Off-Grid Living in Harrison County, Mississippi

If you're eyeing off-grid land in Harrison County, Mississippi, the first thing to know is that this county is a bit of an exception in the state: it actually has countywide zoning, administered through a Unified Development Code by the Harrison County Office of Zoning. Most rural Mississippi counties skip zoning entirely, but Harrison doesn't, so you can't assume "county land = no rules." That said, if your goal is off-grid homesteading, the county's A-1 General Agriculture District is your friend. It's meant for farming, silviculture, dairying, and livestock, though it's aimed at larger parcels (15+ acres). Smaller lots fall into other districts where uses are more restricted, so I'd confirm your parcel's zoning with the county before buying.

One important wrinkle: the incorporated cities inside the county, Gulfport, Biloxi, D'Iberville, Long Beach, and Pass Christian, run their own separate zoning and building departments. Everything in this guide is about unincorporated county land. If you're inside city limits, the rules are different and you'll need to talk to that city's planning office directly.

On dwellings: I couldn't find a specific county ordinance addressing tiny homes on wheels for full-time living outside an RV park. Mobile and manufactured homes go through Code Administration's permit process, which requires septic sign-off from the health department before the power company will connect service. Some commercial sources suggest THOWs get treated like RVs here, but that's not confirmed through an official county document, so ask Code Administration directly if this is your plan.

Septic is handled through a layered system: state baseline rules come from the Mississippi State Department of Health's On-Site Wastewater program, but the Harrison County Health Department actually issues the permits, especially for residential lots under three acres. You'll need a soil evaluation and, once installed, a final certificate of acceptance before Code Administration will let the power company hook up your electric. That utility-hookup-tied-to-septic-approval structure is worth flagging if you're planning to go off-grid on power: the permitting process is built assuming eventual grid connection, even though nothing I found explicitly bans solar-only setups.

Greywater doesn't have its own county ordinance that I could locate, so it falls under the same wastewater disposal rules as septic, per MSDH and the county health department. Rainwater harvesting looks fine, no county restriction turned up in this research. Private wells are permitted, with the health department handling water sampling and any state licensing requirements for well drillers, but I didn't find a Harrison County-specific well ordinance beyond that.

Bottom line: unincorporated Harrison County can work for off-grid living, especially on larger agricultural-zoned parcels, but septic and building permits are tightly linked to the utility company confirming a hookup, and several off-grid specifics (THOWs, composting toilets, greywater exemptions) just aren't spelled out clearly in what I found. Call the county offices below before you commit to a plan.