Lexington sits on the Lake Huron shore in Sanilac County, about 25 miles north of Port Huron on M-25, and the swim beach there belongs to the village rather than to the state. The sand is at Patrick Tierney Memorial Park, usually just called Tierney Park, and it runs north from the root of the harbor breakwall. That distinction matters, because the waterfront facilities here stack up tight against each other and are run by different bodies. Lexington State Harbor, immediately south, is a Michigan DNR marina. The long stone arm reaching out into the lake is a US Army Corps of Engineers breakwall. The beach and the lawn behind it are the Village of Lexington's, and the village charges nothing to walk onto them.

The water access point is at roughly 43.27005, -82.52395, right where the sand meets the breakwall. From there the beach runs several hundred yards north along an open shore with nothing to break the swell. The bottom is sand and stays shallow a good distance out, which is what makes it work for kids, but it also means the whole shelf gets stirred up in an east wind and the water turns brown and choppy fast. The south end, tucked in against the breakwall, is the calmest water on the beach. Farther north the shoreline gives way to cobble and flat limestone slabs below a wooded bluff.

Fees are simple at the beach and less simple next door. The village does not charge admission and does not charge for beach parking. The DNR does charge at the Boynton Street boat launch, and a Michigan Recreation Passport is required for vehicle entry at designated state boating access sites. That passport runs $15 a year for Michigan residents bought at license plate renewal as of 2026, and it is billed separately from harbor slip reservations. None of it applies if you are only going swimming.

There is no lifeguard. Nobody watches this beach and swimming is at your own risk, which is the norm at Michigan public beaches.

Water quality is monitored here, and it has failed before. The Sanilac County Health Department samples county beaches weekly from Memorial Day through Labor Day and posts the results on Thursdays. On June 29, 2023 the department closed Lexington Beach at Tierney Park after a sample averaged 562 E. coli colonies per 100 ml against a state safe swimming limit of 300. Results feed the state BeachGuard system, now part of EGLE's MiEnviro portal, and it is worth a look after heavy rain before you get in.

The park itself closed in September 2025 for a full rebuild and reopened on July 2, 2026 with a new restroom and concession building, an amphitheater, a shoreline boardwalk and more parking. The sand volleyball court, playground, swings and picnic tables are back. The Lexington Arts Council puts on free Friday night concerts in the park through the summer. The harbor next door is another story. The DNR and the Corps have the marina closed from September 2026 through late May 2027 to replace in-water structures, with dredging planned for summer 2027, so expect construction equipment and noise at the south end of the beach.