Mamanasco Lake

Ridgefield, Connecticut · on Mamanasco Lake

Verified · 4 independent sources · top-verified

WATER: lake
ACCESS: Local spot, unofficial
FEE: $150/year
SEASON: Best in summer

About Mamanasco Lake

Mamanasco Lake is a shallow, roughly 86 to 96 acre lake in Ridgefield, Connecticut, dammed in 1716 to power a grist mill. As a lake to swim in it splits two ways: an informal swimming hole off the cliffs at the town's Richardson Park, and members-only swimming at the private Mamanasco Beach Club on the lake's shore; a free state boat launch also sits on the southwest end.

The lake sits in a residential watershed of roughly 440 homes northwest of downtown Ridgefield, near Ridgefield High School. Richardson Park, the town's largest lakefront landholding, runs along North Salem Road with a meadow that gives way to woodland trail leading to a rocky overlook known locally as the Mamanasco Cliffs.

Swimming at Mamanasco Lake

Swimming at Mamanasco Lake is split between two different kinds of access: an informal, unsanctioned spot where local teenagers cliff-jump from roughly 30-foot rock outcrops in Richardson Park into the lake, and supervised swimming for paying members at the private Mamanasco Beach Club, which has a swim area and docks on the shore. The lake itself is shallow (average 5-6 feet, 10-foot maximum in the central basin), so the cliff-jumping spot involves a real mismatch between jump height and water depth.

How to get to this swimming hole

From downtown Ridgefield, take North Salem Road to Richardson Park at 729 North Salem Road; park in the lot on the south side of the road, then follow the meadow/woodland loop trail west to the rocky Mamanasco Cliffs overlook on the lake.

Parking: Parking area off the south side of North Salem Road at 729 North Salem Road (Richardson Park). A separate parking area serves the state-owned boat launch on the lake's southwest end.

The hike in

Richardson Park Loop

To the water: Roughly 0.3 mi one-way (the cliffs sit about halfway around the ~0.6 mi round-trip loop)
Time on foot: About 15-20 minutes for the full loop; the cliffs are reachable in under 10 minutes from the lot

Difficulty: easy - flat meadow and woodland walking, no significant elevation gain

Trailhead: Richardson Park lot off the south side of North Salem Road, 729 North Salem Road, Ridgefield, CT

The Mamanasco Cliffs overlook is reached partway around Richardson Park's own short ~0.6-mile loop trail, not a separate longer trail; the loop starts in the meadow near the parking lot and heads into woodland to the rocky lakeside overlook before circling back.

No stream crossings or scrambling reported; footing at the cliff edge itself is rocky and unmarked, so care is needed right at the jump spot.

Plan your visit

Bringing kids

OK with supervision

The only public swimming access is informal cliff-jumping (~30 ft) at Richardson Park into a lake that averages just 5-6 ft deep (10 ft max in the central basin) with no lifeguard on duty, so it is unsuitable for young or inexperienced kids to jump. Families with young children are better served either by wading/picnicking at Richardson Park's shoreline rather than jumping, or by joining the private, supervised Mamanasco Beach Club, which has a swim area for members.

Parking

Free

Free town parking lot on the south side of North Salem Road at Richardson Park (729 North Salem Road), Ridgefield. A separate free state-maintained parking area serves the boat ramp at the lake's southwest end.

Water clarity

Varies with season and flow

A visitor-guide aggregator describes Mamanasco Lake as having 'clear waters,' but first-hand news reporting (CT Insider) describes recurring algae blooms, invasive weed growth (Eurasian watermilfoil), and decomposed organic matter that the Mamanasco Lake Improvement Fund actively removes. As a shallow (5-6 ft average), eutrophic New England pond, clarity likely swings with season and algae bloom timing rather than staying consistently clear.

Swim smart

Shallow water (5-6 ft average, 10 ft max) beneath the roughly 30-foot cliff-jumping spot at Richardson Park creates a real depth-versus-jump-height risk; the lake also has recurring algae/weed growth from fertilizer runoff and invasive species (Eurasian watermilfoil, zebra mussels) that have required active management by the Mamanasco Lake Improvement Fund.

Rules: Gasoline motors, snowmobiles, and jet skis are prohibited on the lake; only kayaks, canoes, paddleboards, rowboats, electric-motor boats, and sailboats are permitted. Connecticut law requires boats be thoroughly washed and dried before launching to prevent spreading invasive species.

This is an informational listing, not an invitation. Conditions and access change; verify locally before you go. Visiting any swimming hole is at your own risk. See our Terms of Use.

On the water

KayaksCanoesPaddleboardsSailboatsElectric_motor_boatRowboats

Restrictions: Gasoline motors, snowmobiles, and jet skis are prohibited lake-wide; only human-powered craft, sailboats, and electric-motor boats are allowed. Connecticut law also requires boats be washed and fully dried before launching to prevent spreading invasive species (this lake has an active watermilfoil problem).

Carry-in access is via the free state boat ramp at the lake's southwest end (open to the public) or via the private Mamanasco Beach Club docks (members only).

Backstory

The lake was created in 1716 when settlers dammed a natural waterway to power a grist mill, expanding it to roughly three times its original size; ruins of a 19th-century paper mill are still visible off Pond Road. The Mamanasco Lake Improvement Fund, founded in 1971 by Herb Camp, manages algae, invasive weeds, and organic sediment buildup in the lake.

Mamanasco Lake: FAQ

Does Mamanasco Lake charge a fee?

Richardson Park and the state boat launch are free and open to the public. The separate Mamanasco Beach Club is a private membership club, not open to the general public: $150/year individual, $250/year family, $75/year senior.

Is Mamanasco Lake kid friendly?

How hard is the hike to Mamanasco Lake?

A hike is required, about Roughly 0.3 mi one-way (the cliffs sit about halfway around the ~0.6 mi round-trip loop) to the water (about 15-20 minutes for the full loop; the cliffs are reachable in under 10 minutes from the lot). Wear real shoes, since approaches to natural swim spots are often rocky or rooty.

Where do I park for Mamanasco Lake?

Can I bring a kayak or paddleboard to Mamanasco Lake?

Carry-in access is via the free state boat ramp at the lake's southwest end (open to the public) or via the private Mamanasco Beach Club docks (members only).

When is the best time to visit Mamanasco Lake?

Warmer months (summer) for swimming and boating; the lake is also used for ice fishing and historically ice skating in winter.

What are the rules at Mamanasco Lake?

Gasoline motors, snowmobiles, and jet skis are prohibited on the lake; only kayaks, canoes, paddleboards, rowboats, electric-motor boats, and sailboats are permitted. Connecticut law requires boats be thoroughly washed and dried before launching to prevent spreading invasive species.

What water body is Mamanasco Lake on?

Mamanasco Lake is on Mamanasco Lake, a natural lake verified in USGS hydrography data.