Why Raleigh Stormwater Samples Streams

News posted Sep. 08, 2017 - 6:00 am
Stream Sampling

Did you know that the City of Raleigh’s Stormwater Management Division collects stream samples to determine the water quality of local creeks and streams? In this Q&A, Raleigh Stormwater explains why stream sampling is so important.

What is done during a stream sampling?

LW: Stream sampling is done in two steps. First, City staff use field meters to gather information on a stream’s temperature, dissolved oxygen (DO), pH, and conductivity. Then, bottled samples are sent to a laboratory to test the amount of nitrogen, phosphorus, metals, and bacteria found in a stream.

Why is stream sampling done?

LW: We sample streams to meet requirements of our National Pollutant Discharge Elimination System (NPDES) permit managed by the N.C. Department of Environmental Quality (NCDEQ). Stream sampling also helps City staff identify high-priority areas where a stream may be heavily polluted.

Where are stream samples taken?

LW: We have 18 different sites that are monitored around the city. Two sites are in Crabtree Creek. The remaining 16 sites are located on smaller creeks that flow to Crabtree Creek and Walnut Creek, and ultimately to the Neuse River

How often are samples taken from streams?

LW: Samples are taken once every four months.

What do the stream samples tell us?

LW: Information from stream sampling is gathered over many years to track stream health and identify potential sources of pollution in creeks. Samples also help to determine whether efforts to improve water quality through our projects and programs are helping local waterways.

What are the benefits of stream sampling?

LW: Stream sampling provides an overview of a stream’s health. Continuing to monitor streams allows City staff to see long-term trends that determine the stream’s overall health.

How does the community benefit from stream sampling?

LW: We hope to use stream samples to identify areas that may benefit from stream restoration and water quality projects. Although the streams sampled are not used for Raleigh’s drinking water, taking samples give us an idea of the pollution that may be downstream.

How can residents get involved with stream sampling?

LW: We offer a Stream Monitoring Program that allows residents to monitor a stream in their neighborhood for a year or more. A workshop is held twice a year to teach residents how to use a stream monitoring kit and what to look for when monitoring a stream.

Why should residents get involved?

LW: When residents learn more about their neighborhood streams, they become more aware of the importance of maintaining good water quality, reporting water pollution, and making small changes to improve stream health, like using less fertilizer and picking up pet waste.

This article was originally printed in the Stormwater Management Division's Urban Watersheds publication. Subscribe to learn more and to receive stormwater-related news.

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