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Stream Monitoring

Watershed Management and Monitoring
Phone: 410-887-5683
Fax: 410-887-3510

Water Quality Check Up

A healthy stream often indicates a healthy community.
Many factors are important to
maintaining a healthy stream.

While many people go to their doctor for a medical exam every year, Baltimore County waterways are getting screened even more often to make sure our environment is safe and healthy.

In Baltimore County, streams, rivers, lakes, inlets, shorelines and other surface waters receive a check up from the Department of Environmental Protection and Sustainability (EPS). EPS is charged with the task of assessing and maintaining the water quality in local streams. Just like a check list that the doctor may use during your annual physical, the waterways are evaluated for a particular set of physical, chemical and biological conditions.

Those three factors are evaluated using methods and frequency that help provide a picture of the waterway’s health and give EPS an opportunity to identify trends. This helps to answer questions about whether the waterway’s health is improving, remaining consistent, or deteriorating.

Physical Stream Habitat

The physical condition of the stream refers to the state of the banks and channels of waterways. The survey examines whether there is significant erosion, if the channel is changing, if sediment is accumulating in areas and whether there is an abundance of debris or trash. These issues are all related to the physical condition of the waterway. Thirty sites are part of a long-term study to monitor erosion and other changes in the physical state of the waterway. In addition, Baltimore County is working to catalog all 2,100 miles of stream by having teams walk the streams and create reports on the stream and the area immediately surrounding it.

Chemical Content

It is also important to know what is in the water. An analysis of the chemical content of the water provides a snapshot of the quality of the water. Over 100 sites are monitored for chemical conditions six to eight times during the year. Another two locations are monitored monthly. Just as your doctor doesn’t randomly check for every conceivable disease during your annual check up, EPS conducts chemical analysis for nutrients, heavy metals, total solids and bacteria. These items are likely pollutants. Also, just like your own physician, if there are indications of a problem, additional tests may be conducted.

Living Resource

Another way to measure water quality is to consider the creatures living in the stream. Even small streams are home to fish, insects and other aquatic life. Assessing biological conditions involves conducting an inventory of the species of fish and insects living in the waterway. Some species are more tolerant of pollutants than others. If a species is present that can only live in very clean water, then this indicates that the water is healthy. Likewise, if only the most pollutant tolerant species can be found, then the water quality is likely impacted. Every spring, insects are collected at over 100 locations around the county and analyzed by species. Fish species are analyzed every summer in cooperation with the Maryland Department of Natural Resources.

Revised June 18, 2015

Revised April 6, 2016         


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