Beltzville State Park Beach is a 525 foot strip of sand on the north shore of Beltzville Lake, five miles east of Lehighton in Carbon County, off U.S. Route 209. It sits at the bottom of the day use area below Parking Lots A and B, with the Pine Run arm of the lake curling in just east of it, and it is the only sanctioned swimming spot on a 949 acre reservoir with roughly 20 miles of shoreline. On a hot Saturday in July it fills.

The water is reservoir water, not spring water. It warms well by late June and stays warm into early September, and it carries the green tint and limited visibility that go with an impoundment on a Pennsylvania creek. Entry is gentle. A paved ramp runs from the parking lot across the sand and continues into the water, which makes this one of the few state park beaches you can get a beach wheelchair or a stroller into without a fight. The graded sand runs out a short way before it gives over to the lake bed of silt and gravel. Swimming is confined to the buoy line, and past the buoys the bottom drops off into a boating lake with a 45 mph limit, so the rope is a real boundary.

None of this existed before 1971. The Army Corps of Engineers closed Beltzville Dam across the Pohopoco Creek valley on September 17 of that year, an embankment 4,300 feet long standing 170 feet above the old creek bed, one of five flood control structures built for the Lehigh and Delaware basins. The village of Big Creek Valley was vacated in 1966 to make room for the pool, and the park opened in 1972. The Corps still owns the dam; DCNR runs what sits on top of it.

There are no lifeguards. Beltzville runs under the DCNR open swim policy, meaning you swim at your own risk with park staff patrolling rather than guarding. Only Presque Isle and Fuller Lake still keep guards. The beach is open late May through Labor Day, 8 a.m. to sunset, and the surrounding day use area runs 8 a.m. to 8 p.m. in that stretch and 8 a.m. to dusk the rest of the year. A bathhouse with showers stands near the sand, and a food concession works daily through the summer when the weather holds. Smoking is banned on the beach and in the swimming area, and dogs are not allowed in the swimming area at all. Entry costs nothing, since Pennsylvania charges no admission or day use fee at any of its state parks.

The thing worth checking before you drive out is the bacteria posting. Beltzville has been closed to swimming repeatedly in recent seasons on elevated bacteria samples, with resident geese usually named as the cause, and DCNR has to resample before it reopens. Those closures have landed in late May and in midsummer both. Drought years also pull the pool down and widen the flat in front of the sand. The park office is 610-377-0045.

When the beach is shut or crowded, the rest of the park absorbs it. Fifteen miles of trail leave from the same lots, including the one mile Falls Trail loop up to Wild Creek Falls and the two mile Sawmill Loop past a grist mill raceway, several small dams and a slate quarry worked in the 18th and 19th centuries. Pine Run East and Preachers Camp both launch boats, Preachers Camp has an accessible kayak launch, and a seasonal concession rents kayaks, paddleboards and paddleboats.