The city's borders, which used to end at the county landfill, now stretch to the Howard Frankland Bridge and include the 2,600-acre Gateway Preserve.
The City Council voted unanimously Thursday to annex the property, despite the objections of county officials.
Gateway Preserve lies along the shore of Tampa Bay just north of Weedon Island. Most of the annexed property is a wildlife preserve owned by the state.
However, the deal also includes 149 acres of privately owned land, including a parcel on Gandy Boulevard scheduled for an 84 unit condominium tower called Grande Verandah. Two other parcels also are slated for development.
James M. Chadwick, one of four partners in the condominium project, said he enthusiastically supported annexation, especially after receiving help connecting his buildings to the city's water supply.
"We are excited to be a part of the city," he told council members.
Once completed, the developments are expected to add nearly $500,000 a year to the city's tax rolls, said Kevin Dunn, the city's managing director of development coordination.
City officials began exploring annexation of the Gateway Preserve last fall, saying it made sense from a planning perspective. County commissioners objected strongly and suggested it was a ploy by Mayor Rick Baker to move the city boundary closer to Feather Sound, which also is being considered for annexation.
County Administrator Steve Spratt was at the meeting to express concerns from the commissioners. Top among them was who would manage the environmentally sensitive preserve.
The state bought the land in the mid 1980s at the request of the county, which wanted to see it preserved from development. County money helped pay for the state's purchase and the county has managed the property since.
Baker said it was his intention to allow the county to continue managing the property. However, there was disagreement as to who should pay for the upkeep, which involves mosquito control and keeping exotic plants and animals from establishing themselves.
Because it will now be in the city's borders, Spratt said the city should pay for the maintenance. That prompted a few grumbles among some council members.
The county already maintains preserve areas throughout Pinellas, including parcels located in municipalities, at no additional cost, Baker said.
"Nothing has really changed here except the preserve is in the city instead of the unincorporated area," said council member Richard Kriseman.
But Baker proposed a compromise: The city and county will examine each maintenance project on a case-by-case basis and can search for grant money to cover them.
A handful of environmentalists were at the meeting to urge the council to continue protecting the preserve from development.
"This is the animals' land, the birds' land, the fishes' land," said local activist Bill Reed. "This is not land to be walked on."
Council members expressed their commitment to leaving the preserve unchanged. "Every morning when I drink my morning coffee, I look out over this beautiful preserve," said John Bryan, who lives next door. "I hope to keep it that way forever."