How many wastewater permits expire in Illinois in 2028?

70 NPDES permits held by publicly owned wastewater treatment plants in Illinois expire in 2028, covering a combined average flow of 13 MGD. The busiest month is Mar 2028 with 20 expiries.

What happens when an NPDES permit expires?

The plant must have applied for renewal at least 180 days before the expiry date. If the agency has not reissued the permit by then, the old permit is administratively continued and stays enforceable. The reissued permit typically carries updated effluent limits based on the latest water-quality standards, which is what drives upgrade projects.

Which is the largest plant with a permit expiring in Illinois in 2028?

Cambridge Stp, Village Of in Cambridge, treating about 0.87 MGD under permit IL0061255, expiring Sep 2028.

How do I get contacts for the plants on this list?

Every plant links to its profile with flow, permit and compliance data. Treatment technology and verified decision-maker contacts for each plant, and the same list for every state and year, are available in Klarifi with a free account.

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Illinois wastewater permits expiring in 2028

Name: Illinois NPDES permits expiring in 2028
Creator: Klarifi
License: https://klarifi.io/terms-of-service

70 NPDES permits · 13 MGD combined average flow

70 publicly owned wastewater treatment plants in Illinois hold NPDES permits that expire during 2028, issued by Illinois Environmental Protection Agency. The table lists each plant with its permit number, expiry month, average flow, treatment technology and three-year violation count, in order of expiry.

An NPDES permit runs for five years. To keep discharging, a plant must apply for renewal at least 180 days before the expiry date, and the renewed permit usually arrives with tighter effluent limits, new monitoring requirements or a compliance schedule. That is why the year a permit expires is the year a plant starts budgeting for upgrades: nutrient removal, disinfection, capacity or controls.

Other years:

2026 (21)2027 (303)All Illinois NPDES permits →

Publicly owned wastewater treatment plants in Illinois with NPDES permits expiring in 2028, from EPA ICIS-NPDES records. Refreshed on every release.
Facility	City	Avg flow (MGD)	NPDES permit	Expires	Violations (3y)
Hinckley Stp, Village Of	Hinckley	0.32	IL0050628	Jan 2028	7
Alexis STP	Alexis	0.23	IL0021211	Jan 2028	175
Hurst Stp, City Of	Hurst	0.18	IL0029246	Jan 2028	65
Freeburg East Stp, Village Of	Freeburg	0.14	IL0020753	Jan 2028	1
Green Valley STP	Green Valley	0.02	IL0058998	Jan 2028	3
Golconda, City Of	Golconda	0.0064	IL0077496	Jan 2028	81
Arthur Stp, Village Of	Arthur	0.59	IL0021741	Mar 2028	18
Tuscola - Southside STP	Tuscola	0.4	IL0026107	Mar 2028	7
Mt Sterling - Stp, City Of	Mount Sterling	0.39	IL0022411	Mar 2028	55
Sesser Stp, City Of	Sesser	0.35	IL0031020	Mar 2028	3
Henry Stp, City Of	Henry	0.31	IL0070548	Mar 2028	10
Camp Point STP	Camp Point	0.25	IL0050458	Mar 2028	1
Thomson Stp, Village Of	Thomson	0.21	IL0073890	Mar 2028	18
Chrisman Stp, City Of	Chrisman	0.17	IL0028126	Mar 2028	185
Royalton Stp, Village Of	Royalton	0.17	IL0023337	Mar 2028	28
Mount Carroll Stp, City Of	Mt. Carroll	0.14	IL0020176	Mar 2028	0
Trenton STP	Trenton	0.11	IL0026701	Mar 2028	9
Cobden Stp, Village Of	Cobden	0.09	IL0028169	Mar 2028	12
Erie STP	Erie	0.06	IL0020303	Mar 2028	37
Neponset Stp, Village Of	Neponset	0.06	IL0076589	Mar 2028	20
Dallas City Stp, City Of	Dallas City	0.05	IL0028312	Mar 2028	32
Baldwin STP	Baldwin	0.05	IL0027219	Mar 2028	23
Hammond Stp, Village Of	Hammond	0.04	IL0027197	Mar 2028	12
Thompsonville STP	Thompsonville	0.04	IL0072478	Mar 2028	0
Ruma Wwtp, Village Of	Ruma	0.01	IL0063282	Mar 2028	28
Dubois Stp, Village Of	Du Bois	0.0044	IL0066249	Mar 2028	1
Petersburg Stp, City Of	Petersburg	0.31	IL0022233	Apr 2028	77
Kirkland Stp, Village Of	Kirkland	0.23	IL0064092	Apr 2028	5
Maroa Stp, City Of	Maroa	0.2	IL0025208	Apr 2028	95
East Cape Girardeau	East Cape Girardeau	0.008	IL0070319	Apr 2028	9
Hutsonville STP	Hutsonville	—	IL0029254	Apr 2028	10
Farmington Sanitary District STP	Farmington	0.52	IL0059790	May 2028	0
Mount Olive North STP	Mount Olive	0.48	IL0036528	May 2028	21
Hutsonville WWTP	Hutsonville	0.07	IL0080253	May 2028	4
Marseilles - South Stp, City Of	Marseilles	0.05	IL0071498	May 2028	0
Georgetown Stp, City Of	Georgetown	0.62	IL0022322	Jun 2028	0
Pinckneyville STP #1	Pinckneyville	0.52	IL0021997	Jun 2028	67
Aledo South Stp, City Of	Aledo	0.3	IL0027316	Jun 2028	0
Brookport STP	Brookport	0.05	IL0027782	Jun 2028	15
Kenney STP	Kenney	0.008	IL0024856	Jul 2028	51
East Alton Stp, Village Of	East Alton	0.59	IL0023094	Aug 2028	0
St Charles Main Stw East, Stw West	Saint Charles	0.45	IL0026808	Aug 2028	0
Lewistown WWTP	Lewistown	0.33	IL0020320	Aug 2028	6
Metamora South Stp, Village Of	Metamora	0.27	IL0021521	Aug 2028	6
Granville Stp, Village Of	Granville	0.24	IL0022331	Aug 2028	90
Cowden STP	Cowden	—	IL0028231	Aug 2028	67
Cambridge Stp, Village Of	Cambridge	0.87	IL0061255	Sep 2028	2
Arcola Stp, City Of	Arcola	0.59	IL0027499	Sep 2028	131
Cuba WWTF	Cuba	0.21	IL0020311	Sep 2028	54
West Liberty - Dundas STP	Dundas	0.15	IL0077879	Sep 2028	19
Zeigler Stp, City Of	Zeigler	0.14	IL0023299	Sep 2028	65
Hebron Wwtp, Village Of	Hebron	0.1	IL0026433	Sep 2028	4
Onarga Stp, Village Of	Onarga	0.05	IL0076813	Sep 2028	13
Damiansville Stp, Village Of	Albers	0.04	IL0063762	Sep 2028	29
Vermont Sd STP	Vermont	0.03	IL0049654	Sep 2028	29
New Boston Stp, City Of	New Boston	0.03	IL0074926	Sep 2028	15
Maeystown Stp, Village Of	Maeystown	0.0044	IL0071226	Sep 2028	306
Aviston Stp, Village Of	Aviston	0.09	IL0020001	Oct 2028	5
Lostant Wastewater Treatment Plant	Lostant	0.03	IL0075221	Oct 2028	175
Glasford Stp, Village Of	Glasford	0.36	IL0022527	Nov 2028	23
Tampico Stp, Village Of	Tampico	0.05	IL0022381	Nov 2028	8
Iola Stp, Village Of	Iola	0.04	IL0078379	Nov 2028	1
Anna Stw, City Of	Anna	0.38	IL0027481	Dec 2028	24
Winchester Stp, City Of	Winchester	0.15	IL0031801	Dec 2028	0
South Wilmington East Brooklyn STP	South Wilmington	0.14	IL0054321	Dec 2028	1
Coyne Center Sanitary District - STP	Milan	0.05	IL0065200	Dec 2028	12
Savanna Army Depot Activity	Savanna	0.02	IL0027049	Dec 2028	24
Huey Stp, Village Of	Huey	0.02	IL0075884	Dec 2028	0
Karnak Stp, Village Of	Karnak	0.0063	IL0062634	Dec 2028	28
Alto Pass Stp, Village Of	Alto Pass	0.0048	IL0080128	Dec 2028	63

Illinois permit renewals in 2028: questions

Sources and methodology

Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.

Data refreshed October 5, 2026.

Wastewater terms: NPDES permit · POTW · Biological nutrient removal · Tertiary treatment · Filter press · FOG · all terms

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