Saylorville Lake has one swimming beach and it's at Oak Grove Recreation Area. The beach has a vault restroom, a foot wash area, a large parking lot and a life jacket loaner station with four different sizes available - adult, child, youth and infant.
There's a very large sandy area between the parking lot and swimming area. One side has two sand volleyball courts. The swimming area is a 1/4 mile long, so there's plenty of space to spread out even when it's crowded.
Overall, we really like the beach at Oak Grove but there are some elements that make it not very kid-friendly. The beach is very popular with college students who like to drink and blast loud music with explicit lyrics. I just wish they'd drink out of cans instead of bottles because I find broken glass in the sand each visit.
2024 Update - The beach is currently closed due to high water. You can check the Status of Recreation Facilities list to confirm when the beach is open.