(December 4, 2018) - A recent US Geological Survey (USGS) report published in a peer-reviewed journal, Science of the Total Environment, analyzes trends in nutrient and sediment loading from rivers and streams that flow into coastal waters.
The study found a trend or pattern from 2002 to 2012 in urban areas, where it was more common to find reductions in nitrogen loading as compared to phosphorus loading. The study observed that this correlation could be a reflection of how clean water utilities strive to meet heightened regulatory requirements. When compared to agricultural areas, the study found a less consistent trend pattern.
The study also found the nitrogen to phosphorus ratio (N:P ratio) is higher now than pre-1979 levels, meaning that the streams and rivers assessed are phosphorus limited, and the phosphorus present is a determining factor for eutrophication and algal blooms.
NACWA works closely with USGS on a variety of issues related to water quality. Members with questions can contact Emily Remmel, NACWA’s Director of Regulatory Affairs & Outreach.