In Maryland, for Nitrogen, ammonia total [as N]: 45 plants hold a permit with a new or tighter discharge limit already written into it, taking effect between Nov 1, 2026 and Oct 1, 2030 (247 limits); 8 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 90 · LA 80 · MS 63 · MD 45 · PA 45 · OH 40 · MI 33 · VA 33 · GA 22 · SC 8 · NE 7 · NY 7 · TX 7 · IN 6 · KS 6 · MO 5 · UT 5 · OR 4 · SD 4 · TN 4 · IL 3 · AR 2 · MN 2 · NJ 2 · NM 2 · CO 1

Plant	Permit	State	Type	Design flow	Parameter	New limit	Effective	Today's median	× limit
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.5 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Aug 1, 2027	1.55 mg/L (6 values)	1.03×
Lakeshore Management, INC	MD0024546	MD	Sewage plant	.1125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1 mg/L (May–Oct), tighter	Sep 1, 2027	3 mg/L (3 values)	3×
Lakeshore Management, INC	MD0024546	MD	Sewage plant	.1125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Sep 1, 2027	2.2 mg/L (4 values)	1.57×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2.3 mg/L (Apr–Oct), tighter	Sep 1, 2027	2.75 mg/L (6 values)	1.2×
Grantsville, Town of	MD0020761	MD	Sewage plant	.6 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2 mg/L (May–Oct), tighter	Jan 1, 2028	21.01 mg/L (5 values)	10.5×
Grantsville, Town of	MD0020761	MD	Sewage plant	.6 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 10 lb/d (May–Oct), tighter	Jan 1, 2028	84.46 lb/d (5 values)	8.45×
Grantsville, Town of	MD0020761	MD	Sewage plant	.6 MGD	Nitrogen, ammonia total [as N]	maximum daily average 35 lb/d (May–Oct), tighter	Jan 1, 2028	134.5 lb/d (5 values)	3.84×
Grantsville, Town of	MD0020761	MD	Sewage plant	.6 MGD	Nitrogen, ammonia total [as N]	maximum daily average 6.9 mg/L (May–Oct), tighter	Jan 1, 2028	25.6 mg/L (5 values)	3.71×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.44 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2028	2.015 mg/L (6 values)	4.58×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.06 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2028	0.185 lb/d (6 values)	3.08×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.27 mg/L (May–Oct), tighter	Nov 1, 2028	0.82 mg/L (3 values)	3.04×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.03 lb/d (May–Oct), tighter	Nov 1, 2028	0.08 lb/d (3 values)	2.67×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 1.1 mg/L (May–Oct), tighter	Nov 1, 2028	2.84 mg/L (3 values)	2.58×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 2.01 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2028	4.945 mg/L (6 values)	2.46×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.13 lb/d (May–Oct), tighter	Nov 1, 2028	0.26 lb/d (3 values)	2×
Legacy Enterprises LLC	MD0057487	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.25 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2028	0.455 lb/d (6 values)	1.82×
LANDSMAN, LLC.	MD0023272	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.3 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2028	1.63 mg/L (6 values)	1.25×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.62 mg/L (May–Oct), tighter	Jan 1, 2029	1.096 mg/L (5 values)	1.77×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.5 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2029	1.521 mg/L (6 values)	1.01×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1 mg/L (May–Oct), tighter	Jun 1, 2030	12.59 mg/L (6 values)	12.6×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 3.2 lb/d (May–Oct), tighter	Jun 1, 2030	15.37 lb/d (6 values)	4.8×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum daily average 4.5 mg/L (May–Oct), tighter	Jun 1, 2030	12.88 mg/L (4 values)	2.86×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum daily average 14 lb/d (May–Oct), tighter	Jun 1, 2030	15.94 lb/d (4 values)	1.14×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.4 mg/L (May–Oct), tighter	Oct 1, 2030	12.59 mg/L (6 values)	31.5×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.4 mg/L (May–Oct), tighter	Oct 1, 2030	12.88 mg/L (4 values)	9.2×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.8 lb/d (May–Oct), tighter	Oct 1, 2030	15.38 lb/d (6 values)	8.54×
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum daily average 6.2 lb/d (May–Oct), tighter	Oct 1, 2030	15.94 lb/d (4 values)	2.57×
SOUTHERN CARROLL H.S. WWTP	MD0024589	MD	Sewage plant	—	Nitrogen, ammonia total [as N]	maximum monthly average 3.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2026	3.1 mg/L (6 values)	0.912×
Homestead Mobile Estates WWTP	MD0024961	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.5 mg/L (May–Oct), tighter	Nov 1, 2026	0.45 mg/L (5 values)	0.3×
Homestead Mobile Estates WWTP	MD0024961	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 2.7 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2026	0.45 mg/L (6 values)	0.167×
SOUTHERN CARROLL H.S. WWTP	MD0024589	MD	Sewage plant	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.4 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2026	0.195 lb/d (6 values)	0.139×
Homestead Mobile Estates WWTP	MD0024961	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.5 lb/d (May–Oct), tighter	Nov 1, 2026	0.041 lb/d (5 values)	0.082×
SOUTHERN CARROLL H.S. WWTP	MD0024589	MD	Sewage plant	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.5 mg/L (May–Oct), tighter	Nov 1, 2026	0.1 mg/L (5 values)	0.0667×
Homestead Mobile Estates WWTP	MD0024961	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.89 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Nov 1, 2026	0.056 lb/d (6 values)	0.0629×
Homestead Mobile Estates WWTP	MD0024961	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 10.3 mg/L (May–Oct), tighter	Nov 1, 2026	0.45 mg/L (5 values)	0.0437×
SOUTHERN CARROLL H.S. WWTP	MD0024589	MD	Sewage plant	—	Nitrogen, ammonia total [as N]	maximum daily average 7.1 mg/L (May–Oct), tighter	Nov 1, 2026	0.2 mg/L (5 values)	0.0282×
SOUTHERN CARROLL H.S. WWTP	MD0024589	MD	Sewage plant	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.63 lb/d (May–Oct), tighter	Nov 1, 2026	0 lb/d (5 values)	0×
SOUTHERN CARROLL H.S. WWTP	MD0024589	MD	Sewage plant	—	Nitrogen, ammonia total [as N]	maximum daily average 3 lb/d (May–Oct), tighter	Nov 1, 2026	0 lb/d (5 values)	0×
Cecil County Dept. of Public Works	MD0052027	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1 mg/L (May–Oct), tighter	Dec 1, 2026	0.11 mg/L (5 values)	0.11×
Cecil County Dept. of Public Works	MD0052027	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 16.7 lb/d (May–Oct), tighter	Dec 1, 2026	1.25 lb/d (5 values)	0.0749×
Cecil County Dept. of Public Works	MD0052027	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum daily average 4.6 mg/L (May–Oct), tighter	Dec 1, 2026	0.18 mg/L (5 values)	0.0391×
Cecil County Dept. of Public Works	MD0052027	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum daily average 76.7 lb/d (May–Oct), tighter	Dec 1, 2026	2.11 lb/d (5 values)	0.0275×
Cecil County Dept. of Public Works	MD0052027	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 65 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2026	1 lb/d (6 values)	0.0154×
Cecil County Dept. of Public Works	MD0052027	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 3.9 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2026	0.025 mg/L (6 values)	0.00641×
HIGHLAND VIEW ACADEMY, INC.	MD0024627	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 2.2 mg/L (May–Oct), tighter	Dec 1, 2026	0 mg/L (5 values)	0×
HIGHLAND VIEW ACADEMY, INC.	MD0024627	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.55 lb/d (May–Oct), tighter	Dec 1, 2026	0 lb/d (5 values)	0×
ROCKY GAP STATE PARK WWTP	MD0051667	MD	Industrial	.08 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.2 mg/L (May–Oct), tighter	Dec 1, 2026	0 mg/L (5 values)	0×
ROCKY GAP STATE PARK WWTP	MD0051667	MD	Industrial	.08 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.8 lb/d (May–Oct), tighter	Dec 1, 2026	0 lb/d (5 values)	0×
ROCKY GAP STATE PARK WWTP	MD0051667	MD	Industrial	.08 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 3.8 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2026	0 mg/L (6 values)	0×
ROCKY GAP STATE PARK WWTP	MD0051667	MD	Industrial	.08 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 4.8 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2026	0 lb/d (6 values)	0×
NAVAL RESEARCH LABORATORY	MD0020168	MD	Federal	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.7 mg/L (May–Oct), tighter	Jan 1, 2027	0.5 mg/L (4 values)	0.714×
NAVAL RESEARCH LABORATORY	MD0020168	MD	Federal	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2027	0.5 mg/L (6 values)	0.312×
NAVAL RESEARCH LABORATORY	MD0020168	MD	Federal	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.8 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2027	0.065 lb/d (6 values)	0.0813×
NAVAL RESEARCH LABORATORY	MD0020168	MD	Federal	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.4 lb/d (May–Oct), tighter	Jan 1, 2027	0.02 lb/d (3 values)	0.05×
Town of Boonsboro	MD0020231	MD	Sewage plant	.46 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.1 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2027	0.05 mg/L (6 values)	0.0238×
Town of Boonsboro	MD0020231	MD	Sewage plant	.46 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 9.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2027	0.1 lb/d (6 values)	0.0108×
Town of Boonsboro	MD0020231	MD	Sewage plant	.46 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 4.8 lb/d (May–Oct), tighter	Jan 1, 2027	0 lb/d (5 values)	0×
Town of Boonsboro	MD0020231	MD	Sewage plant	.46 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.1 mg/L (May–Oct), tighter	Jan 1, 2027	0 mg/L (5 values)	0×
Town of Boonsboro	MD0020231	MD	Sewage plant	.46 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5.9 mg/L (May–Oct), tighter	Jan 1, 2027	0 mg/L (5 values)	0×
Town of Boonsboro	MD0020231	MD	Sewage plant	.46 MGD	Nitrogen, ammonia total [as N]	maximum daily average 26.1 lb/d (May–Oct), tighter	Jan 1, 2027	0 lb/d (5 values)	0×
Calvert County Board of Education	MD0052167	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.6 mg/L (May–Oct), tighter	Feb 1, 2027	0.7 mg/L (5 values)	0.437×
Calvert County Board of Education	MD0052167	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.33 lb/d (May–Oct), tighter	Feb 1, 2027	0.08 lb/d (5 values)	0.242×
Maryland Management Company, Inc.	MD0022926	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.74 mg/L (May–Oct), tighter	Feb 1, 2027	0.1 mg/L (5 values)	0.135×
Maryland Management Company, Inc.	MD0022926	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Feb 1, 2027	0.1 mg/L (6 values)	0.0714×
Maryland Management Company, Inc.	MD0022926	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.09 lb/d (May–Oct), tighter	Feb 1, 2027	0.005004 lb/d (5 values)	0.0556×
Maryland Management Company, Inc.	MD0022926	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum daily average 3.1 mg/L (May–Oct), tighter	Feb 1, 2027	0.1 mg/L (5 values)	0.0323×
Maryland Management Company, Inc.	MD0022926	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.16 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Feb 1, 2027	0.003649 lb/d (6 values)	0.0228×
Maryland Management Company, Inc.	MD0022926	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum daily average 7 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Feb 1, 2027	0.1 mg/L (6 values)	0.0143×
MYERSVILLE WWTP	MD0020699	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Mar 1, 2027	0.05 mg/L (6 values)	0.025×
MYERSVILLE WWTP	MD0020699	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 5 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Mar 1, 2027	0.05 lb/d (6 values)	0.01×
MYERSVILLE WWTP	MD0020699	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2 lb/d (May–Oct), tighter	Mar 1, 2027	0 lb/d (5 values)	0×
MYERSVILLE WWTP	MD0020699	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.8 mg/L (May–Oct), tighter	Mar 1, 2027	0 mg/L (5 values)	0×
MYERSVILLE WWTP	MD0020699	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum daily average 8.8 lb/d (May–Oct), tighter	Mar 1, 2027	0 lb/d (5 values)	0×
MYERSVILLE WWTP	MD0020699	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum daily average 3.5 mg/L (May–Oct), tighter	Mar 1, 2027	0 mg/L (5 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.5 lb/d (May–Sep), tighter	Apr 1, 2027	0 lb/d (4 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.2 mg/L (May–Sep), tighter	Apr 1, 2027	0 mg/L (4 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.5 mg/L (Jan, Feb, Mar, Apr, Oct, Nov, Dec), tighter	Apr 1, 2027	0 mg/L (7 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.62 lb/d (Jan, Feb, Mar, Apr, Oct, Nov, Dec), tighter	Apr 1, 2027	0 lb/d (7 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum daily average 8 mg/L (May–Sep), tighter	Apr 1, 2027	0 mg/L (4 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum daily average 3.3 lb/d (May–Sep), tighter	Apr 1, 2027	0 lb/d (4 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum daily average 11.4 mg/L (Jan, Feb, Mar, Apr, Oct, Nov, Dec), tighter	Apr 1, 2027	0 mg/L (7 values)	0×
SHA - Maryland Department of Transportation	MD0023680	MD	Sewage plant	.028 MGD	Nitrogen, ammonia total [as N]	maximum daily average 4.8 lb/d (Jan, Feb, Mar, Apr, Oct, Nov, Dec), tighter	Apr 1, 2027	0 lb/d (7 values)	0×
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.6 mg/L (May–Oct), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.1 lb/d (May–Oct), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.8 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2.5 mg/L (May–Oct), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.42 lb/d (May–Oct), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum daily average 7.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Apr 1, 2027	under 3 values	—
SOUTHERN MD. PRE-RELEASE UNIT	MD0023914	MD	Industrial	.02 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Apr 1, 2027	under 3 values	—
City of Hagerstown - Water and Sewer Department	MD0021776	MD	Sewage plant, major	10.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.6 mg/L (May–Oct), tighter	Jun 1, 2027	0.2 mg/L (3 values)	0.125×
City of Hagerstown - Water and Sewer Department	MD0021776	MD	Sewage plant, major	10.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 107 lb/d (May–Oct), tighter	Jun 1, 2027	12 lb/d (3 values)	0.112×
Washington County Department of Water Quality	MD0063509	MD	Sewage plant, major	4.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.3 mg/L (May–Oct), tighter	Jun 1, 2027	0.1 mg/L (5 values)	0.0435×
City of Hagerstown - Water and Sewer Department	MD0021776	MD	Sewage plant, major	10.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 3.2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2027	0.1 mg/L (6 values)	0.0312×
Washington County Department of Water Quality	MD0063509	MD	Sewage plant, major	4.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 86 lb/d (May–Oct), tighter	Jun 1, 2027	2 lb/d (5 values)	0.0233×
Washington County Department of Water Quality	MD0063509	MD	Sewage plant, major	4.1 MGD	Nitrogen, ammonia total [as N]	maximum daily average 8.6 mg/L (May–Oct), tighter	Jun 1, 2027	0.2 mg/L (5 values)	0.0233×
City of Hagerstown - Water and Sewer Department	MD0021776	MD	Sewage plant, major	10.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 214 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2027	4 lb/d (6 values)	0.0187×
Washington County Department of Water Quality	MD0063509	MD	Sewage plant, major	4.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 5.7 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2027	0.1 mg/L (6 values)	0.0175×
Washington County Department of Water Quality	MD0063509	MD	Sewage plant, major	4.1 MGD	Nitrogen, ammonia total [as N]	maximum daily average 324 lb/d (May–Oct), tighter	Jun 1, 2027	3.5 lb/d (5 values)	0.0108×
Washington County Department of Water Quality	MD0063509	MD	Sewage plant, major	4.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 214 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2027	2.1 lb/d (6 values)	0.00981×
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.02 lb/d (May–Oct), tighter	Jun 1, 2027	0.001 lb/d (5 values, 5 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.32 mg/L (May–Oct), tighter	Jun 1, 2027	0.11 mg/L (5 values, 5 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.03 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2027	0.001 lb/d (7 values, 7 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.62 mg/L (Jan, Feb, Mar, Nov, Dec), tighter	Jun 1, 2027	0.12 mg/L (5 values, 5 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.07 lb/d (May–Oct), tighter	Jun 1, 2027	0.002 lb/d (5 values, 5 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 1.3 mg/L (May–Oct), tighter	Jun 1, 2027	0.2 mg/L (5 values, 5 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 3 mg/L (Jan, Feb, Mar, Nov, Dec), tighter	Jun 1, 2027	0.18 mg/L (5 values, 5 below detection)	—
HAPPY HILLS CAMPGROUND WWTP	MD0065757	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.17 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2027	0.002 lb/d (7 values, 7 below detection)	—
FREDERICK COUNTY DIV. OF UTILITIES AND SOLID WASTE	MD0021822	MD	Sewage plant, major	7 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 6.3 mg/L (Jan, Feb, Mar, Nov, Dec), tighter	Jul 1, 2027	0.013 mg/L (3 values)	0.00206×
FREDERICK COUNTY DIV. OF UTILITIES AND SOLID WASTE	MD0021822	MD	Sewage plant, major	7 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 788 lb/d (Jan, Feb, Mar, Nov, Dec), tighter	Jul 1, 2027	1 lb/d (3 values)	0.00127×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 11 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Aug 1, 2027	7.2 lb/d (6 values)	0.655×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum daily average 8 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Aug 1, 2027	4.05 mg/L (6 values)	0.506×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum daily average 57 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Aug 1, 2027	20 lb/d (6 values)	0.351×
WESTMINSTER WWTP	MD0021831	MD	Sewage plant, major	5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Aug 1, 2027	0.3 mg/L (6 values)	0.15×
WESTMINSTER WWTP	MD0021831	MD	Sewage plant, major	5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.4 mg/L (May–Oct), tighter	Aug 1, 2027	0.18 mg/L (5 values)	0.129×
WESTMINSTER WWTP	MD0021831	MD	Sewage plant, major	5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 83 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Aug 1, 2027	9.53 lb/d (6 values)	0.115×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1 mg/L (May–Oct), tighter	Aug 1, 2027	0.1 mg/L (5 values)	0.1×
WESTMINSTER WWTP	MD0021831	MD	Sewage plant, major	5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 58 lb/d (May–Oct), tighter	Aug 1, 2027	5.12 lb/d (5 values)	0.0883×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 7.1 lb/d (May–Oct), tighter	Aug 1, 2027	0.3 lb/d (5 values)	0.0423×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum daily average 49.7 lb/d (May–Oct), tighter	Aug 1, 2027	0.8 lb/d (5 values)	0.0161×
TOWN OF DELMAR	MD0020532	MD	Sewage plant	.85 MGD	Nitrogen, ammonia total [as N]	maximum daily average 7 mg/L (May–Oct), tighter	Aug 1, 2027	0.1 mg/L (5 values)	0.0143×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.6 mg/L (Apr–Oct), tighter	Sep 1, 2027	0.55 mg/L (6 values)	0.917×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum daily average 38 lb/d (Apr–Oct), tighter	Sep 1, 2027	21.25 lb/d (6 values)	0.559×
Lakeshore Management, INC	MD0024546	MD	Sewage plant	.1125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.94 lb/d (May–Oct), tighter	Sep 1, 2027	0.5 lb/d (3 values)	0.532×
The Mayor and Commissioners of Perryville	MD0020613	MD	Sewage plant, major	1.65 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.1 mg/L (May–Oct), tighter	Sep 1, 2027	0.55 mg/L (5 values)	0.5×
Lakeshore Management, INC	MD0024546	MD	Sewage plant	.1125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Sep 1, 2027	0.55 lb/d (5 values, 1 below detection)	0.423×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 10 lb/d (Apr–Oct), tighter	Sep 1, 2027	3.95 lb/d (6 values)	0.395×
The Mayor and Commissioners of Perryville	MD0020613	MD	Sewage plant, major	1.65 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 15 lb/d (May–Oct), tighter	Sep 1, 2027	4 lb/d (5 values)	0.267×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1 mg/L (Jan, Feb, Mar, Nov, Dec), tighter	Sep 1, 2027	0.2 mg/L (5 values)	0.2×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum daily average 4.4 mg/L (Jan, Feb, Mar, Nov, Dec), tighter	Sep 1, 2027	0.6 mg/L (5 values)	0.136×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 17 lb/d (Jan, Feb, Mar, Nov, Dec), tighter	Sep 1, 2027	1.7 lb/d (5 values)	0.1×
Maryland Environmental Service (MES)	MD0063207	MD	Sewage plant, major	2 MGD	Nitrogen, ammonia total [as N]	maximum daily average 73 lb/d (Jan, Feb, Mar, Nov, Dec), tighter	Sep 1, 2027	4.4 lb/d (5 values)	0.0603×
Town of Pittsville Commissioners	MD0060348	MD	Industrial	.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.3 lb/d (May–Sep), tighter	Oct 1, 2027	under 3 values	—
Town of Pittsville Commissioners	MD0060348	MD	Industrial	.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.4 mg/L (May–Sep), tighter	Oct 1, 2027	under 3 values	—
Town of Pittsville Commissioners	MD0060348	MD	Industrial	.1 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5.4 lb/d (May–Sep), tighter	Oct 1, 2027	under 3 values	—
Town of Pittsville Commissioners	MD0060348	MD	Industrial	.1 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5.6 mg/L (May–Sep), tighter	Oct 1, 2027	under 3 values	—
TANEYTOWN WWTP	MD0020672	MD	Sewage plant, major	1.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.3 mg/L (May–Oct), tighter	Dec 1, 2027	0.6 mg/L (5 values)	0.462×
TANEYTOWN WWTP	MD0020672	MD	Sewage plant, major	1.1 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 12 lb/d (May–Oct), tighter	Dec 1, 2027	3 lb/d (5 values)	0.25×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 17 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	2.465 lb/d (6 values)	0.145×
The City of Frederick	MD0021610	MD	Sewage plant, major	8 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.74 mg/L (May–Oct), tighter	Dec 1, 2027	0.2 mg/L (5 values)	0.115×
The City of Frederick	MD0021610	MD	Sewage plant, major	8 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 116 lb/d (May–Oct), tighter	Dec 1, 2027	9.5 lb/d (5 values)	0.0819×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	0.125 mg/L (6 values)	0.0625×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum daily average 9.2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	0.485 mg/L (6 values)	0.0527×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.6 mg/L (May–Oct), tighter	Dec 1, 2027	0.02 mg/L (5 values)	0.0333×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5 lb/d (May–Oct), tighter	Dec 1, 2027	0.1 lb/d (3 values)	0.02×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2 mg/L (May–Oct), tighter	Dec 1, 2027	0.03 mg/L (5 values)	0.015×
THURMONT WWTP	MD0021121	MD	Sewage plant, major	1.13 MGD	Nitrogen, ammonia total [as N]	maximum daily average 77 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	0.725 lb/d (6 values)	0.00942×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.1 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.4 mg/L (May–Oct), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.3 lb/d (May–Oct), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.6 mg/L (May–Oct), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.4 mg/L (May–Oct), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.1 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.3 lb/d (May–Oct), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.6 mg/L (May–Oct), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0069418	MD	Industrial	.05 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
The City of Frederick	MD0021610	MD	Sewage plant, major	8 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 398 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
The City of Frederick	MD0021610	MD	Sewage plant, major	8 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 5.98 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Dec 1, 2027	under 3 values	—
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.5 mg/L (May–Oct), tighter	Feb 1, 2028	0.5 mg/L (5 values)	1×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Feb 1, 2028	0.9 mg/L (6 values)	0.643×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5.9 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Feb 1, 2028	2.95 mg/L (6 values)	0.5×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2.2 mg/L (May–Oct), tighter	Feb 1, 2028	0.5 mg/L (5 values)	0.227×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 9.2 lb/d (May–Oct), tighter	Feb 1, 2028	2 lb/d (5 values)	0.217×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 26 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Feb 1, 2028	3.05 lb/d (6 values)	0.117×
Cinnamon Woods Waste Water Treatment Plant	MD0069949	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 5.2 mg/L (May–Oct), tighter	Feb 1, 2028	0.45 mg/L (5 values)	0.0865×
GARRETT COUNTY SANITARY DISTRICT, INC.	MD0054348	MD	Sewage plant, major	1.5 MGD	Nitrogen, ammonia total [as N]	maximum daily average 40 lb/d (May–Oct), tighter	Feb 1, 2028	2.6 lb/d (5 values)	0.065×
Cinnamon Woods Waste Water Treatment Plant	MD0069949	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.95 lb/d (May–Oct), tighter	Feb 1, 2028	0.017 lb/d (5 values)	0.0179×
KENNEDYVILLE WWTP	MD0052671	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.2 lb/d (May–Oct), tighter	Feb 1, 2028	under 3 values	—
KENNEDYVILLE WWTP	MD0052671	MD	Sewage plant	.03 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.3 mg/L (May–Oct), tighter	Feb 1, 2028	under 3 values	—
Frederick County Division of Utilities and Solid Waste Management	MD0020737	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.39 mg/L (May–Oct), tighter	Mar 1, 2028	0.2 mg/L (6 values)	0.513×
Frederick County Division of Utilities and Solid Waste Management	MD0020737	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.75 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Mar 1, 2028	0.3 mg/L (5 values)	0.4×
Frederick County Division of Utilities and Solid Waste Management	MD0020737	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.6 mg/L (May–Oct), tighter	Mar 1, 2028	0.6 mg/L (6 values)	0.375×
Frederick County Division of Utilities and Solid Waste Management	MD0020737	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.9 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Mar 1, 2028	0.5 lb/d (5 values)	0.263×
BEL ALTON WWTP	MD0050334	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.5 mg/L (May–Oct), tighter	Mar 1, 2028	0.13 mg/L (5 values)	0.26×
Frederick County Division of Utilities and Solid Waste Management	MD0020737	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.98 lb/d (May–Oct), tighter	Mar 1, 2028	0.2 lb/d (6 values)	0.204×
Frederick County Division of Utilities and Solid Waste Management	MD0020737	MD	Sewage plant	.3 MGD	Nitrogen, ammonia total [as N]	maximum daily average 4.1 lb/d (May–Oct), tighter	Mar 1, 2028	0.75 lb/d (6 values)	0.183×
BEL ALTON WWTP	MD0050334	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.13 lb/d (May–Oct), tighter	Mar 1, 2028	0.008 lb/d (5 values)	0.0615×
Cecil County Department of Public Works	MD0052825	MD	Sewage plant	.25 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.4 mg/L (May–Oct), tighter	Apr 1, 2028	0.035 mg/L (4 values)	0.0875×
Cecil County Department of Public Works	MD0052825	MD	Sewage plant	.25 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.6 mg/L (May–Oct), tighter	Apr 1, 2028	0.13 mg/L (4 values)	0.0813×
Cecil County Department of Public Works	MD0052825	MD	Sewage plant	.25 MGD	Nitrogen, ammonia total [as N]	maximum daily average 3.4 lb/d (May–Oct), tighter	Apr 1, 2028	0.135 lb/d (4 values)	0.0397×
Cecil County Department of Public Works	MD0052825	MD	Sewage plant	.25 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.8 lb/d (May–Oct), tighter	Apr 1, 2028	0.025 lb/d (4 values)	0.0312×
Cecil County Department of Public Works	MD0052825	MD	Sewage plant	.25 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Apr 1, 2028	0.03 mg/L (5 values)	0.025×
Cecil County Department of Public Works	MD0052825	MD	Sewage plant	.25 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.6 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Apr 1, 2028	0.02 lb/d (5 values)	0.00769×
BALTIMORE COUNTY DPW, UITL. DIV.	MD0022713	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 4.6 mg/L (May–Oct), tighter	Apr 1, 2028	under 3 values	—
Harford County Department of Public Works (Spring Meadows WWTP)	MD0024953	MD	Sewage plant	.01 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 7.6 mg/L (May–Oct), tighter	Apr 1, 2028	under 3 values	—
Harford County Department of Public Works (Spring Meadows WWTP)	MD0024953	MD	Sewage plant	.01 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.63 lb/d (May–Oct), tighter	Apr 1, 2028	under 3 values	—
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2028	0.135 mg/L (6 values)	0.0241×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum daily average 9.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2028	0.1125 lb/d (6 values)	0.0121×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 5.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2028	0.035 mg/L (6 values)	0.00648×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 9 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2028	0.0415 lb/d (6 values)	0.00461×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 1.7 mg/L (May–Oct), tighter	May 1, 2028	0 mg/L (5 values)	0×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.8 lb/d (May–Oct), tighter	May 1, 2028	0 lb/d (5 values)	0×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2.3 mg/L (May–Oct), tighter	May 1, 2028	0 mg/L (5 values)	0×
Town of Queenstown	MD0023370	MD	Sewage plant	.09 MGD	Nitrogen, ammonia total [as N]	maximum daily average 3.8 lb/d (May–Oct), tighter	May 1, 2028	0 lb/d (5 values)	0×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.32 mg/L (Jun–Sep), tighter	Sep 1, 2028	0.11 mg/L (3 values)	0.344×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.03 lb/d (Jun–Sep), tighter	Sep 1, 2028	0.01 lb/d (3 values)	0.333×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.3 mg/L (Jun–Sep), tighter	Sep 1, 2028	0.24 mg/L (3 values)	0.185×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.14 lb/d (Jun–Sep), tighter	Sep 1, 2028	0.01 lb/d (3 values)	0.0714×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum daily average 8.7 mg/L (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec), tighter	Sep 1, 2028	0.165 mg/L (8 values)	0.019×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 4.1 mg/L (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec), tighter	Sep 1, 2028	0.065 mg/L (8 values)	0.0159×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.91 lb/d (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec), tighter	Sep 1, 2028	0.005 lb/d (8 values)	0.00549×
Maryland Environmental Service	MD0062821	MD	Sewage plant	.0125 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.43 lb/d (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec), tighter	Sep 1, 2028	0 lb/d (8 values)	0×
LANDSMAN, LLC.	MD0023272	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.11 lb/d (May–Oct), tighter	Nov 1, 2028	0.03 lb/d (5 values)	0.273×
LANDSMAN, LLC.	MD0023272	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.7 mg/L (May–Oct), tighter	Nov 1, 2028	0.16 mg/L (5 values)	0.229×
LANDSMAN, LLC.	MD0023272	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 3.2 mg/L (May–Oct), tighter	Nov 1, 2028	0.32 mg/L (5 values)	0.1×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum daily average 3 mg/L (May–Oct), tighter	Jan 1, 2029	1.864 mg/L (5 values)	0.621×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.26 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2029	0.135 lb/d (6 values)	0.519×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.11 lb/d (May–Oct), tighter	Jan 1, 2029	0.05 lb/d (5 values)	0.455×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum daily average 9.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2029	2.763 mg/L (6 values)	0.288×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.53 lb/d (May–Oct), tighter	Jan 1, 2029	0.09 lb/d (5 values)	0.17×
MT. CARMEL WOODS WWTP	MD0053228	MD	Sewage plant	.021 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.7 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jan 1, 2029	0.242 lb/d (6 values)	0.142×
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2029	0.4 mg/L (3 values)	1×
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 2.4 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2029	1 mg/L (3 values)	0.417×
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.04 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2029	0.01 lb/d (3 values)	0.25×
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.25 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	May 1, 2029	0.04 lb/d (3 values)	0.16×
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.03 lb/d (May–Oct), tighter	May 1, 2029	under 3 values	—
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.3 mg/L (May–Oct), tighter	May 1, 2029	under 3 values	—
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.15 lb/d (May–Oct), tighter	May 1, 2029	under 3 values	—
Charles County Board of Education	MD0023451	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 1.4 mg/L (May–Oct), tighter	May 1, 2029	under 3 values	—
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.2 mg/L (May–Oct), tighter	Jun 1, 2029	0.15 mg/L (4 values)	0.75×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.9 mg/L (May–Oct), tighter	Jun 1, 2029	0.6 mg/L (4 values)	0.667×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.5 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2029	0.3 mg/L (3 values)	0.6×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum daily average 2.6 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2029	0.8 mg/L (3 values)	0.308×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum daily average 1.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2029	0.21 lb/d (3 values)	0.162×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.3 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2029	0.03 lb/d (3 values)	0.1×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.1 lb/d (May–Oct), tighter	Jun 1, 2029	0.0065 lb/d (4 values)	0.065×
COLLEGE OF SOUTHERN MARYLAND	MD0052311	MD	Sewage plant	.06 MGD	Nitrogen, ammonia total [as N]	maximum daily average 0.5 lb/d (May–Oct), tighter	Jun 1, 2029	0.02 lb/d (4 values)	0.04×
U.S. Fish & Wildlife Service, Patuxent Research Refuge	MD0065358	MD	Federal	.0067 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.42 lb/d (May–Oct), tighter	Jul 1, 2029	under 3 values	—
U.S. Fish & Wildlife Service, Patuxent Research Refuge	MD0065358	MD	Federal	.0067 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 7.6 mg/L (May–Oct), tighter	Jul 1, 2029	under 3 values	—
U.S. Fish & Wildlife Service, Patuxent Research Refuge	MD0065358	MD	Federal	.0067 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 7.6 mg/L (May–Oct), tighter	Jul 1, 2029	under 3 values	—
U.S. Fish & Wildlife Service, Patuxent Research Refuge	MD0065358	MD	Federal	.0067 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 0.42 lb/d (May–Oct), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.025 lb/d (May–Oct), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.6 mg/L (May–Oct), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 1.2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum monthly average 0.05 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.125 lb/d (May–Oct), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 3 mg/L (May–Oct), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 6.9 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jul 1, 2029	under 3 values	—
VIDHI ALEXANDRIA, LLC	MD0053155	MD	Industrial	—	Nitrogen, ammonia total [as N]	maximum daily average 0.288 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jul 1, 2029	under 3 values	—
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 3.1 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2030	under 3 values	—
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 10 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Jun 1, 2030	under 3 values	—
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 2.2 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Oct 1, 2030	under 3 values	—
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum monthly average 9.7 lb/d (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Oct 1, 2030	under 3 values	—
Town of Hancock	MD0024562	MD	Sewage plant	.38 MGD	Nitrogen, ammonia total [as N]	maximum daily average 5.9 mg/L (Jan, Feb, Mar, Apr, Nov, Dec), tighter	Oct 1, 2030	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=MD&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