In Illinois: 14 plants hold a permit with a new or tighter discharge limit already written into it, taking effect between Jan 1, 2027 and Jan 1, 2031 (41 limits); 5 of them reported a median above that limit between Oct 1, 2025 and Sep 30, 2026. EPA's file of Oct 16, 2026.

By state: all · IA 204 · PA 172 · LA 165 · OH 134 · MS 68 · AR 58 · TX 57 · MI 53 · GA 52 · VA 52 · MD 48 · NJ 35 · IN 31 · SC 23 · KS 21 · MN 21 · NY 21 · MO 20 · WV 17 · OR 16 · IL 14 · FL 10 · NE 9 · OK 8 · TN 8 · CO 7 · UT 7 · NM 6 · CA 5 · SD 5 · CT 3 · ID 3 · ME 2 · WI 2 · AL 1 · DC 1 · KY 1 · MT 1 · NH 1 · PR 1 · VT 1 · WA 1

Plant	Permit	State	Type	Design flow	Parameter	New limit	Effective	Today's median	× limit
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	daily maximum 5.6 mg/L (Jan, Feb, Nov, Dec), new	Jan 1, 2027	11.9 mg/L (4 values)	2.12×
LINCOLN, CITY OF	IL0029564	IL	Sewage plant, major	10.27 MGD	Chlorine, total residual	daily maximum 0.038 mg/L, tighter	Mar 1, 2027	0.375 mg/L (6 values)	9.87×
DUQUOIN, CITY OF	IL0028517	IL	Sewage plant, major	6 MGD	Coliform, fecal general	daily maximum 400 #/100mL (May–Oct), new	Dec 1, 2027	6075 #/100mL (4 values)	15.2×
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	daily maximum 4.4 mg/L (Mar, Apr, May, Sep, Oct), new	Oct 1, 2028	18.5 mg/L (4 values)	4.2×
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	daily maximum 5.1 mg/L (Jun–Aug), new	Oct 1, 2028	12 mg/L (3 values)	2.35×
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	daily maximum 5.2 mg/L (Jan, Feb, Nov, Dec), new	Oct 1, 2028	10.6 mg/L (4 values)	2.04×
HILLSBORO, CITY OF	IL0029203	IL	Sewage plant, major	3.067 MGD	Phosphorus, total [as P]	monthly average 1 mg/L, new	Dec 1, 2028	3.19 mg/L (11 values)	3.19×
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	daily maximum 8.1 mg/L (Mar, Apr, May, Sep, Oct), new	Jan 1, 2027	7.93 mg/L (5 values)	0.979×
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	daily maximum 11.1 mg/L (Jun–Aug), new	Jan 1, 2027	5.14 mg/L (3 values)	0.463×
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	monthly average 1.6 mg/L (Mar, Apr, May, Sep, Oct), new	Jan 1, 2027	under 3 values	—
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	monthly average 1.5 mg/L (Jun–Aug), new	Jan 1, 2027	under 3 values	—
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	monthly average 3.5 mg/L (Jan, Feb, Nov, Dec), new	Jan 1, 2027	under 3 values	—
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	weekly average 4 mg/L (Mar, Apr, May, Sep, Oct), new	Jan 1, 2027	under 3 values	—
JACKSON GENERATION LLC	IL0080134	IL	Industrial	.46 MGD	Nitrogen, ammonia total [as N]	weekly average 3.8 mg/L (Jun–Aug), new	Jan 1, 2027	under 3 values	—
MORRIS, CITY OF	IL0021113	IL	Sewage plant, major	8.1 MGD	Chlorine, total residual	daily maximum 0.038 mg/L (May–Oct), tighter	Jan 1, 2028	0.03 mg/L (6 values)	0.789×
MORRIS, CITY OF	IL0021113	IL	Sewage plant, major	8.1 MGD	Chlorine, total residual	daily maximum 0.038 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2028	under 3 values	—
CONSTELLATION ENERGY GENERATION LLC	IL0005037	IL	Industrial, major	—	Chlorine, total residual	daily maximum 0.038 mg/L, tighter	Apr 1, 2028	0.02 mg/L (12 values, 12 below detection)	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	daily maximum 1.8 lb/d (Mar, Apr, May, Sep, Oct), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	daily maximum 2.2 lb/d (Jan, Feb, Nov, Dec), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	daily maximum 2.1 lb/d (Jun–Aug), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	monthly average 1.2 mg/L (Mar, Apr, May, Sep, Oct), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	monthly average 0.5 lb/d (Mar, Apr, May, Sep, Oct), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	monthly average 3.2 mg/L (Jan, Feb, Nov, Dec), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	monthly average 1.3 lb/d (Jan, Feb, Nov, Dec), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	monthly average 1.2 mg/L (Jun–Aug), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	monthly average 0.5 lb/d (Jun–Aug), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	weekly average 1.3 lb/d (Mar–Oct), new	Oct 1, 2028	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0070874	IL	Industrial	.0504 MGD	Nitrogen, ammonia total [as N]	weekly average 3.2 mg/L (Mar–Oct), new	Oct 1, 2028	under 3 values	—
HILLSBORO, CITY OF	IL0029203	IL	Sewage plant, major	3.067 MGD	Phosphorus, total [as P]	monthly average 26 lb/d, new	Dec 1, 2028	under 3 values	—
THAYER, VILLAGE OF	IL0059374	IL	Industrial	.32 MGD	Phosphorus, total [as P]	daily maximum 1.7 lb/d, new	Jul 1, 2029	under 3 values	—
PRAIRIE PATH WATER COMPANY	IL0045381	IL	Industrial	.25 MGD	Nitrogen, ammonia total [as N]	daily maximum 3.9 mg/L (Mar, Apr, May, Sep, Oct), tighter	Oct 1, 2029	2.115 mg/L (4 values)	0.542×
PRAIRIE PATH WATER COMPANY	IL0045381	IL	Industrial	.25 MGD	Nitrogen, ammonia total [as N]	daily maximum 8.1 lb/d (Mar, Apr, May, Sep, Oct), tighter	Oct 1, 2029	4.13 lb/d (3 values)	0.51×
PRAIRIE PATH WATER COMPANY	IL0045381	IL	Industrial	.25 MGD	Nitrogen, ammonia total [as N]	daily maximum 10.1 mg/L (Jan, Feb, Nov, Dec), tighter	Oct 1, 2029	0.84 mg/L (4 values)	0.0832×
PRAIRIE PATH WATER COMPANY	IL0045381	IL	Industrial	.25 MGD	Nitrogen, ammonia total [as N]	daily maximum 6.9 mg/L (Jun–Aug), tighter	Oct 1, 2029	0.48 mg/L (3 values)	0.0696×
PRAIRIE PATH WATER COMPANY	IL0045381	IL	Industrial	.25 MGD	Nitrogen, ammonia total [as N]	daily maximum 14 lb/d (Jun–Aug), tighter	Oct 1, 2029	0.21 lb/d (3 values)	0.015×
PRAIRIE PATH WATER COMPANY	IL0045381	IL	Industrial	.25 MGD	Nitrogen, ammonia total [as N]	daily maximum 21 lb/d (Jan, Feb, Nov, Dec), tighter	Oct 1, 2029	under 3 values	—
CHRISTIAN COUNTY WRD	IL0031356	IL	Sewage plant, major	6.125 MGD	Phosphorus, total [as P]	geometric mean 0.5 mg/L, new	Jan 1, 2030	under 3 values	—
EFFINGHAM, CITY OF	IL0028622	IL	Sewage plant, major	9 MGD	Nitrogen, total [as N]	geometric mean 0.5 mg/L, new	Jan 1, 2030	under 3 values	—
FLORA, CITY OF	IL0020273	IL	Sewage plant, major	1.8 MGD	Phosphorus, total [as P]	AGM 0.5 mg/L, new	Jan 1, 2030	under 3 values	—
KEWANEE, CITY OF	IL0029343	IL	Sewage plant, major	5 MGD	Phosphorus, total [as P]	AGM 0.5 mg/L, new	Jan 1, 2030	under 3 values	—
HIGHLAND, CITY OF	IL0029173	IL	Sewage plant, major	4 MGD	Phosphorus, total [as P]	geometric mean 0.5 mg/L, tighter	Jan 1, 2031	under 3 values	—

Each limit is one EPA's ICIS-NPDES file holds on the permit's current version with a begin date after today, enforceable and numeric, either on a parameter the outfall was never limited on (new) or lower than the limit in force (tighter). Today's median is the plant's own reported values for the same outfall, statistic and unit between Oct 1, 2025 and Sep 30, 2026, with how many; none is shown where most were below a detection limit. Read the permit before relying on a value.

Sell to these plants? The list for your states every week, with every plant over a limit on your pollutant, as a spreadsheet, by API and by email when a new one appears: ask for the plant list, or write to info@passage-data.com. What a seller gets.

For programs and AI agents: a state's permits with these limits as JSON at /api/v1/permits?state=IL&upcoming=true, narrowed with &facility_type=potw or &min_flow_mgd=1; the whole list at /dmr/data/upcoming.json; or add https://passage-data.com/mcp as a remote MCP server (tool list_permits). Free, no key. llms.txt

From EPA's ECHO data, not the permit document itself: your permit is the final word. All states

Plants facing new discharge limits — by state and pollutant