St Maries WWTP
Shepherd Rd, Saint Maries, ID 83861 · Benewah County · Publicly Owned Treatment Works
- Average flow
- 2.25 MGD
- Design flow
- 2 MGD
- NPDES permit
- ID0022799
- Expired
- Permit expires
- October 2025
- Population served
- 3,182
- CWNS 2022
St Maries WWTP is a publicly owned wastewater treatment works in Saint Maries, Benewah County, Idaho treating an average of 2.25 million gallons per day against a permitted design capacity of 2 MGD, serving about 3,182 residents. It discharges under NPDES permit ID0022799 (expired), which expires in October 2025, with 36 recorded violations in the last three years. EPA has recorded 6 formal enforcement actions naming the plant, the latest in September 2026.
Treatment technology
One treatment structure or unit process identified at St Maries WWTP.
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See the full treatment train at St Maries WWTP: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 36
- Effluent violations
- 20
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
EPA enforcement history
Federal civil enforcement cases, compliance inspections and informal actions recorded for St Maries WWTP in EPA's ICIS system.
- Formal actions
- 6
- 2 since FY2020
- Penalties assessed
- $36,354
- all cases
- Compliance actions
- $1.9M
- required by EPA orders
- EPA inspections
- 0
- none on record
Latest case · Sep 2026
CITY OF ST MARIES - CAFO (CWA NPDES)
Administrative order · CWA, NPDES Discharge without a Permit · Final Order With Penalty · Penalty $6,534 · Compliance actions $10,000
EPA's description of the case:
“On August 4, 2026, Region 10 issued an administrative order on consent to City of St. Maries for its Wastewater Treatment Plant (WWTP). City of St. Maries failed to reapply for their NPDES Permit and…”
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Source: EPA ECHO, civil enforcement case 10-2026-0220.
Full case history with a free Klarifi account
Every action against St Maries WWTP with dates, milestones, violation types and EPA's complete case summaries, plus inspections and informal actions.
Key contacts
2 verified contacts for St Maries WWTP, with validated emails and direct phone numbers.
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Names, validated emails and direct phone numbers for decision-makers at St Maries WWTP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Idaho
Saint Maries · 14 mi away
—
Fernwood · 16 mi away
0.17 MGD
Worley · 17 mi away
—
Tensed · 20 mi away
—
Smelterville · 23 mi away
2.04 MGD
Smelterville · 23 mi away
0.05 MGD
Princeton · 31 mi away
—
Potlatch · 32 mi away
0.16 MGD
St Maries WWTP: 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 October 26, 2026; facility record last updated September 25, 2026.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Equalization tank · Centrate · all terms