How Davis Islands was built from bay mud in the 1920s

Who built Davis Islands, and when?

Developer D.P. Davis built them in the 1920s. The City of Tampa says Davis was a Tampa native. He created the neighborhood from two small natural islands that sat at the mouth of the Hillsborough River. They were known as Little Grassy Key and Big Grassy Key.

Tampa Magazines adds dates. It says Davis moved back to Tampa in 1924 and opened the first land sales in early October 1924. The 1920s were the years of the Florida land boom. Developers across the state were making new land from shallow water.

You can read the City’s own summary on our Davis Islands neighborhood page.

How do you build an island out of bay mud?

You dredge it. The City says the land was built up from mud dredged from the bottom of Tampa Bay and expanded. Tampa Magazines describes the same method and says the dredged material was sand. The two sources use different words for the fill. This post uses the City’s wording.

The result was new ground that sits low. The City’s June 2020 sea level rise report says ground elevations in the Davis Islands basin range from sea level to 10 feet NAVD88. The whole basin is in the preliminary special flood hazard area in that report. Our companion post covers those numbers in detail: Davis Islands flood zones and seawalls.

Why is it called Davis Islands, plural?

Because it is more than one island. The City explains that a canal fully separates a portion of the island from the rest. That makes Davis Islands technically an archipelago.

It once had three islands. Airport construction changed that. The City says the end of one canal was filled in to make enough land for a runway. That connected the two largest islands at their southern ends. The count dropped to two.

How fast did the lots sell?

Very fast. Tampa Magazines says that on the first day, October 4, 1924, Davis sold all 300 available lots within three hours, for a total of $1,683,000. The article adds that more people wanted lots than there were lots to sell.

Davis died on October 13, 1926. By then, the article says, he had sold the Davis Islands development. Most of the buildings his company put up are still standing. The land boom itself ended soon after.

What else did Davis plan?

He planned a whole community with rules. Tampa Magazines says the single-family houses followed design guidelines set by D. P. Davis Properties. The same article describes Mediterranean revival, Italianate and Spanish styles.

The Tampa Magazines article says the Bay Isle Building, completed in 1925, is still the anchor of the island business district. Today the City describes the neighborhood as a mix of residential and retail areas surrounded by parks, green space and water views. It names Peter O. Knight Airport, the Davis Islands Yacht Club, Tampa General Hospital, the Sandra Freedman Tennis Complex and the Roy Jenkins aquatic center. Marjorie Park and the Marjorie Park Municipal Yacht Basin are also on the islands.

The City says Davis named Marjorie Park for his wife, Marjorie Merritt Davis, and donated it to the City.

What did the land boom leave behind?

It left a plan, a set of rules and a low island. The 1920s boom drew buyers fast, and developers shaped whole districts at once. On Davis Islands that meant canals, parks, a business district and house styles chosen by the developer.

Some of that is still visible. The City names parks, a yacht basin and a tennis complex. Tampa Magazines says the vast majority of the buildings and amenities the Davis company built are still standing. It also lists notable losses, including the golf course and the Coliseum.

The same article warns that demolition still threatens many original buildings. If you own an older house on the island, learn what is original before you plan changes.

What does this history mean for a new home today?

It means the land came first from the water, and the water still matters. Four points follow from the records.

• Ground is low. Check the flood zone for the exact address.
• Seawalls ring the island. Ask who owns the one at your lot.
• Canals and the bay shape the lot lines and the views.
• Fill and old plats affect what a surveyor finds. Order a survey early.

A new home on filled land still follows the same rules as any home in a flood area. An elevation certificate is part of the permit file in a mapped flood zone. Read our guide to elevation certificates for new construction for the steps.

You can see the kind of work Halo Homes publishes in Halo’s portfolio. Those pages show finished homes and do not describe a location.

What is the next step?

If you own or are studying a lot near the water, start with its flood zone and survey. Then talk about design, elevation and access. Halo Homes offers custom home construction in Tampa Bay and the surrounding regions. Call (813) 956-1972 or write through the contact page.