Northampton Wastewater Treatment Plant
Northampton, MA · Hampshire County · Publicly Owned Treatment Works
- Average flow
- 3.84 MGD
- Design flow
- 8.65 MGD
- NPDES permit
- MA0101818
- Effective
- Permit expires
- November 2028
- Population served
- 26,565
- CWNS 2022
Northampton Wastewater Treatment Plant is a publicly owned wastewater treatment works in Northampton, Hampshire County, Massachusetts treating an average of 3.84 million gallons per day against a permitted design capacity of 8.65 MGD, serving about 26,565 residents. Treatment on site includes clarifiers, biogas balloons, biological n removal, biosolids mechanical dewatering, biosolids thickening and other unit processes. It discharges under NPDES permit MA0101818 (effective), which expires in November 2028, with 40 recorded violations in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Clarifiers
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Biogas balloons
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Biological N removal
unit processBiosolids Mechanical Dewatering
unit processBiosolids Thickening
unit processChemical Addition, Polymer
unit processDisinfection, chlorine/ chloramine
unit processFlotation
unit processPrimary Clarification or Sedimentation
unit processScreening
unit processSedimentation
unit processUnlock exact unit counts →
Compliance snapshot (last 3 years)
- Total violations
- 40
- Effluent violations
- 11
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Capital improvement projects in Northampton
Northampton's capital improvement plan lists 16 water, sewer and wastewater line items worth $34M starting 2026–2028. The largest budgeted items are shown here.
All water and sewer capital projects in Northampton →
| Project | Budget | Years |
|---|---|---|
| Reservoir Construction | $8,750,000 | 2028–2029 |
| Transmission Main Rehabilitation | $6,500,000 | 2027–2027 |
| Waterline Replacement | $4,500,000 | 2026–2030 |
| Sewer Line Replacement | $3,750,000 | 2026–2030 |
| Main Street Corridor Utility Infrastructure | $3,200,000 | 2026–2026 |
Full project details — scope, funding source, engineering consultant and the decision-makers behind each project — are available in Klarifi, along with similar wastewater capital projects in other cities.
Key contacts
5 verified contacts for Northampton Wastewater Treatment Plant, with validated emails and direct phone numbers.
Unlock 5 verified contacts (2 more than shown)
Names, validated emails and direct phone numbers for decision-makers at Northampton Wastewater Treatment Plant, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Massachusetts
Hadley · 2 mi away
0.34 MGD
Hatfield · 6 mi away
0.14 MGD
Hadley · 7 mi away
3.33 MGD
Holyoke · 8 mi away
5.02 MGD
Sunderland · 10 mi away
0.13 MGD
Huntington · 14 mi away
0.03 MGD
Russell · 14 mi away
0.04 MGD
Woronoco Village · 15 mi away
0.004 MGD
Northampton Wastewater Treatment Plant: frequently asked questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed September 11, 2026; facility record last updated March 6, 2025.