State of Our Streams
This page was written for Durham residents to learn about stormwater issues and to provide updates on the condition of Durham's creeks. Technical reports, such as those required under the City's NPDES permit are also available.
The State of Our Streams is an annual communication campaign to City residents about the health and cleanliness of the City's creeks and rivers. This year's State of Our Streams report is based on conditions at 23 sites across the City. The Stormwater Quality group from Public Works takes samples monthly to assess conditions throughout the year.
Water Quality Index
Durham Stormwater uses an index specific to our City in order to express overall water quality at a specific location using a grading system. In watersheds where staff is able to take a wide variety of tests, the watershed is also given a grade through this Water Quality Index.
When we consider the health of a stream we look at four things:
- Bacteria: too much fecal bacteria in a stream can indicate sanitary sewer spills, private sewer spills, leaking/failing septic systems, or possibly an abundance of abandoned dog waste.
- Turbidity: too many small particles floating in the water of a stream from dirt and erosion affect the plants in the stream.
- Nutrients: nutrient overload (too much Nitrogen and Phosphorous) causes algal blooms and can happen when leaves, yard waste, and fertilizer enter our streams through storm drains.
- Aquatic Life: the kinds of animals that live in a stream demonstrate how healthy the stream is overall. By looking at the aquatic life in a body of water, we get a sense of its overall health.