The state of Illinois keeps a log of every well ever drilled. We read all 305,166 of them.
Illinois well logs, made useful.
Every water well log the Illinois State Geological Survey holds — depth, the driller who filed it, and the original record — brought together around one address, instead of one record at a time.
✓ Verified against ISGS · 2026-08-20
140 ftmedian well depth statewide
15 gpmmedian well yield
12,527wells drilled since 2016
305,151wells you can look up by location
What you can answer here
- How deep will my well need to be? Median and range of actual drilled depths near you — not national averages.
- What will it cost? Local median depth × published per-foot rates, with the math shown.
- Will it produce enough water? Yields from pump tests on nearby wells.
- Who drills around here? The drillers who actually filed recent well logs in your county.
These are ISGS records
Every figure here comes from the Illinois State Geological Survey water well records — the state's official well-log repository. We index those same records by location so you can start from an address, and every well links back to its original filed log.
Buying property with a well — or land you'd need to drill?
See every recorded well near any Illinois address: depths, water levels, yields, and links to the original driller's logs — all in one report.
Get the property report — $29Driller, agent, or inspector? Unlimited & white-label plans →
Well data by county
Adams County
1,529 wells · median 180 ft Alexander County
425 wells · median 115 ft Bond County
1,641 wells · median 38 ft Boone County
4,750 wells · median 165 ft Brown County
152 wells · median 195 ft Bureau County
3,153 wells · median 200 ft Calhoun County
336 wells · median 107 ft Carroll County
1,902 wells · median 240 ft Cass County
930 wells · median 67 ft Champaign County
5,388 wells · median 135 ft Christian County
2,038 wells · median 41 ft Clark County
1,151 wells · median 65 ft Clay County
1,260 wells · median 91 ft Clinton County
2,412 wells · median 38 ft Coles County
1,540 wells · median 65 ft Cook County
11,688 wells · median 200 ft Crawford County
1,190 wells · median 63 ft Cumberland County
1,086 wells · median 40 ft Dekalb County
3,554 wells · median 202 ft Dewitt County
1,368 wells · median 151 ft Douglas County
1,268 wells · median 81 ft Dupage County
10,728 wells · median 161 ft Edgar County
1,162 wells · median 66 ft Edwards County
221 wells · median 80 ft Effingham County
2,812 wells · median 46 ft Fayette County
2,761 wells · median 41 ft Ford County
1,202 wells · median 130 ft Franklin County
282 wells · median 120 ft Fulton County
1,356 wells · median 76 ft Gallatin County
601 wells · median 90 ft Greene County
685 wells · median 64 ft Grundy County
3,475 wells · median 168 ft Hamilton County
166 wells · median 298 ft Hancock County
940 wells · median 225 ft Hardin County
444 wells · median 202 ft Henderson County
921 wells · median 117 ft Henry County
2,794 wells · median 275 ft Iroquois County
2,416 wells · median 140 ft Jackson County
1,413 wells · median 180 ft Jasper County
1,112 wells · median 40 ft Jefferson County
632 wells · median 70 ft Jersey County
1,079 wells · median 85 ft Jo Daviess County
2,914 wells · median 220 ft Johnson County
465 wells · median 199 ft Kane County
12,422 wells · median 230 ft Kankakee County
7,079 wells · median 120 ft Kendall County
4,977 wells · median 235 ft Knox County
1,827 wells · median 180 ft Lake County
25,854 wells · median 154 ft Lasalle County
7,212 wells · median 165 ft Lawrence County
1,267 wells · median 98 ft Lee County
3,826 wells · median 192 ft Livingston County
2,378 wells · median 100 ft Logan County
1,785 wells · median 64 ft Macon County
2,287 wells · median 90 ft Macoupin County
1,480 wells · median 41 ft Madison County
4,601 wells · median 45 ft Marion County
1,255 wells · median 50 ft Marshall County
773 wells · median 105 ft Mason County
3,074 wells · median 98 ft Massac County
888 wells · median 111 ft Mcdonough County
1,263 wells · median 220 ft Mchenry County
22,936 wells · median 125 ft Mclean County
3,456 wells · median 146 ft Menard County
1,011 wells · median 48 ft Mercer County
1,579 wells · median 395 ft Monroe County
2,584 wells · median 210 ft Montgomery County
1,779 wells · median 40 ft Morgan County
1,180 wells · median 42 ft Moultrie County
851 wells · median 87 ft Ogle County
6,084 wells · median 200 ft Peoria County
4,865 wells · median 70 ft Perry County
550 wells · median 45 ft Piatt County
1,417 wells · median 141 ft Pike County
782 wells · median 115 ft Pope County
328 wells · median 185 ft Pulaski County
573 wells · median 80 ft Putnam County
773 wells · median 162 ft Randolph County
2,199 wells · median 72 ft Richland County
1,682 wells · median 180 ft Rock Island County
3,922 wells · median 220 ft Saline County
329 wells · median 140 ft Sangamon County
3,840 wells · median 40 ft Schuyler County
335 wells · median 73 ft Scott County
288 wells · median 68 ft Shelby County
2,517 wells · median 43 ft St. Clair County
4,597 wells · median 79 ft Stark County
492 wells · median 119 ft Stephenson County
3,208 wells · median 184 ft Tazewell County
4,738 wells · median 118 ft Union County
1,592 wells · median 250 ft Vermilion County
4,286 wells · median 95 ft Wabash County
727 wells · median 215 ft Warren County
1,602 wells · median 185 ft Washington County
857 wells · median 70 ft Wayne County
1,289 wells · median 120 ft White County
1,029 wells · median 100 ft Whiteside County
4,462 wells · median 120 ft Will County
21,549 wells · median 161 ft Williamson County
372 wells · median 154 ft Winnebago County
11,760 wells · median 135 ft Woodford County
3,156 wells · median 143 ft