Table 1. Number and Percent of Major Municipal Sewage Treatment Facilities with Numeric Effluent Limits for Nitrogen (N) and/or Phosphorus (P)

This table presents the total number of individual permitted WWTFs that have nitrogen limits only, phosphorus limits only, or have limits for both pollutants. These data include all individual, non-stormwater NPDES permitted facilities with data in ICIS as of February 2016. (The data include EPA-issued permits and tribal permits. The data only include limits with measuring units that are either mass-based or concentration-based. WWTFs are publicly-owned treatment works (POTWs) with the primary permit standard industrial classification ("SIC") code 4952, and where there is no SIC code, the Facility Type Indicator field is labled "POTW.")

EPA Region	State	Universe of Majors	Nitrogen Only (Number)	Nitrogen Only (Percent)	Phosphorus Only (Number)	Phosphorus Only (Percent)	Both N and P (Number)	Both N and P (Percent)	Any (N or P or Both) (Number)	Any (N or P or Both) (Percent)
10	AK	20	0	0	0	0	0	0	0	0
4	AL	119	19	16	3	3	14	12	36	30
6	AR	78	2	3	9	12	7	9	18	23
9	AS(4)	2	0	0	0	0	0	0	0	0
9	AZ	48	2	4	1	2	3	6	6	13
9	CA	175	68	39	0	0	7	4	75	43
8	CO	91	12	13	6	7	5	5	23	25
1	CT(2)	64	1	2	13	20	0	0	14	22
3	DC	2	0	0	1	50	0	0	1	50
3	DE	8	0	0	0	0	5	63	5	63
4	FL(5)	94	13	14	1	1	51	54	65	69
4	GA	151	0	0	74	49	0	0	74	49
6	GM	0	0	0	0	0	0	0	0	0
9	GU	3	0	0	0	0	0	0	0	0
9	HI	2	1	50	0	0	0	0	1	50
7	IA(3),(6)	96	13	14	1	1	0	0	14	15
10	ID	28	0	0	14	50	1	4	15	54
5	IL	214	0	0	58	27	0	0	58	27
5	IN	133	0	0	58	44	0	0	58	44
7	KS	45	0	0	0	0	0	0	0	0
4	KY	87	0	0	22	25	0	0	22	25
6	LA	105	0	0	0	0	0	0	0	0
1	MA	91	1	1	45	49	8	9	54	59
3	MD	47	1	2	1	2	41	87	43	91
1	ME	61	0	0	5	8	0	0	5	8
5	MI	105	0	0	105	100	0	0	105	100
5	MN	75	0	0	50	67	0	0	50	67
7	MO	123	1	1	8	7	0	0	9	7
9	MP(4)	2	0	0	0	0	2	100	2	100
4	MS	65	0	0	0	0	16	25	16	25
8	MT	21	2	10	0	0	11	52	13	62
4	NC(2)	147	1	1	23	16	4	3	28	19
8	ND(3)	16	0	0	1	6	0	0	1	6
7	NE	30	1	3	0	0	0	0	1	3
1	NH	36	2	6	14	39	0	0	16	44
2	NJ(3),(7)	92	0	0	28	30	7	8	35	38
6	NM	22	2	9	1	5	1	5	4	18
9	NV	7	1	14	1	14	1	14	3	43
2	NY	211	30	14	64	30	5	2	99	47
5	OH	205	0	0	101	49	5	2	106	52
6	OK	69	3	4	2	3	0	0	5	7
10	OR	50	0	0	4	8	0	0	4	8
3	PA	291	0	0	35	12	109	37	144	49
2	PR(4)	33	13	39	1	3	16	48	30	91
1	RI	19	6	32	1	5	5	26	12	63
4	SC	98	0	0	16	16	0	0	16	16
8	SD	20	0	0	0	0	0	0	0	0
4	TN	107	2	2	1	1	15	14	18	17
6	TX(8)	489	3	1	29	6	1	0	33	7
8	UT	29	0	0	2	7	0	0	2	7
3	VA(2)	92	10	11	4	4	40	43	54	59
2	VI(4)	2	0	0	0	0	0	0	0	0
1	VT(3)	0	0	0	0	0	0	0	0	0
10	WA(3)	48	1	2	2	4	0	0	3	6
5	WI	86	0	0	86	100	0	0	86	100
3	WV	50	3	6	2	4	6	12	11	22
8	WY(3)	16	0	0	0	0	0	0	0	0
Total		4,420	214	5	893	20	386	9	1,493	34

Notes:
(1) Note that all permits with limits should also have corresponding monitoring requirements for each parameter that is limited to track compliance.
(2) These states have watershed-based permitting for multiple dischargers for nutrients. These permits/facilities may not be reflected in this table. (VA - approximately 112 WWTFs covered for N & P; NC - approximately 54 WWTF covered for N; and CT - approximately 79 facilities covered for N)
(3) IA, ND, VT, WA, and WY did not have primary SIC codes entered into the Permit Basic Info section of ICIS for most or all of their facilities. NJ has only entered SIC codes for 46 percent of its individual permittees in ICIS.
(4) The following territories and regions are included in these tables: American Samoa (AS), Gulf of Mexico (GM), Guam (GU), Northern Mariana Islands (MP), Puerto Rico (PR), and U.S. Virgin Islands (VI).
(5) Upon review, this state indicated that it uses other monitoring location codes in addition to the ones used for this analysis. [FL]
(6) Iowa is in the process of transitioning to a new NPDES database and is working to ensuring accurate transfer and migration of required data into the EPA ICIS-NPDES data system. This process is expected to be complete by summer 2017.
(7) This state noted that its data are batch-loaded into ICIS, and therefore there are some errors based on the state's records. [NJ]
(8) This state indicated that the data managed to capture 12 permits that are either for stormwater (MS4) or industrial facilities. [TX]

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