Lake Alvin is a 105-acre lake located near Harrisburg, South Dakota, with a maximum depth of 21 feet and an average depth of 9 feet. The lake was created in 1954 by damming Nine Mile Creek and was named in honor of Alvin Dempewolf, the only World War soldier from Harrisburg who died overseas.

This calm, tree-lined lake is designated as a no-wake zone, with a 5 mph speed limit for all watercraft to protect the shoreline from erosion. The 59-acre recreation area offers multiple access points for paddlers, including a swimming beach and boat ramps. A fishing pier and picnic tables are available for breaks during paddling excursions.

The lake provides opportunities to observe various wildlife, including waterfowl and perching birds. Anglers frequently encounter walleye, northern pike, crappie, sunfish, perch, catfish, and bullheads, indicating a healthy aquatic ecosystem that paddlers can appreciate.

The surrounding landscape features a mix of pines and prairie, creating scenic views for paddlers. Multiple trails lead to the shoreline, facilitating easy kayak and canoe carry-in access. The lake's relatively small size and protected status make it particularly suitable for beginners and those seeking a peaceful paddling experience.

Lake Alvin Recreation Area requires an entrance fee, with both daily and annual passes available. The park is open year-round, though facilities such as showers and flush toilets may be closed between October 1 and April 30. Vault toilets typically remain accessible throughout the year.

Note: As of 2024-2025, the beach and boat ramps are undergoing renovations, with closures expected until spring 2025. Paddlers should check current access conditions before visiting during this period.