West Boise WWTP
11818 Joplin Rd, Garden City, ID 83714 · Ada County · Publicly Owned Treatment Works
- Average flow
- 50.91 MGD
- Design flow
- 24 MGD
- NPDES permit
- ID0023981
- Effective
- Permit expires
- June 2027
- Population served
- 380,979
- CWNS 2022
West Boise WWTP is a publicly owned wastewater treatment works in Garden City, Ada County, Idaho treating an average of 50.91 million gallons per day against a permitted design capacity of 24 MGD, serving about 380,979 residents. It discharges under NPDES permit ID0023981 (effective), which expires in June 2027, with 10 recorded violations in the last three years.
Treatment technology
3 treatment structures and unit processes identified at West Boise WWTP.
Available with a free Klarifi account
See the full treatment train at West Boise WWTP: structures, unit processes and planned upgrades, with exact unit counts.
Compliance snapshot (last 3 years)
- Total violations
- 10
- Effluent violations
- 4
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
2 verified contacts for West Boise WWTP, with validated emails and direct phone numbers.
Unlock 2 verified contacts
Names, validated emails and direct phone numbers for decision-makers at West Boise WWTP, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Idaho
Star · 8 mi away
1.52 MGD
Meridian · 10 mi away
1.3 MGD
Nampa · 13 mi away
10.69 MGD
Emmett · 17 mi away
1.68 MGD
Horseshoe Bend · 18 mi away
0.08 MGD
Greenleaf · 24 mi away
0.06 MGD
Notus · 24 mi away
0.06 MGD
Marsing · 25 mi away
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West Boise 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 August 19, 2026.
Wastewater terms: POTW · MGD · NPDES permit · Inflow and infiltration · Anaerobic digester · Lift station · all terms