Without water quality data, pollution sources and impacts can not be identified. (riverkeeper.org)
A new analysis of 60 years worth of water quality data, however, suggests that efforts to control the nutrients are leading to smaller and shorter - lived dead zones. (conservationmagazine.org)
USGS operates more than 3,000 real - time stream gages and collects water quality data at numerous long - term stations throughout the Mississippi River basin and the Chesapeake Bay to track how nutrient loads are changing over time. (noaanews.noaa.gov)