Mercer County, Illinois
Keithsburg is a city in Mercer County, Illinois. Keithsburg adopts its own zoning, so inside its limits Keithsburg’s rules apply, not the county’s. 9 rules below are quoted from official sources and independently re-checked, most recently on November 2, 2026. Rules for unincorporated land are on the Mercer County page.
New dwellings and buildings inside Keithsburg city; placement of preconstructed buildings and advertising signs also requires permits.
“the zoning enforcer shall deny a permit for any new dwelling or building, unless the application makes provision for connection to sewage handling facilities”
All land inside Keithsburg city limits (Keithsburg, Mercer County, Illinois). The city's own official site links its zoning regulations and zoning application, and names its zoning enforcer.
“zoning regulations can be read by clicking the link above.”
All land inside Keithsburg city limits
“for purposes of this title, the city is hereby divided into districts designated as follows: • a residential district e recreational district b business district cd industrial district”
New dwellings in the a residential district (Chapter 5, Section 10-5-3) inside Keithsburg city
minimum floor area, one-story dwelling: >= 500 square feet · minimum floor area, dwelling with two or more stories: >= 750 square feet
“one story dwellings shall be constructed with not less than five hundred (500) square feet of floor area.”
Lots in the a residential district (Chapter 5, Section 10-5-2) inside Keithsburg city, for a single-family dwelling; the two-family lot rule is in the same section.
minimum lot area, single-family dwelling: >= 3000 square feet · minimum lot width, single-family dwelling: >= 30 feet · minimum lot area, two-family dwelling: >= 5000 square feet (applies to two-family dwelling lots only; minimum width 50 feet)
“every lot or tract of land upon which a single-family dwelling is to be constructed shall have an area of not less than three thousand (3,000) square feet and a minimum width of thirty feet (30').”
Lots in the a residential district inside Keithsburg city (front from road right-of-way; side and rear from adjoining lines)
front setback from road right-of-way: >= 25 feet (a block-average exception applies where 75 percent or more of frontage is nonconforming) · side setback from adjoining private property: >= 5 feet · rear setback, lot not adjacent to alley: >= 30 percent of lot depth (rear setback of 5 feet where rear lot line is adjacent to an alley)
“rear yard depth shall be a minimum of five feet (5') for lots whose rear property line is adjacent to an alley and a minimum of thirty percent (30%) of the lot depth for lots whose rear property line is not adjacent to an alley.”
Campgrounds for recreational vehicles in the e recreational district of Keithsburg city only; not a rule for the residential district
RV parking site area: >= 750 square feet (per recreational vehicle site in an e recreational district campground)
“campground for recreational vehicles; provided, that a graveled or otherwise improved parking site of at least seven hundred fifty (750) square feet shall be provided for each recreational vehicle and that each such parking site shall have access from a graveled or otherwise improved roadway, and in the case of nonmotorized vehicles, a parking area off the public right-of-way shall be provided for one motor vehicle per nonmotorized recreational vehicle.”
A new dwelling or building inside Keithsburg city that can connect to the public sanitary sewer
public sewer lateral distance threshold: <= 200 feet (Connection not required where the lateral is longer than 200 feet)
“and if said dwelling or building can be connected to the public sanitary sewer and if such connection can be done with two hundred feet (200') or less of the lateral sewer line, then the zoning enforcer shall deny a permit unless such connection is provided.”
Zoning permits for construction inside Keithsburg city
“zoning regulations can be read by clicking the link above. to learn more about mobile homes and mobile home parks, click here. click here for a zoning application.”
We looked and could not find an official answer yet. Silence is not permission; ask Keithsburg or Mercer County directly.
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.
Unanswered questions are usually a sign that Keithsburg publishes no rule on the point, not that none exists. Mercer County’s page lists the county offices to call.
Off-grid gear
Going off-grid in Keithsburg means bringing your own water and power. The kit we’d start with:
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