Standard 7-day passes cost $20 to $35 in 2026 depending on whether you arrive by car, motorcycle or on foot, and non-US residents 16 and over pay an extra $100 unless they hold an annual pass.

When to go

The meadow is worth a stop at any time of year. Spring brings bison and elk to the early grass. Summer is the busiest time, with families picnicking on the lawn. Fall mornings are cold enough for steam off the water. During the Jackson elk reduction program, normally between October and December, a quarter-mile strip along the north side of the Gros Ventre-Kelly Road from Mormon Row Road east to Kelly is closed to public entry, so stay near the road and the parking areas then.

Rules and etiquette

• Stay out of the water. NPS advises against it, and the park rule on spring-fed thermal pools appears to apply.
• Release nothing. No fish, frogs, plants or bait buckets.
• Pets must be leashed and stay within 30 feet of roads and parking areas.
• Give wildlife room. Bison and elk use this meadow; keep at least 25 yards from them, and much more from any bear.
• Pack out trash. Use the restroom at the site.

Where to stay nearby

There is no camping at the spring. Gros Ventre Campground, a large NPS campground on the Gros Ventre River, is on the road between US-191 and Kelly. Jackson has the full range of hotels and motels. For a legal soak with a place to sleep nearby, Astoria Hot Springs Park south of Jackson and Granite Hot Springs Pool on the Bridger-Teton both have campgrounds close by.

Safety notes

• Bacteria and amoeba: NPS reports high E. coli levels and Naegleria fowleri in the pool. Do not wade, swim or let children or dogs drink the water.
• Wildlife: Bison look calm and are not. Watch from the car or the parking area when they are close.
• Soft ground: The edges of the pond are boggy and covered in algae. Stay on firm ground.

Nearby stops worth adding

Mormon Row, with its old barns and Teton views, is a short drive north and west. Farther east on the Gros Ventre Road, the Gros Ventre Slide marks the 1925 landslide that dammed the river and formed Lower Slide Lake. Two years later the natural dam failed, flooded Kelly and killed six people, and only two buildings in town were left standing.