Zoning, building permits and septic rules in Village of South Wilmington, Illinois

Village of South Wilmington’s own rules

• Building permitRequired

  Small-scale solar energy conversion systems (SSEC) inside South Wilmington village only. General building permits for other construction were not established.

  • Applies only to small-scale solar arrays under Ordinance No. 2025-04.
  • Plans must be stamped by a licensed structural engineer and by a qualified inspector for the installation.
  • Roof-mounted systems require a structural engineer's report on roof load.

  “a building permit shall be required prior to erecting any ssec.”

• Local zoningPresent (with conditions)

  Land inside South Wilmington village limits. The village's own ordinance refers to zoning districts and residentially zoned districts.

  • The village zoning ordinance title and district map were not located; this claim rests on the village's own references to zoning districts in Ordinance No. 2025-04.
  • Zoning is administered by the village; the separate Grundy County unified development ordinance applies only to unincorporated land.

  “small-scale solar energy conversion (ssec) systems shall be allowed as an accessory use in all zoning districts subject to the requirements listed below.”

Rules another office applies inside Village of South Wilmington

Village of South Wilmington does not set these itself; the county, a health district or the state does, and they apply to every address inside its limits.

• Who permits septicCounty (with conditions)

  Private sewage (septic) systems in Grundy County. Applies inside South Wilmington village only if the county program covers incorporated parcels, which the county page does not state.

  • The county page does not name its service area and does not address municipal sewer systems.
  • Confirm with Grundy County Environmental Health (815-941-3115) whether the village has public sewer, which would displace septic permits.

  “the environmental health division performs the following functions within the private disposal system program (aka septic systems): reviews proposed private sewage disposal system plans and applications.”

• Septic permitRequired

  Building permits for homes served by private septic systems in Grundy County, including land inside South Wilmington village if the county program applies there (not confirmed).

  • Requires an approved water and sewage system permit before a building permit is issued.
  • Village public sewer availability was not established; if public sewer serves the parcel, the county septic permit may not apply.

  “in order to obtain a building permit, you must have an approved water & sewage system permit.”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission; ask Village of South Wilmington or Grundy County directly.

• Owner-builder exemption — Owner-builder permit exemption inside South Wilmington village
• Building code adopted — Building code adopted by South Wilmington village
• Inspections — Building inspections for new homes inside South Wilmington village
• Certificate of occupancy — Certificate of occupancy for new homes inside South Wilmington village
• Zoning districts — Published zoning district map and schedule for South Wilmington village

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.