Unregulated Contaminant Monitoring Rule (UCMR)

The Environmental Protection Agency (EPA) is authorized by the Safe Drinking Water Act (SDWA) to set, monitor, and enforce national health-based standards for drinking water. Within the SDWA, the EPA is required to issue a list of unregulated contaminants that are to be monitored by public water systems (PWSs).

This rule, known as the Unregulated Contaminant Monitoring Rule (UCMR), is used by the EPA to collect data from PWSs on contaminants that do not have health-based standards set by the SDWA, and are suspected to be in drinking water.

Link to EPA's UCMR page

Why was the UCMR Program developed?

The 1996 Amendments to the SDWA and the amendments by Section 2021 of America’s Water Infrastructure Act of 2018 facilitate for:

A monitoring program for priority unregulated contaminants in drinking water that is revised every five years
Monitoring of all large PWSs in the United States that serve more than 10,000 people
Monitoring of all small PWSs that serve between 3,000 and 10,000 people, and a representative sample of PWSs that serve populations under 3,000 people
Analytical data is stored in the National Contaminant Occurrence Data (NCOD) which can be accessed here

Data collected through the UCMR program is used to support the Administrator’s determination of whether to regulate particular contaminants in the interest of protecting public health.

The Public Health benefits of UCMR.

Collection of the scientifically valid data provides the EPA and other entities with a means to conduct exposure assessments to the contaminants in drinking water for both national and specific geographical populations. In addition to this, the UCMR data is one of the key data sources used by the EPA to inform future regulatory and other risk management decisions for drinking water contaminants.

Definitions

Minimum Reporting Levels (MRLs) are derived from the capability of the analytical method.

Maximum Contaminant Levels (MCLs) are the highest levels of a contaminant that is allowed in drinking water. This is a drinking water regulation enforced by EPA.

Health Advisory Levels are estimated acceptable levels of a contaminant in drinking water based on health effects information. They are not regulations but serve as technical guidance from EPA.

Reference Concentrations are health-based levels above which adverse health effects have been documented. They are not regulations, and not all contaminants have reference concentrations.

Detected Compounds (µg/L, or parts per Billion)

1 microgram per Liter (µg/L), or 1 part per billion (ppb) is the equivalent of a few drops of water in an Olympic-sized swimming pool.

You can find the detected contaminants for each UCMR period below:

UCMR5

UCMR5 requires utilities to monitor and submit data for:

29 per- and polyfluoroalkyl substances (PFAS) known as forever chemicals
- Read more information on PFAS here
Lithium, a soft and silvery-white alkali metal that is commonly used in rechargeable batteries
- Read more about Lithium in drinking water here

Table 1. Contaminants Detected in 2024 UCMR5 Samples

Sample Point ID	Sample Point Name	Sample Collection Date	Analyte Name	Result (µg/L)	Minimum Reporting Limit (µg/L)
EPD	Dalecarlia Connection	7/22/2024	Perfluoropentanoic acid (PFPeA)	0.0044	0.003
EPD	McMillan Connection	7/22/2024	Perfluoropentanoic acid (PFPeA)	0.0047	0.003
EPD	McMillan Connection	7/22/2024	Perfluorohexanoic acid (PFHxA)	0.0031	0.003

UCMR4

UCMR4 requires utilities to monitor and submit data for:

10 cyanotoxins
- Nine cyanotoxins and one cyanotoxin group
20 additional contaminants

The full list of contaminants can be found on EPA's UCMR4 fact sheet here

Table 2. Contaminants Detected in 2018 UCMR4 Samples

Sample Point ID	Sample Point Name	Sample Collection Date	Analyte Name	Result (µg/L)	Minimum Reporting Limit (µg/L)
EPD	Dale 18	2/14/2018	Manganese	1.2	300
EPD	Dale 18	5/14/2018	Manganese	0.88	300
EPD	Dale 18	8/15/2018	Manganese	0.72	300
EPD	Dale 18	11/14/2018	Manganese	0.75	300
1H23	8th St. NE	2/14/2018	HAA5	24	60
1H23	8th St. NE	2/14/2018	HAA6Br	10	NA
1H23	8th St. NE	2/14/2018	HAA9	33	NA
1H23	8th St. NE	5/15/2018	HAA5	35	60
1H23	8th St. NE	5/15/2018	HAA6Br	9.2	NA
1H23	8th St. NE	5/15/2018	HAA9	43	NA
1H23	8th St. NE	8/15/2018	HAA5	64	60
1H23	8th St. NE	8/15/2018	HAA6Br	8.6	NA
1H23	8th St. NE	8/15/2018	HAA9	72	NA
1H23	8th St. NE	11/14/2018	HAA5	35	60
1H23	8th St. NE	11/14/2018	HAA6Br	7.2	NA
1H23	8th St. NE	11/14/2018	HAA9	42	NA
1H9	E. Capital St. NE	2/13/2018	HAA5	22	60
1H9	E. Capital St. NE	2/13/2018	HAA6Br	13	NA
1H9	E. Capital St. NE	2/13/2018	HAA9	34	NA
1H9	E. Capital St. NE	5/15/2018	HAA5	32	60
1H9	E. Capital St. NE	5/15/2018	HAA6Br	9.1	NA
1H9	E. Capital St. NE	5/15/2018	HAA9	41	NA
1H9	E. Capital St. NE	8/15/2018	HAA5	66	60
1H9	E. Capital St. NE	8/15/2018	HAA6Br	8.4	NA
1H9	E. Capital St. NE	8/15/2018	HAA9	74	NA
1H9	E. Capital St. NE	11/14/2018	HAA5	38	60
1H9	E. Capital St. NE	11/14/2018	HAA6Br	7.9	NA
1H9	E. Capital St. NE	11/14/2018	HAA9	46	NA
2H1BKJV	Bunker Hill Rd. NE	2/13/2018	HAA5	22	60
2H1BKJV	Bunker Hill Rd. NE	2/13/2018	HAA6Br	11	NA
2H1BKJV	Bunker Hill Rd. NE	2/13/2018	HAA9	32	NA
2H1BKJV	Bunker Hill Rd. NE	5/15/2018	HAA5	37	60
2H1BKJV	Bunker Hill Rd. NE	5/15/2018	HAA6Br	9.1	NA
2H1BKJV	Bunker Hill Rd. NE	5/15/2018	HAA9	45	NA
2H1BKJV	Bunker Hill Rd. NE	8/15/2018	HAA5	31	60
2H1BKJV	Bunker Hill Rd. NE	8/15/2018	HAA6Br	4	NA
2H1BKJV	Bunker Hill Rd. NE	8/15/2018	HAA9	35	NA
2H1BKJV	Bunker Hill Rd. NE	11/14/2018	HAA5	8	60
2H1BKJV	Bunker Hill Rd. NE	11/14/2018	HAA6Br	1.8	NA
2H1BKJV	Bunker Hill Rd. NE	11/14/2018	HAA9	9	NA
2H27	Rhode Island Ave. NE	2/13/2018	HAA5	20	60
2H27	Rhode Island Ave. NE	2/13/2018	HAA6Br	10	NA
2H27	Rhode Island Ave. NE	2/13/2018	HAA9	30	NA
2H27	Rhode Island Ave. NE	5/15/2018	HAA5	33	60
2H27	Rhode Island Ave. NE	5/15/2018	HAA6Br	9.2	NA
2H27	Rhode Island Ave. NE	5/15/2018	HAA9	42	NA
2H27	Rhode Island Ave. NE	8/15/2018	HAA5	35	60
2H27	Rhode Island Ave. NE	8/15/2018	HAA6Br	4.3	NA
2H27	Rhode Island Ave. NE	8/15/2018	HAA9	39	NA
2H27	Rhode Island Ave. NE	11/14/2018	HAA5	33	60
2H27	Rhode Island Ave. NE	11/14/2018	HAA6Br	6.8	NA
2H27	Rhode Island Ave. NE	11/14/2018	HAA9	40	NA
3H13	Kennedy St. NW	2/13/2018	HAA5	24	60
3H13	Kenndey St. NW	2/13/2018	HAA6Br	8.6	NA
3H13	Kenndey St. NW	2/13/2018	HAA9	32	NA
3H13	Kenndey St. NW	5/15/2018	HAA5	37	60
3H13	Kenndey St. NW	5/15/2018	HAA6Br	9.5	NA
3H13	Kenndey St. NW	5/15/2018	HAA9	46	NA
3H13	Kenndey St. NW	8/14/2018	HAA5	58	60
3H13	Kenndey St. NW	8/14/2018	HAA6Br	9.1	NA
3H13	Kenndey St. NW	8/14/2018	HAA9	68	NA
3H13	Kenndey St. NW	11/14/2018	HAA5	38	60
3H13	Kenndey St. NW	11/14/2018	HAA6Br	7.2	NA
3H13	Kenndey St. NW	11/14/2018	HAA9	46	NA
3H4BKJV	Kalmia Rd. NW	2/14/2018	HAA5	26	60
3H4BKJV	Kalmia Rd. NW	2/14/2018	HAA6Br	9.3	NA
3H4BKJV	Kalmia Rd. NW	2/14/2018	HAA9	35	NA
3H4BKJV	Kalmia Rd. NW	5/15/2018	HAA5	36	60
3H4BKJV	Kalmia Rd. NW	5/15/2018	HAA6Br	9	NA
3H4BKJV	Kalmia Rd. NW	5/15/2018	HAA9	44	NA
3H4BKJV	Kalmia Rd. NW	8/15/2018	HAA5	6	60
3H4BKJV	Kalmia Rd. NW	8/15/2018	HAA6Br	0.5	NA
3H4BKJV	Kalmia Rd. NW	8/15/2018	HAA9	6	NA
3H4BKJV	Kalmia Rd. NW	11/14/2018	HAA5	16	60
3H4BKJV	Kalmia Rd. NW	11/14/2018	HAA6Br	3	NA
3H4BKJV	Kalmia Rd. NW	11/14/2018	HAA9	19	NA
4H8	Broad Branch Rd. NW	2/14/2018	HAA5	28	60
4H8	Broad Branch Rd. NW	2/14/2018	HAA6Br	8.5	NA
4H8	Broad Branch Rd. NW	2/14/2018	HAA9	36	NA
4H8	Broad Branch Rd. NW	5/15/2018	HAA5	36	60
4H8	Broad Branch Rd. NW	5/15/2018	HAA6Br	9.3	NA
4H8	Broad Branch Rd. NW	5/15/2018	HAA9	44	NA
4H8	Broad Branch Rd. NW	8/15/2018	HAA5	51	60
4H8	Broad Branch Rd. NW	8/15/2018	HAA6Br	9.3	NA
4H8	Broad Branch Rd. NW	8/15/2018	HAA9	60	NA
4H8	Broad Branch Rd. NW	11/14/2018	HAA5	32	60
4H8	Broad Branch Rd. NW	11/14/2018	HAA6Br	6.7	NA
4H8	Broad Branch Rd. NW	11/14/2018	HAA9	39	NA
A1H3BKJV	56th St. NE	2/14/2018	HAA5	24	60
A1H3BKJV	56th St. NE	2/14/2018	HAA6Br	11	NA
A1H3BKJV	56th St. NE	2/14/2018	HAA9	34	NA
A1H3BKJV	56th St. NE	5/15/2018	HAA5	38	60
A1H3BKJV	56th St. NE	5/15/2018	HAA6Br	9.4	NA
A1H3BKJV	56th St. NE	5/15/2018	HAA9	47	NA
A1H3BKJV	56th St. NE	8/14/2018	HAA5	40	60
A1H3BKJV	56th St. NE	8/14/2018	HAA6Br	5.4	NA
A1H3BKJV	56th St. NE	8/14/2018	HAA9	45	NA
A1H3BKJV	56th St. NE	11/14/2018	HAA5	14	60
A1H3BKJV	56th St. NE	11/14/2018	HAA6Br	3.3	NA
A1H3BKJV	56th St. NE	11/14/2018	HAA9	17	NA
A1H8	MLK Ave SE	2/14/2018	HAA5	23	60
A1H8	MLK Ave SE	2/14/2018	HAA6Br	11	NA
A1H8	MLK Ave SE	2/14/2018	HAA9	33	NA
A1H8	MLK Ave SE	5/15/2018	HAA5	37	60
A1H8	MLK Ave SE	5/15/2018	HAA6Br	9.5	NA
A1H8	MLK Ave SE	5/15/2018	HAA9	46	NA
A1H8	MLK Ave SE	8/15/2018	HAA5	61	60
A1H8	MLK Ave SE	8/15/2018	HAA6Br	9.1	NA
A1H8	MLK Ave SE	8/15/2018	HAA9	70	NA
A1H8	MLK Ave SE	11/14/2018	HAA5	35	60
A1H8	MLK Ave SE	11/14/2018	HAA6Br	7.2	NA
A1H8	MLK Ave SE	11/14/2018	HAA9	42	NA
L12	Overlook Ave. SW	2/14/2018	HAA5	23	60
L12	Overlook Ave. SW	2/14/2018	HAA6Br	11	NA
L12	Overlook Ave. SW	2/14/2018	HAA9	33	NA
L12	Overlook Ave. SW	5/15/2018	HAA5	36	60
L12	Overlook Ave. SW	5/15/2018	HAA6Br	9.6	NA
L12	Overlook Ave. SW	5/15/2018	HAA9	45	NA
L12	Overlook Ave. SW	8/15/2018	HAA5	62	60
L12	Overlook Ave. SW	8/15/2018	HAA6Br	8.8	NA
L12	Overlook Ave. SW	8/15/2018	HAA9	71	NA
L12	Overlook Ave. SW	11/14/2018	HAA5	34	60
L12	Overlook Ave. SW	11/14/2018	HAA6Br	7.4	NA
L12	Overlook Ave. SW	11/14/2018	HAA9	41	NA
L24DBPR	49th St. NE	2/14/2018	HAA5	33	60
L24DBPR	49th St. NE	2/14/2018	HAA6Br	12	NA
L24DBPR	49th St. NE	2/14/2018	HAA9	43	NA
L24DBPR	49th St. NE	5/15/2018	HAA5	38	60
L24DBPR	49th St. NE	5/15/2018	HAA6Br	9.6	NA
L24DBPR	49th St. NE	5/15/2018	HAA9	47	NA
L24DBPR	49th St. NE	8/15/2018	HAA5	64	60
L24DBPR	49th St. NE	8/15/2018	HAA6Br	8.2	NA
L24DBPR	49th St. NE	8/15/2018	HAA9	73	NA
L24DBPR	49th St. NE	11/14/2018	HAA5	30	60
L24DBPR	49th St. NE	11/14/2018	HAA6Br	6.6	NA
L24DBPR	49th St. NE	11/14/2018	HAA9	37	NA
L4	Water St. SW	2/13/2018	HAA5	24	60
L4	Water St. SW	2/13/2018	HAA6Br	9.7	NA
L4	Water St. SW	2/13/2018	HAA9	33	NA
L4	Water St. SW	5/15/2018	HAA5	35	60
L4	Water St. SW	5/15/2018	HAA6Br	9.4	NA
L4	Water St. SW	5/15/2018	HAA9	44	NA
L4	Water St. SW	8/14/2018	HAA5	57	60
L4	Water St. SW	8/14/2018	HAA6Br	10	NA
L4	Water St. SW	8/14/2018	HAA9	67	NA
L4	Water St. SW	11/14/2018	HAA5	32	60
L4	Water St. SW	11/14/2018	HAA6Br	6.7	NA
L4	Water St. SW	11/14/2018	HAA9	39	NA

UCMR3

UCMR3 requires utilities to monitor and submit data for:

28 chemicals
- The full list can be found on EPA's UCMR3 fact sheet here
2 viruses
- Enterovirus & Norovirus

Table 3. Contaminants detected in 2014 UCMR3 Samples

Sample Point ID	Sample Point Name	Sample Collection Date	Analyte Name	Result (µg/L)	Minimum Reporting Limit (µg/L)
EPD	Dalecarlia Connection	1/1/2014	Chlorate	210	20
EPD	Dalecarlia Connection	4/1/2014	Chlorate	140	20
EPD	Dalecarlia Connection	7/1/2014	Chlorate	430	20
EPD	Dalecarlia Connection	10/1/2014	Chlorate	330	20
EPD	Dalecarlia Connection	7/1/2014	Chromium	0.2	0.2
EPD	Dalecarlia Connection	10/1/2014	Chromium	0.26	0.2
EPD	Dalecarlia Connection	1/1/2014	Chromium-6	0.091	0.03
EPD	Dalecarlia Connection	4/1/2014	Chromium-6	0.092	0.03
EPD	Dalecarlia Connection	7/1/2014	Chromium-6	0.098	0.03
EPD	Dalecarlia Connection	10/1/2014	Chromium-6	0.063	0.03
EPD	Dalecarlia Connection	10/1/2014	Molybdenum	1	1
EPD	Dalecarlia Connection	1/1/2014	Strontium	160	0.3
EPD	Dalecarlia Connection	4/1/2014	Strontium	130	0.3
EPD	Dalecarlia Connection	7/1/2014	Strontium	24	0.3
EPD	Dalecarlia Connection	10/1/2014	Strontium	220	0.3
EPD	Dalecarlia Connection	4/1/2014	Vanadium	0.22	0.2
EPD	Dalecarlia Connection	7/1/2014	Vanadium	1.3	0.2
EPD	Dalecarlia Connection	10/1/2014	Vanadium	0.6	0.2
DS-S1 Dale	Dalecarlia Connection	1/1/2014	Chlorate	200	20
DS-S1 Dale	Dalecarlia Connection	4/1/2014	Chlorate	170	20
DS-S1 Dale	Dalecarlia Connection	7/1/2014	Chlorate	470	20
DS-S1 Dale	Dalecarlia Connection	10/1/2014	Chlorate	340	20
DS-S1 Dale	Dalecarlia Connection	10/1/2014	Chromium	0.31	0.2
DS-S1 Dale	Dalecarlia Connection	1/1/2014	Chromium-6	0.077	0.03
DS-S1 Dale	Dalecarlia Connection	4/1/2014	Chromium-6	0.12	0.03
DS-S1 Dale	Dalecarlia Connection	7/1/2014	Chromium-6	0.1	0.03
DS-S1 Dale	Dalecarlia Connection	10/1/2014	Chromium-6	0.076	0.03
DS-S1 Dale	Dalecarlia Connection	10/1/2014	Molybdenum	1.1	1
DS-S1 Dale	Dalecarlia Connection	1/1/2014	Strontium	140	0.3
DS-S1 Dale	Dalecarlia Connection	4/1/2014	Strontium	120	0.3
DS-S1 Dale	Dalecarlia Connection	7/1/2014	Strontium	210	0.3
DS-S1 Dale	Dalecarlia Connection	10/1/2014	Strontium	230	0.3
DS-S1 Dale	Dalecarlia Connection	4/1/2014	Vanadium	0.2	0.2
DS-S1 Dale	Dalecarlia Connection	7/1/2014	Vanadium	0.85	0.2
DS-S1 Dale	Dalecarlia Connection	10/1/2014	Vanadium	0.57	0.2
EPD	McMillan Connection	1/1/2014	Chlorate	160	20
EPD	McMillan Connection	4/1/2014	Chlorate	120	20
EPD	McMillan Connection	7/1/2014	Chlorate	250	20
EPD	McMillan Connection	10/1/2014	Chlorate	410	20
EPD	McMillan Connection	7/1/2014	Chromium	0.24	0.2
EPD	McMillan Connection	10/1/2014	Chromium	0.36	0.2
EPD	McMillan Connection	1/1/2014	Chromium - 6	0.082	0.03
EPD	McMillan Connection	4/1/2014	Chromium - 7	0.075	0.03
EPD	McMillan Connection	7/1/2014	Chromium - 8	0.1	0.03
EPD	McMillan Connection	10/1/2014	Chromium - 9	0.077	0.03
EPD	McMillan Connection	10/1/2014	Molybdenum	1.2	1
EPD	McMillan Connection	1/1/2014	Strontium	130	0.3
EPD	McMillan Connection	4/1/2014	Strontium	120	0.3
EPD	McMillan Connection	7/1/2014	Strontium	200	0.3
EPD	McMillan Connection	10/1/2014	Strontium	260	0.3
EPD	McMillan Connection	7/1/2014	Vanadium	0.57	0.2
EPD	McMillan Connection	10/1/2014	Vanadium	0.4	0.2
DS-S1 McMillan	McMillan Connection	1/1/2014	Chlorate	160	20
DS-S1 McMillan	McMillan Connection	4/1/2014	Chlorate	120	20
DS-S1 McMillan	McMillan Connection	7/1/2014	Chlorate	250	20
DS-S1 McMillan	McMillan Connection	10/1/2014	Chlorate	410	20
DS-S1 McMillan	McMillan Connection	10/1/2014	Chromium	0.32	0.2
DS-S1 McMillan	McMillan Connection	1/1/2014	Chromium - 6	0.074	0.03
DS-S1 McMillan	McMillan Connection	4/1/2014	Chromium - 7	0.077	0.03
DS-S1 McMillan	McMillan Connection	7/1/2014	Chromium - 8	0.1	0.03
DS-S1 McMillan	McMillan Connection	10/1/2014	Chromium - 9	0.079	0.03
DS-S1 McMillan	McMillan Connection	10/1/2014	Molybdenum	1.2	1
DS-S1 McMillan	McMillan Connection	1/1/2014	Strontium	120	0.3
DS-S1 McMillan	McMillan Connection	4/1/2014	Strontium	120	0.3
DS-S1 McMillan	McMillan Connection	7/1/2014	Strontium	190	0.3
DS-S1 McMillan	McMillan Connection	10/1/2014	Strontium	260	0.3
DS-S1 McMillan	McMillan Connection	7/1/2014	Vanadium	0.55	0.2
DS-S1 McMillan	McMillan Connection	10/1/2014	Vanadium	0.39	0.2

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