NORTH ATTLEBOROUGH W W T P
NPDES ID: MA0101036
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
This quarter: 10 effluent violations.
Violations
June 30, 2026
Nitrogen, ammonia total [as N]
23% over limit
Discharged 1.84 mg/L against a permitted limit of 1.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
53% over limit
Discharged 3.06 mg/L against a permitted limit of 2 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total recoverable
7% over limit
Discharged 0.0106 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
230% over limit
Discharged 0.33 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
46% over limit
Discharged 583 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
May 31, 2026
Copper, total recoverable
32% over limit
Discharged 0.0131 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
17% over limit
Discharged 0.0173 mg/L against a permitted limit of 0.0148 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2026
Copper, total recoverable
9% over limit
Discharged 0.0161 mg/L against a permitted limit of 0.0148 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total recoverable
24% over limit
Discharged 0.0123 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
460% over limit
Discharged 0.56 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Solids, suspended percent removal
47% over limit
Discharged 78 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, total suspended
140% over limit
Discharged 36 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
3% over limit
Discharged 0.0102 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
30% over limit
Discharged 5.98 MGD against a permitted limit of 4.61 MGD (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
20% over limit
Discharged 18 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
344% over limit
Discharged 111 mg/L against a permitted limit of 25 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
30% over limit
Discharged 5.98 MGD against a permitted limit of 4.61 MGD (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
93% over limit
Discharged 58 mg/L against a permitted limit of 30 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
997% over limit
Discharged 329 mg/L against a permitted limit of 30 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
12% over limit
Discharged 28 mg/L against a permitted limit of 25 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
16% over limit
Discharged 0.0172 mg/L against a permitted limit of 0.0148 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
October 31, 2025
Copper, total recoverable
11% over limit
Discharged 0.011 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
510% over limit
Discharged 0.61 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Copper, total recoverable
13% over limit
Discharged 0.0112 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
600% over limit
Discharged 0.7 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
229% over limit
Discharged 1316 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
NOEL Static Renewal 7Day Chronic Ceriodaphnia dubia
94% over limit
Discharged 6 % against a permitted limit of 94 % (DAILY MN)
DMR, Limited - Numeric Violation
July 31, 2025
Phosphorus, total [as P]
50% over limit
Discharged 0.15 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
12% over limit
Discharged 0.0111 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
June 30, 2025
Phosphorus, total [as P]
620% over limit
Discharged 0.72 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
23% over limit
Discharged 245 MPN/100mL against a permitted limit of 200 MPN/100mL (MO GEO)
DMR, Limited - Numeric Violation
Coliform, fecal general
397% over limit
Discharged 1986 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
May 31, 2025
Flow, in conduit or thru treatment plant
10% over limit
Discharged 5.09 MGD against a permitted limit of 4.61 MGD (MO AVG)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
10% over limit
Discharged 5.09 MGD against a permitted limit of 4.61 MGD (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
290% over limit
Discharged 0.39 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
Phosphorus, total [as P]
430% over limit
Discharged 0.53 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2025
Flow, in conduit or thru treatment plant
2% over limit
Discharged 4.71 MGD against a permitted limit of 4.61 MGD (MO AVG)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
2% over limit
Discharged 4.71 MGD against a permitted limit of 4.61 MGD (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Coliform, fecal general
505% over limit
Discharged 2420 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2025
Chlorine, total residual
21% over limit
Discharged 0.023 mg/L against a permitted limit of 0.019 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
27% over limit
Discharged 1.27 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Solids, total suspended
63% over limit
Discharged 49 mg/L against a permitted limit of 30 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
3% over limit
Discharged 31 mg/L against a permitted limit of 30 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Coliform, fecal general
140% over limit
Discharged 960 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2024
Coliform, fecal general
168% over limit
Discharged 1070 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
October 31, 2024
Chlorine, total residual
111% over limit
Discharged 0.04 mg/L against a permitted limit of 0.019 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
12% over limit
Discharged 1.68 mg/L against a permitted limit of 1.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
60% over limit
Discharged 8 mg/L against a permitted limit of 5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
1040% over limit
Discharged 1.14 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
290% over limit
Discharged 39 mg/L against a permitted limit of 10 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
328% over limit
Discharged 1712 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total recoverable
10% over limit
Discharged 0.0109 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
40% over limit
Discharged 14 mg/L against a permitted limit of 10 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
43% over limit
Discharged 10 mg/L against a permitted limit of 7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
127% over limit
Discharged 34 mg/L against a permitted limit of 15 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
September 30, 2024
Solids, total suspended
580% over limit
Discharged 102 mg/L against a permitted limit of 15 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
91% over limit
Discharged 2.87 mg/L against a permitted limit of 1.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
70% over limit
Discharged 1.7 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
177% over limit
Discharged 5.53 mg/L against a permitted limit of 2 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
71% over limit
Discharged 12 mg/L against a permitted limit of 7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
590% over limit
Discharged 0.69 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2024
Solids, total suspended
257% over limit
Discharged 35.7 mg/L against a permitted limit of 10 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
10% over limit
Discharged 1.65 mg/L against a permitted limit of 1.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
270% over limit
Discharged 0.37 mg/L against a permitted limit of 0.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Copper, total recoverable
88% over limit
Discharged 0.0186 mg/L against a permitted limit of 0.0099 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
493% over limit
Discharged 89 mg/L against a permitted limit of 15 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Copper, total recoverable
143% over limit
Discharged 0.036 mg/L against a permitted limit of 0.0148 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
31% over limit
Discharged 9.2 mg/L against a permitted limit of 7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (4 months ago)
Last confirmed
August 15, 2026 (12 hours ago)