Nitrogen spikes twice in four months at Niwot plant

July 20, 2026Front Range Fans

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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.

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