Mosquito Control District — Indian River County, Florida

The Indian River Mosquito Control District is a special taxing district with its own elected board, separate from the Board of County Commissioners, run from a 10-acre campus at 5655 41st Street in Vero Beach.

Asked whether it belongs to county government, the district answers no: it is a special taxing district governed by a separate Board of Commissioners and Director, and the Legislature created it in 1925 (IRMCD Mosquito FAQ). The Florida Department of Agriculture and Consumer Services certifies it as a state mosquito control program (IRMCD About Us).

Its current charter is Chapter 2006-344, Laws of Florida. That act folded the 1925 creating act, chapter 11128, and eleven later special acts into one text, abolished the old district and re-created it as a new special taxing district in Indian River County (Chapter 2006-344). Chapter 2011-243 later rewrote parts of it, among other things deleting the board's power to eliminate all species of mosquitoes and sandflies in the district (Chapter 2011-243).

The 41st Street buildings went up in 1967, with additions and renovations in 2000 and 2006, and hold the main office with laboratories, a shop, vehicle bays, chemical storage and a poultry-raising building (IRMCD About Us). The district runs more than 30 vehicles, typically about 10 all-terrain vehicles for its Inspector/Sprayers, heavy-duty impoundment pumps along the Indian River Lagoon and several boats used mainly for larval inspections.

The district covers the eastern two-thirds of Indian River County, the part lying east of a surveyed line that follows the Range 36 and 37 line up to State Road 60 and then the Lateral S Canal north.

The legal boundary is written out in the charter. Starting at the south county line, it runs north along quarter-section lines, then north on the Range 36 and 37 line to the north right-of-way of State Road 60, east 732.15 feet to the east right-of-way of Lateral S Canal of the Fellsmere Farms Company subdivision, and north along that canal to the county's north line; everything east of it is in the district (Chapter 2006-344, section 1).

The district also publishes a map, but only as an image: it shows the county boundary in white, the district boundary in red and the truck spray zones in black (IRMCD District Map). The text of that page names no towns, so whether a given address in the western county falls inside has to be read off the map or asked of the office.

Inside the district, effort is not spread evenly. The district limits its larval control to the two salt marsh species produced primarily east of US 1, and its crop duster treats the marshes along the river and the barrier island rather than the western part of the district (IRMCD Mosquito FAQ). The reason it gives is range: salt marsh mosquitoes can fly up to 25 miles once they become adults.

Three commissioners elected by voters inside the district set policy and the budget, and the money comes mainly from a property tax that the Indian River County tax collector adds to the yearly bill.

Commissioners run in nonpartisan elections for four-year terms, staggered so that one seat is filled at one general election and two seats at the next (Chapter 2011-243). Two members make a quorum, two votes are needed to act, and the charter sets commissioner pay at $400 per month or a greater amount allowed by general law or special act (Chapter 2006-344). The district describes its structure as a Council and Administrator form: the board sets policy and approves the budget, and it appoints an administrator who runs day-to-day business and prepares the budget (IRMCD About Us). The commissioners listed on October 12, 2026 were Thomas Lowther, Janice Broda and Anna Kirkland, all reached by mail at 5655 41st Street, Vero Beach (IRMCD commissioners page).

Board meetings are public, and the district's home page lists the next three for October 13, November 17 and December 8, 2026 (IRMCD). A five-year strategic plan, which the district says is reviewed annually, won board approval at the regular February meeting on February 14, 2023 (IRMCD About Us).

The tax works through county offices. The charter lets the board levy up to 10 mills on taxable property in the district, by resolution adopted no later than July 15; the Board of County Commissioners then orders the county property appraiser to assess it and the tax collector to collect it with other taxes (Chapter 2011-243, section 10). The district's fiscal year runs October 1 to September 30, and the fiscal 2026-2027 certified budget is posted on its budget page.

The most recent budget summary read for this page is from fiscal 2022-23. It listed a millage of 0.2500 (labelled proposed millage in the final budget) on a gross taxable value of $23,341,464,151, for a local tax request of $5,835,366 (IRMCD FY 22-23 final budget). As arithmetic, 0.25 mills is 25 cents per $1,000 of taxable value, so $25 on a home taxed at $100,000. Later rates were not verified for this page.

The district's crews work the Indian River Lagoon marshes with impoundments and larvicides, spray adults from trucks at night, and remove mosquito sources such as waste tires and neglected pools.

Along the Indian River Lagoon shoreline, the district manages 4,500 acres of coastal mangrove swamp and salt marsh and works the impoundments with the U.S. Fish and Wildlife Service, the St. Johns River Water Management District and the Florida Department of Environmental Protection; district staff maintain most of the dikes and water control structures themselves (IRMCD Impoundment Management). That page says the district diked about 2,600 of the county's nearly 4,500 acres of coastal marsh in the 1950s and early 1960s, while the larviciding page puts the impounded share at about 2,000 acres. Two land records show the reach of that work: Hole-in-the-Wall Island, where 69th Street ends at the lagoon, passed to the district in 2009 and is a 130-acre mosquito control impoundment under a conservation easement, and in June 2015 it bought a half interest in a lot at 609 19th Street SE, shared with the Indian River Land Trust, as access to the South Bills Impoundment (IRMCD About Us).

Field inspectors check hundreds of known breeding sites for larvae and log each visit in a database, because regulations require proof that mosquitoes are present in a marsh before it is treated (IRMCD Larviciding). Small sites are treated on the spot; large areas go to a contracted flying service using fixed-wing aircraft.

Truck spraying is the main adult control method in the district. The spray is an ultra-low-volume mist metered by computer to the same amount per mile at any speed, logged by GPS and applied after sunset, when most mosquitoes are active; the district adds that night work lowers the risk to beneficial insects that fly by day (IRMCD Adulticiding). During widespread outbreaks or a threat of St. Louis encephalitis, West Nile or Zika, the district contracts aerial spraying of naled.

Source reduction covers backyards too. The district has collected tires since 1992, when state waste tire money first reached mosquito programs, and has kept going since that funding ended, removing over 1127 tons in 30 years (IRMCD Waste Tire Program). For an abandoned swimming pool, an inspector visits the reported address and usually stocks it with native mosquito fish (IRMCD Mosquito FAQ).

Residents from Sebastian to Vero Beach file a service request on the district's online treatment map or call 772-562-2393, and the same map shows where trucks or aircraft are scheduled.

The contact page sends anyone with high mosquito numbers, or who wants an inspector to look at a property, to the Service Request form, and lists the administrative office at 772-562-2393, fax 772-562-9619 and irmcd@irmcd.org (IRMCD Contact Us).

The map's colours tell residents what is coming. Yellow marks areas scheduled for aerial treatment in the next 48 hours, purple marks ground spraying planned in the next 24 hours, orange marks ground spraying in the last 7 days and red marks aerial treatment in the last 7 days; no colour means no ground or aerial treatment in the past week (IRMCD Treatment Map and Information).

Some complaints belong elsewhere. Ditch, swale and canal upkeep is outside the district's job, and its FAQ refers that work to the owner's homeowner's association, the local city or county Public Works office or the local water management district, depending on location (IRMCD Mosquito FAQ). Ditch larvae are also mostly outside its larval program, which the same FAQ limits to the two salt marsh species.

Last verified: October 12, 2026, on the Indian River Mosquito Control District's home, About Us, Commissioners, Budget, Contact Us, Treatment Map, Mosquito FAQ, Impoundment Management, Larviciding, Adulticiding and Waste Tire Program pages, and in Chapters 2006-344 and 2011-243, Laws of Florida.