NPDES ID: COG591186
X — SNC: Effluent violation (non-monthly average limit)
The facility discharged more of a pollutant than its permit allows, measured over a period other than a monthly average.
This quarter: 2 effluent violations.
Mentions
Nitrogen spikes twice in four months at Niwot plant
The Niwot Sanitation District wastewater plant exceeded its permitted nitrogen discharge limit for the second time this year three days ago, releasing inorganic nitrogen at 45 percent above the allowed threshold. The first violation, earlier this year, ran 123 percent over limit. The pattern is now unmistakable: two exceedances in a single calendar year at a single facility. The timing could hardly be worse. Boulder Creek is running at a fraction of its normal summer flow right now — too shallow to dilute anything that enters it — and the creek is already formally listed as impaired under the Clean Water Act. Excess nitrogen in warm, slow water fuels algal blooms and starves the water column of oxygen, conditions that stress every aquatic insect, fish, and invertebrate that depends on a functioning creek. Yet across the entire permit district, no penalties have been assessed. What this repetition signals is a watershed already struggling to recover facing cumulative stress from the same source, year after year. The cleanup plans that were supposed to restore Boulder Creek to health have been in development for years.
Keep readingViolations
June 30, 2026
Static Renewal 7 Day Chronic Ceriodaphnia dubia
40% over limit
Discharged 60 toxic against a permitted limit of 100 toxic (MN VALUE)
DMR, Limited - Numeric Violation
April 30, 2026
Nitrogen, inorganic total
45% over limit
Discharged 14.5 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, inorganic total
65% over limit
Discharged 16.5 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, inorganic total
122% over limit
Discharged 22.2 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, inorganic total
123% over limit
Discharged 22.3 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (4 months ago)
Last confirmed
September 1, 2026 (4 days ago)