Well water — Sebastian, Florida

Private wells in Sebastian are overseen by the Florida Department of Health in Indian River County for wells under 6 inches and by the St. Johns River Water Management District for larger wells.

A Sebastian home on a private well is outside the reach of any utility's testing program, so the agencies involved are regulators rather than suppliers. The Florida Department of Health in Indian River County, known as DOH-Indian River, holds delegated jurisdiction from the St. Johns River Water Management District over every water well less than 6 inches in diameter in Indian River County. The district keeps responsibility for wells 6 inches in diameter or larger. For a Sebastian homeowner, the size of the well casing decides which agency issues the permit.

Indian River County is one of a minority of Florida counties where the health department, not the water district, issues household well permits. The state Florida Department of Health lists Indian River among the county health departments delegated to perform the well permitting program, alongside neighbors Brevard, St. Lucie and Okeechobee. The statewide construction rules sit in Chapter 62-532 of the Florida Administrative Code, and the St. Johns district adds its own Chapter 40C-3.

The county office is plain about who carries the burden. Its private well page states that the responsibility is upon the property owner to ensure that the water produced by their well is safe to consume. Last verified: October 10, 2026, on the Florida Department of Health in Indian River County website.

Sebastian well owners can have water tested at the Florida Department of Health in Indian River County laboratory, which charges $35 per sample as of October 10, 2026.

DOH-Indian River runs its own laboratory. According to the county testing page, the Florida Department of Health in Indian River County recommends testing private well water for bacteria at least once a year, and the office holds National Environmental Laboratory Accreditation Program certification for microbiological testing. Staff supply collection containers and instructions so the owner can draw the sample.

As of October 10, 2026, samples brought to the Indian River County office are tested onsite for a fee of $35 per sample, and department staff will come to a Sebastian home to collect samples for an additional fee. Lab staff explain the results and advise on next steps if a sample shows contamination. The statewide Department of Health guidance recommends testing for both bacteria and nitrate at least once per year and quotes a usual county charge of $20 to $30 per sample, so the Indian River County fee sits above that statewide range.

Other tests depend on location. The state guidance notes that additional water tests may be recommended depending on past and present land use activities nearby, and that private state-certified laboratories are also available. DOH-Indian River states that it will advise individuals on what contaminants they may encounter, how they can test for them and how they may be reduced or eliminated, so the county office in Indian River County is the starting point for a Sebastian owner deciding which extra tests apply to an address.

A Sebastian well under 6 inches in diameter needs a permit from the Florida Department of Health in Indian River County before it is built, repaired or abandoned.

Anyone who plans to construct, repair or abandon a well under 6 inches in Indian River County must first obtain a permit from DOH-Indian River, and the application can be filed by the owner or by a licensed water well contractor. The governing rules, the county page says, are Chapter 373 of the Florida Statutes and Chapters 62-532, 64E-8 and 40C-3 of the Florida Administrative Code, which cover contractor licensing, construction methods and minimum setback distances to sanitary hazards such as septic drainfields.

Old paperwork is often findable. DOH-Indian River notes that existing well construction documents for Indian River County can be found through the free online system called Septic Search, the same tool used for septic permits. For a buyer looking at a Sebastian house with a well, that record shows when and how the well was built before the sale closes.

Wells that serve more than one household fall under different rules. The state guidance says a well providing water to 2 or more rental residences, or to a business, day care or similar facility, counts as a public water system rather than a private well. The limited use public water system program, run locally by county health departments under Chapter 64E-8, includes setback standards for private water systems and construction standards for multi-family water systems. Under the state thresholds, a system serving fewer than 25 people and fewer than 15 connections is a limited use system regulated by DOH, while larger ones fall to DEP, so a small shared well on a Sebastian rental property moves from owner responsibility into routine required testing.

Wells in Sebastian and the rest of Indian River County tap either the shallow surficial aquifer system or the deeper Floridan aquifer system, according to the U.S. Geological Survey.

Two water bodies underlie Sebastian. The U.S. Geological Survey report Geohydrology of Indian River County, Florida (1988) names the surficial aquifer system and the Floridan aquifer system as the sources of groundwater used in Indian River County. Statewide, the Department of Health reports that about 88 percent of Florida residents are served by public water systems, and the other 12 percent rely on limited use systems and private wells, the group that includes Sebastian homes outside county water lines.

The two differ sharply. The USGS found that most wells tapping the Floridan aquifer system in the county flow on their own, at rates of 30 to 2,000 gallons per minute, and that about 65 percent of groundwater use was irrigation drawn from the Floridan. Chloride in the surficial aquifer generally ran below 100 mg/L, while Floridan water often exceeded 250 mg/L, and the report identified saline water beneath the fresh groundwater throughout the county as the chief water quality problem. Those figures are from 1983 and 1984 data, the most recent the report covers for Indian River County.

The shallow aquifer produces well too. The USGS reported transmissivities of 1,500 to 11,000 square feet per day in the surficial aquifer system in eastern Indian River County, the side of the county that includes Sebastian, with well yields as much as 1,200 gallons per minute. It also tracked the Vero Beach well field, where average chloride in six surficial wells rose about 36 mg/L between 1976 and 1983 as pumping grew from 5.44 to 8.00 million gallons per day, an early record of what heavy pumping does to the shallow aquifer along the Indian River Lagoon.

Public supply draws from the same ground. In February 2023 Sebastian Daily reported that Indian River County operates 7 wells at each of its two water treatment plants, 14 in all, and was approaching the maximum 12.8 million gallons per day permitted by the St. Johns River Water Management District and the Florida Department of Environmental Protection, during talks over a 2,000 acre Sebastian annexation.

Septic systems and water district irrigation limits both reach Sebastian wells, through the Indian River County sewer program and St. Johns River Water Management District rules.

Wells and septic tanks share the same sandy ground in Sebastian, and county programs treat them together. The Indian River County Septic-to-Sewer Program lists protecting drinking water sources by reducing groundwater contamination among the benefits of connecting homes to central sewer. The county has also linked the two utilities in policy: in October 2025, WQCS reported that county utility staff asked commissioners to suspend the county's 'no sewer without water' requirement as a cost saving step for septic conversions, a policy that directly touches Sebastian homes that pair a private well with a septic tank.

Irrigation from a backyard well is not exempt from water district limits. The St. Johns River Water Management District states that its landscape irrigation restrictions apply to private wells and pumps, ground or surface water and water from public and private utilities, so an irrigation well on a lot in the Sebastian Highlands follows the same schedule as a county water customer next door.

The state also watches wells near known pollution. The Well Surveillance Program, created in 1984 and shared by the Florida Department of Environmental Protection and the Department of Health, has surveyed over 19,000 sites and sampled over 54,500 wells since 2005, with field work done by county health staff such as those in Indian River County. Its well and facility tables were last updated on September 23, 2026. Separately, the Department of Health's Florida Water Management Inventory completed its parcel map of drinking water sources and wastewater methods for Indian River County in February 2023, the map that shows which Sebastian parcels use a private well.