A Bleak Assessment for Rivers
Earlier this week, the Environmental Protection Agency released a study [PDF] which assesses the health of rivers and streams across the country. While the good news is that the National Rivers and Streams Assessment (NRSA) provides important data to monitor river health; the bad news is that more than half of our streams and rivers remain in poor condition.
Some key findings of the assessment include:
- 50% of river and stream miles do not support healthy populations of aquatic life;
- 40% of our river and stream miles have high levels of phosphorus, a nutrient that in high amounts causes algal blooms depleting oxygen in the water thereby making it difficult for aquatic life to survive;
- Excess levels of sediment, which can smother aquatic life by damaging the gills of fishes and invertebrates as well as burying their home and nesting habitats, are reported in 15% of river and stream miles; and
- Over 13,000 river miles were found to have mercury in fish tissue at levels that exceed thresholds protective of human health.
Importantly, the NRSA findings have implications for public health. The large number of river miles with high mercury levels threatens citizens who fish and consume contaminated fish. High levels of fecal bacteria in numerous rivers and streams can cause gastrointestinal illness in swimmers or sickness related to consuming fish and shellfish from contaminated waters. Sources of bacteria are generally wastewater treatment plants, leaking septic systems, stormwater runoff, and sewage discharge.
The NRSA further demonstrates that many of our nation’s rivers and streams suffer from high nutrient pollution which creates algal blooms leading to dead zones in our lakes, estuaries, and oceans. With little oxygen, fish and other aquatic life cannot survive. Furthermore, the assessment findings are consistent with previous reports indicating nutrient pollution as a significant factor in poor stream health.
These findings only serve to highlight the continued need to better address sources of nutrient pollution, particularly polluted runoff, that threaten the health of our rivers and streams. American Rivers is working to advocate for a national stormwater rule that will update and modernize existing stormwater programs to better manage polluted runoff.
The EPA, furthermore, could act on their stream assessment findings by releasing guidance to clarify Clean Water Act protections to all Waters of the US. This guidance would give necessary protections to our small streams and wetlands currently in poor condition.