Buying Land in Indiana: What the State Controls Before a County Gets Involved

County zoning is optional in Indiana -- and a real number of counties have none

Indiana zoning and planning authority for counties, cities, and towns all comes from one statute, IC 36-7-4, often called Indiana's "advisory planning law." Unlike states where zoning is close to universal, Indiana law does not require any county to adopt zoning -- a county plan commission and zoning ordinance are things a county board chooses to establish, not a default. Reporting citing Indiana Farm Bureau's land-use materials puts the number at roughly 80 of Indiana's 92 counties having adopted county-wide zoning, meaning a real minority -- concentrated in more rural parts of the state -- have no comprehensive zoning ordinance in place at all.

This matters enormously for a buyer: in an unzoned Indiana county, there is no zoning department to call about your intended use, no use-district map, and no zoning variance process, because there's no zoning ordinance to vary from. That doesn't mean anything goes -- subdivision control ordinances, building codes, health department septic rules, and any applicable floodplain or drainage regulations still apply -- but the land-use restrictions that a zoning map would otherwise impose simply aren't there. The first call for any Indiana parcel should be to the county (or, in some places, an area or metropolitan) plan commission to find out whether zoning exists at all before you ask what it allows.

Where Indiana counties do zone, IC 36-7-4 also allows jurisdictions to combine: an "area plan commission" can be jointly established by a county together with one or more of its municipalities, giving the combined territory one plan commission and one zoning ordinance instead of separate city and county rules, and some Indiana plan commissions cover more than one county. Indiana townships are not a zoning authority under this statute at all -- zoning power in Indiana runs through counties, municipalities, and these area/metropolitan plan commissions; township government in Indiana instead handles functions like fire protection and township assistance (poor relief) in unincorporated areas, not land-use regulation. See our national guide to zoning for the general process once you've confirmed which body, if any, controls your parcel.

Septic: statewide ISDH rules, permitted through the local (county) health department

Indiana regulates septic systems -- "onsite sewage systems" in the state's terminology -- under 410 IAC 6-8.3, adopted by the Indiana State Department of Health (ISDH). This rule sets statewide design, siting, and construction standards, including soil and site evaluation requirements, for systems serving single- and two-family dwellings and similar small structures.

As in most states with this structure, the state agency sets the rulebook but doesn't issue the permit: day-to-day permitting, plan review, and inspection are delegated to local health departments -- in practice, the county health department covering the parcel. Anyone installing, repairing, or modifying a residential system must also hold a valid installer registration issued by ISDH, so confirming your installer's credential is part of the same process. Because the technical rule is uniform statewide but administered locally, expect the substance of what's required to be broadly consistent across Indiana counties, with specific fees, scheduling, and site-visit turnaround varying by health department. See our national guides to perc tests and septic systems for the general process.

Water rights: reasonable-use riparian doctrine, with a state registration threshold for large withdrawals

Indiana follows the common-law reasonable-use doctrine for water rather than a prior-appropriation permit system: a landowner may generally make reasonable use of surface water and groundwater on their property, so long as that use doesn't unreasonably interfere with other users' rights to the same water source. Indiana does not require a permit for an ordinary domestic well or typical small-scale agricultural use.

Layered on top of that common-law right is a registration and reporting requirement for large users under the Water Resource Management Act, IC 14-25-7. A "significant water withdrawal facility" -- defined by statute as any combination of a person's water withdrawal facilities capable of withdrawing more than 100,000 gallons of groundwater, surface water, or both combined in a single day -- must be registered with the Indiana Department of Natural Resources' Water Rights and Uses Section within three months of the facility being completed, and its owner must report annual water-use volume within three months after each calendar year ends. This is registration and reporting for inventory purposes, not a permit that can be denied; but a buyer planning a large irrigation system, a bottling or processing operation, or another water-intensive commercial use should check the projected withdrawal capacity against that 100,000-gallon threshold well before closing.

What this page does not tell you

Everything above is the state-level layer. Whether your target county has adopted zoning at all -- and if not, what other local ordinances (subdivision control, drainage, floodplain) still apply -- what a specific zoning district and its setbacks allow where zoning does exist, and your county health department's specific septic fees and site-evaluation scheduling are all determined locally and are not standardized across Indiana. See our national guides to zoning, perc tests, and septic systems for how those local conversations typically go.