Postings of the E.coli levels will let you know more about the status of the river. The numbers in the chart below indicate a sample. The duplicates show you that 2 samples taken at the same time from the same location can have a very different measured level. Remember a sample is just that, a sample. At the end of the year the FRWA can calculate a geometric mean. Right now you can see how the numbers change depending on factors such as heavy rain increasing pollutant runoff, etc. Click here to see photos of the sites.

E. coli is not considered safe in drinking water at any levels; however the current standards for recreational use levels of E.coli are posted by the CT DEEP as follows. There are no “designated swimming” areas in the Lower Farmington River. Use this as a guide for understanding the numbers in the chart below.

RECREATION	GEOMETRIC MEAN	SINGLE SAMPLE MAXIMUM
Designated Swimming	less than 126/100ml	235/100ml
Non-designated Swimming	less than 126/100ml	410/100ml
All Other Recreational Uses	less than 126/100ml	576/100ml

2021 E.coli Chart

AVON

Site Number	Stream Name	Collection Date	E.coli colonies/100 mL
TB-A1	Thompson Brook	6/7/2022	7.5
TB-A1	Thompson Brook	6/21/2022	9.8
TB-A1	Thompson Brook	7/12/2022	2
TB-A1	Thompson Brook	7/26/2022	47.1
TB-A1	Thompson Brook	8/9/2022	33.1
TB-A1	Thompson Brook	8/23/2022	12.2

NB-A1	Nod Brook	6/7/2022	58.1
NB-A1	Nod Brook	6/21/2022	110.0
NB-A1	Nod Brook	7/12/2022	79.8
NB-A1	Nod Brook	7/26/2022	461.1
NB-A1	Nod Brook	8/9/2022	275.5
NB-A1	Nod Brook	8/23/2022	218.7

BURLINGTON

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML
BB-B1	Bunnell Brook	6/14/2022	31.8
BB-B1	Bunnell Brook	6/28/2022	36.4
BB-B1	Bunnell Brook	7/19/2022	435.2
BB-B1	Bunnell Brook	8/2/2022	21.6
BB-B1	Bunnell Brook	8/16/2022	12.2
BB-B1	Bunnell Brook

CANTON

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML
CB-C1	Cherry Brook	6/6/2022	53.6
CB-C1	Cherry Brook
CB-C1	Cherry Brook
CB-C1	Cherry Brook
CB-C1	Cherry Brook
CB-C1	Cherry Brook

EAST GRANBY

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML
FR-EG1	Farmington River	6/14/2022	85.5
FR-EG1	Farmington River	6/28/2022	75.4
FR-EG1	Farmington River	7/19/2022	290.9
FR-EG1	Farmington River	8/2/2022	72.3
FR-EG1	Farmington River	8/16/2022	24.3
FR-EG1	Farmington River

FARMINGTON

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML
RO-F1	Roaring Brook	6/14/2022	40.8
RO-F1	Roaring Brook	6/28/2022	60.2
RO-F1	Roaring Brook	7/19/2022	307.6
RO-F1	Roaring Brook	8/2/2022	81.6
RO-F1	Roaring Brook	8/16/2022	67.0
RO-F1	Roaring Brook

FR-F1	Farmington River	6/14/2022	40.8
FR-F1	Farmington River	6/28/2022	32.7
FR-F1	Farmington River	7/19/2022	102.2
FR-F1	Farmington River	8/2/2022	34.5
FR-F1	Farmington River	8/16/2022	24.6
FR-F1	Farmington River

PR-F1	Pequabuck River	6/14/2022	185.0
PR-F1	Pequabuck River	6/28/2022	2419.6
PR-F1	Pequabuck River	7/19/2022	>2419.6
PR-F1	Pequabuck River	8/2/2022	461.1
PR-F1	Pequabuck River	8/16/2022	143.9
PR-F1	Pequabuck River

FR-F2	Farmington River	6/14/2022	91.0
FR-F2	Farmington River	6/28/2022	547.5
FR-F2	Farmington River	7/19/2022	1553.1
FR-F2	Farmington River	8/2/2022	86.0
FR-F2	Farmington River	8/16/2022	18.9
FR-F2	Farmington River

SIMSBURY

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML

MS-S1	Minister Brook	6/7/2022	68.9
MS-S1	Minister Brook	6/21/2022	86.5
MS-S1	Minister Brook	7/12/2022	816.4
MS-S1	Minister Brook	7/26/2022	1553.1
MS-S1	Minister Brook	8/9/2022	517.2
MS-S1	Minister Brook	8/23/2022	517.2

RB-S1	Russell Brook	6/7/2022	146.7
RB-S1	Russell Brook	6/21/2022	224.7
RB-S1	Russell Brook	7/12/2022	920.8
RB-S1	Russell Brook	7/26/2022	76.2
RB-S1	Russell Brook	8/9/2022	579.4
RB-S1	Russell Brook	8/23/2022	187.2

FR-S1	Farmington River	6/7/2022	54.8
FR-S1	Farmington River	6/21/2022	66.3
FR-S1	Farmington River	7/12/2022	16.9
FR-S1	Farmington River	7/26/2022	110.0
FR-S1	Farmington River	8/9/2022	45.2
FR-S1	Farmington River	8/23/2022	42.6

FR-S3	Farmington River	6/7/2022	52.9
FR-S3	Farmington River	6/21/2022	50.4
FR-S3	Farmington River	7/12/2022	52.0
FR-S3	Farmington River	7/26/2022	91.0
FR-S3	Farmington River	8/9/2022	53.6
FR-S3	Farmington River	8/23/2022	27.9

HB-S2	Hop Brook	6/7/2022	248.9
HB-S2	Hop Brook	6/21/2022	62.0
HB-S2	Hop Brook	7/12/2022	35.5
HB-S2	Hop Brook	7/26/2022	224.7
HB-S2	Hop Brook	8/9/2022	261.3
HB-S2	Hop Brook	8/23/2022	71.2

FR-S2	Farmington River	6/7/2022	65.0
FR-S2	Farmington River	6/21/2022	51.2
FR-S2	Farmington River	7/12/2022	83.9
FR-S2	Farmington River	7/26/2022	325.5
FR-S2	Farmington River	8/9/2022	57.3
FR-S2	Farmington River	8/23/2022	18.5

MB-S1	Minnisunk Brook	6/7/2022	29.2
MB-S1	Minnisunk Brook	6/21/2022	22.8
MB-S1	Minnisunk Brook	7/12/2022	13.4
MB-S1	Minnisunk Brook	7/26/2022	3.0
MB-S1	Minnisunk Brook	8/9/2022	27.5
MB-S1	Minnisunk Brook	8/23/2022	31.8
MB-S1	Minnisunk Brook

GRANBY

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML
SB-EB1	East Branch Salmon Brook	6/14/2022	261.3
SB-EB1	East Branch Salmon Brook	6/28/2022	410.6
SB-EB1	East Branch Salmon Brook	7/19/2022	547.5
SB-EB1	East Branch Salmon Brook	8/2/2022	517.2
SB-EB1	East Branch Salmon Brook	8/16/2022	172.5
SB-EB1	East Branch Salmon Brook

SB-2	Salmon Brook	6/14/2022	218.7
SB-2	Salmon Brook	6/28/2022	365.4
SB-2	Salmon Brook	7/19/2022	261.3
SB-2	Salmon Brook	8/2/2022	209.8
SB-2	Salmon Brook	8/16/2022	185.0
SB-2	Salmon Brook

SB-WB3	West Branch Salmon Brook	6/7/2022	260.3
SB-WB3	West Branch Salmon Brook	6/21/2022	64.4
SB-WB3	West Branch Salmon Brook	7/12/2022	58.3
SB-WB3	West Branch Salmon Brook	7/26/2022	90.9
SB-WB3	West Branch Salmon Brook	8/9/2022	161.6
SB-WB3	West Branch Salmon Brook

WINDSOR

Site Number	Stream Name	Collection Date	E.Coli Colonies/100 ML
FR-W1	Farmington River	6/14/2022	60.2
FR-W1	Farmington River	6/28/2022	139.6
FR-W1	Farmington River	7/19/2022	224.7
FR-W1	Farmington River	8/2/2022	579.4
FR-W1	Farmington River	8/16/2022	25.6
FR-W1	Farmington River

PB-W1	Phelps Brook	6/14/2022	161.6
PB-W1	Phelps Brook	6/28/2022	218.7
PB-W1	Phelps Brook	7/19/2022	517.2
PB-W1	Phelps Brook	8/2/2022	81.6
PB-W1	Phelps Brook	8/16/2022	71.2
PB-W1	Phelps Brook

ML-W1	Mill Brook	6/14/2022	261.3
ML-W1	Mill Brook	6/28/2022	387.3
ML-W1	Mill Brook	7/19/2022	2419.6
ML-W1	Mill Brook	8/2/2022	209.8
ML-W1	Mill Brook	8/16/2022	307.6
ML-W1	Mill Brook

FR-W2	Farmington River	6/14/2022	71.2
FR-W2	Farmington River	6/28/2022	206.4
FR-W2	Farmington River	7/19/2022	435.2
FR-W2	Farmington River	8/2/2022	40.2
FR-W2	Farmington River	8/16/2022	29.5
FR-W2	Farmington River
FR-W2	Farmington River

YEARLY GEOMETRIC MEAN

AVON	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
TB-A1	21	294	50	58	80	51	84	11	23	80	19	63	27	42
NB-A1	163	358	90	612	138	209	130	90	119	277	172	318	62	112

BURLINGTON	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
BB-B1	N/A	N/A	N/A	N/A	150	47	39	24	162	364	195	133	23	43

CANTON	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
CB-C1	N/A	355	207	408	332	160	105	56	265	770	437	1454	548	135

EAST GRANBY	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
FR-EG1	N/A	N/A	N/A	N/A	365	169	78	135	74	181	219	293	75	194

FARMINGTON	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
RO-F1	N/A	N/A	102	104	85	88	62	85	192	221	358	147	72	70
FR-F1	28	120	83	55	79	120	62	53	73	60	126	103	40	120
PR-F1	846	1437	352	750	719	697	329	245	642	780	829	676	746	282
FR-F2	141	413	122	179	199	223	159	53	150	204	235	223	133	181

SIMSBURY	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
SB-EB1	567	378	438	234	715	318	177	772	243	501	523	882	344	457
SB-2	N/A	N/A	N/A	N/A	445	313	218	910	178	367	631	643	252	324
MS-S1	90	770	607	1373	30	532	1312	78	118	191	50	617	156	222
RB-S1	190	431	172	415	338	172	568	143	77	167	73	97	89	285
FR-S1	102	447	198	155	165	95	61	151	41	93	63	167	40	68

GRANBY	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
MB-S1	858	3361	67	64	30	35	58	54	258	66	24	58	20	43
SB-WB3	N/A	174	121	133	258	90	95	124	307	125	112	171	116	88
FR-S3	160	379	169	105	200	88	108	92	156	107	61	149	52	71
HB-S1	117	328	277	203	430	398	149	70	347	240	78	285	83	107
FR-S2	226	314	184	110	199	126	87	73	304	47	88	198	44	79

WINDSOR	2007	2008	2009	2010	2011	2012	2013	2014	2015	2016	2017	2018	2019	2021
FR-W1	101	N/A	121	123	213	126	71	52	50	275	244	115	26	142
PB-W1	N/A	N/A	N/A	174	328	156	251	149	287	672	615	577	81	165
ML-W1	N/A	N/A	368	367	529	510	195	290	309	1271	984	824	253	667
FR-W2	N/A	N/A	N/A	N/A	213	126	71	91	74	112	20	112	90	135