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Big Blue - Mason City IA

Big Blue is a shore accessible fresh water dive site, located in Mason City, IA. This dive site has an average rating of 2.33 out of 5 from 3 scuba divers. The maximum depth is 31-35ft/9-11m. The average visibility is 5-10ft/2-3m.

"Big Blue" is a small water filled clay pit popular with divers. Access is easy, diving is easy, but the visibility is just ok, (but good for Iowa standards) and the water at 35’ is warm. A great "get wet" location and fun due to the number of divers you may meet on a weekend. Mason City is only couple hour drive from Cedar Rapids and 4 lane all the way via the Avenue of the Saints so a day trip works out well. Part of Lester Milligan Park, facilities include a shelter house with electricity, water and restrooms. Also swimming and playground equipment for the kids.

In the hometown of "Music Man" composer Meredith Willson is a quarry called "Big Blue," a 14-acre lake formed after the Mason City Brick and Tile ceased operations sometime in the late ’60s or early ’70s. Big Blue is in the southwest part of town in Lester Milligan Park. The swimming beach is the best spot to enter the water, says Mark Suby, Mason City’s superintendent of parks. Gas-powered motors are not permitted on boats. Local emergency personnel frequently use the lake for training. Underwater is a training platform in 13 feet of depth, old cars and trucks on the lake’s east side, and a 25-foot sailboat. At its narrowest point the Big Blue is 750 feet (227 m) wide.

Depths: 34 feet (10 m)

Visibility: from 5 feet in the spring to 50 feet in the winter, according to one diver.

Water temperature: 70-76 degrees Fahrenheit (21-24 degrees Celsius) in the summer, and 45-70 F (7-21 C) in the spring.

Aquatic life: Largemouth bass, crappie, bluegill, northern pike, and twice each year the lake is stocked with trout.

Fees: None

On-site amenities: Shelter house with electricity, water and restrooms, swimming and playground equipment for the kids.

More info: Call the Mason City Parks and Recreation Department at (641) 421-3673. For other information, call the Mason City Convention & Visitors Bureau at (800) 423-5724.

Open: 6 a.m. to 11 p.m. daily


DiverDawn - 8/09/2020 9:40 PM
Rating Added: 3
Great place in Iowa for all levels of divers to get wet. Perfect place for training. There are 3 training platforms, a couple of boats, a safe, a coffin, some cars, etc. There were plenty of fish to see including blue gill, muske and bass.
scubaboy - 6/06/2015 10:42 PM
Rating Added: 2
Not great, but not bad...and quite a bit better than some I’ve dived. I’ve used Big Blue for training, and OW Cert dives. It’s cold (isn’t all freshwater cold?), but not horribly so at the right time of the year (mid-late summer, early fall), but nice dive platform (love that!!) and some interesting stuff, and a few fish to make it a moderately interesting dive.