"Green"
This 13-letter word is the scientific term for a lake becoming overly enriched with nutrients.
What is Eutrophication.
These two elements, found in fertilizers, are the primary drivers of lake overnutrition.
What are nitrogen and phosphorus.
This "bloom" of microscopic plants is usually the first visible sign of a lake in trouble.
What is an algae bloom.
Falls Lake was created by this government organization in 1981 to prevent flooding.
What is the US Army Corps of Engineers.
This is the term for a "healthy" lake with low nutrient levels and clear water (the opposite of eutrophic).
What is Oligotrophic.
This specific type of "runoff" carries fertilizers from suburban lawns and golf courses into the lake.
When algae die, they sink and decompose, a process that consumes this gas needed by fish.
What is dissolved oxygen.
Falls Lake provides the primary source of this essential resource for the City of Raleigh.
What is drinking water.
This term refers to a body of water with extremely high nutrients, often resulting in "pea soup" water.
What is Hypertrophic.
These facilities remove contaminants before releasing treated water back into rivers.
What are wastewater treatment plants.
This "hypoxic" state occurs when water has so little oxygen that fish can no longer survive.
What is hypoxia.
This pigment, found in all green plants, is measured by the state to determine if Falls Lake is "impaired."
What is chlorophyll-a.
This process occurs in the summer when warm surface water sits on top of cold, oxygen-poor deep water.
What is Thermal Stratification.
This type of pollution comes from a single, identifiable source like a pipe rather than a wide area.
What is point source pollution.
Some "blooms" aren't just messy; they are toxic. This "blue-green" bacteria is a common culprit.
What is Cyanobacteria.
The "Falls Lake Rules" (put in place in 2011) aim to reduce this specific nutrient by 77% to restore the water.
What is phosporus.
This is the name for the area of land that drains all its water, and its nutrients, into a specific lake.
What is a Watershed (or Drainage Basin).
This specific form of Nitrogen (NO3) is highly soluble and easily leaches through soil into groundwater.
In the "Dead Zone" at the bottom of a lake, these organisms are the ones actually using up all the oxygen.
What are decomposers.
Much of the nutrient loading in Falls Lake comes from the "Upper Neuse" area, including this neighboring city.
What is Durham.