Baker Creek feeds the lake from the south — the sole inlet stream, and the reason you launch on a creek rather than the lakeshore. Flint Creek leaves the northeastern corner for the Hillsborough River, Tampa's water supply, through an adjustable SWFWMD weir that manages the lake's stage. There is no lock and no boat passage at the structure — the lake is where your trip ends.
The lake's stage is managed: SWFWMD's adjustable weir at the Flint Creek outlet holds a relatively constant, somewhat elevated level through dry spells, so it does not free-fall in a dry spring the way an unregulated Florida lake does. No current stage reading or adopted minimum level is published. Depth runs about 13 feet at the very most with a mean under seven (USF's 2013 survey), which is why the wind stirs it and the algae runs it. Algae has no off-season here — DOH-Hillsborough posted eight blue-green algae alerts for this lake between August 2025 and July 2026, the latest issued July 15, 2026 and still standing at the end of the month. Native eelgrass collapsed decades ago; hydrilla, water hyacinth and cattails dominate, with county treatment ongoing.
Plain English Summary
| Trotlines, lake-specific | FWC's Southwest Region freshwater special regulations state, verbatim, that on Lake Thonotosassa "Trotlines may be used from sunset until 9 a.m. Sunday through Thursday." This is a lake-specific rule that does not apply on most nearby water. |
| Channel catfish, lake-specific | "No bag limit for channel catfish" on Lake Thonotosassa, per FWC's Southwest Region freshwater special regulations. Statewide size and gear rules still apply. |
| Fish Management Area status — unresolved | FWC's black bass and catfish forecast pages both label this water "Lake Thonotosassa FMA." We could not reach an FWC Fish Management Area roster to confirm or refute the designation, and we could not reproduce a Hillsborough FMA list on the eRegulations Southwest Region page across repeated reads. UNRESOLVED — we are not telling you that FMA rules do or do not apply here. The two lake-specific rules above stand on their own regardless. If you plan to fish gear or limits that would turn on FMA status, call FWC's Southwest Regional Office before you go. |
| Fishing licence and general rules | Standard Florida freshwater fishing rules apply — a freshwater fishing licence may be required, and statewide size, bag and gear regulations govern anything the two lake-specific rules above do not. |
| Motor and horsepower restrictions | We found no horsepower cap, gas-motor ban, electric-only rule or lake-wide idle/no-wake zone for Lake Thonotosassa in FWC's boating regulations pages, Florida Administrative Code Ch. 68D-24 (the boating-restricted-area section we could reach, 68D-24.008, covers Broward County only), the FWC/eRegulations Southwest Region special regulations, or Hillsborough County's ramp and location pages. The gas-motor bans on that eRegulations page attach to Bobby Hicks Park Pond and Gadsden Park Pond, not to this lake. We did not read the Hillsborough County code of ordinances directly, so read this as "none published in the sources named," not as a guarantee. The practical ceiling here is hull length, not horsepower — see the boat-size note below. |
| Boat size | Not a written rule, but a hard practical limit. FWC's crappie and catfish forecasts describe a public boat ramp at the southern end that accommodates fishing boats under 20 feet plus kayaks and canoes, and the USF/FCCDR ramp survey sheet says the ramp handles small to mid-sized boats "approximately twenty (20) feet long" and is "most commonly utilized by airboats, small fishing boats, and personal watercraft." |
| Launch fee and hours | Hillsborough County's boat ramps page states a "$5 for launching boats" fee, and "$2 additional entry applies when launching boats at Conservation Parks." Baker Creek is a stand-alone ramp, not a Conservation Park, so the $2 entry does not attach. The county also sells an annual boat ramp pass hang tag for $100 (Conservation Parks & Boat Launch Passes page, "Last Modified: 7/7/2026, 4:25:21 PM"), good for county boat ramps only — it does not include park entry. The ramp is open sunrise to sunset. |
| Swimming and contact | Under the July 15, 2026 DOH-Hillsborough blue-green algae health alert, do not swim, wade or use personal watercraft where there is a visible bloom, keep pets and livestock out, and wash skin and clothing after any contact. There is no public swimming beach on this lake in the county, SWFWMD or USF Water Atlas sources we read. |
| Full legal text | Official boating regulations → |
Can you swim in Lake Thonotosassa?
Is it safe to eat fish from Lake Thonotosassa?
Where do you launch on Lake Thonotosassa?
How long is the run from the Baker Creek ramp to open water?
What is the fishing like on Lake Thonotosassa?
How big and how deep is Lake Thonotosassa?
Lake Thonotosassa is the largest natural lake in Hillsborough County — about 946 acres by USF's 2013 survey, though FWC's pages say 820 — and it is shallow, wind-mixed and algae-dominated: roughly 13 feet at most, mean under seven, hypereutrophic and listed impaired, with blue-green algae alerts arriving almost monthly. Fish it, don't swim in it. Anglers come for trophy black crappie in unusual numbers, bluegill and redear that run large, bass in the 5–9 pound class, and channel catfish with no bag limit at all.
The only public launch is the Baker Creek ramp at 12095 Thonotosassa Rd — on a canal, not the lakeshore, so you back into the creek and run out to open water. Hours are sunrise to sunset, the launch fee is $5, and the practical boat ceiling is about twenty feet; airboats are routine traffic. Nobody publishes the creek run's length or depth, so idle out and read the water in a dry spring. Trotlines are legal from sunset until 9 a.m. Sunday through Thursday. Hurricane Milton put the lake's outlet structure completely under water in October 2024; the county's ramp index, updated well after the storm, still carries Baker Creek as active.