About Water Monitoring in Montgomery County

The water monitoring program is the cornerstone of the Department of Environmental Protection's (DEP) entire watershed program. Water quality monitoring includes:

• Instantaneous water chemistry and testing
• Assessments of the biological community living in our streams and waterways
• Assessments of the structure, flow, and condition of the stream itself

Stream monitoring supports water resource management in the County in many ways:

• Assessing and tracking the health of the County's subwatersheds over time
• Identifying pollutants in the County's water bodies
• Prioritizing watersheds for restoration by allowing DEP to assess and compare watersheds
• Tracking water quality outcomes of watershed restoration projects
• Identifying stream segments that are severely impaired and need remediation for long-term watershed health
• Assessing the effectiveness of controls to capture, slow down, and filter stormwater runoff (as mandated in the County's Stormwater Permit)
• Evaluating water quality responses and trends closely in Special Protection Areas (SPAs)
• Helping DEP to meet the County's water quality goals and legally mandated water quality standards
• Fulfilling the legal requirements in the County's stormwater permit to provide ongoing assessments of County waterways.

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Where is the pollution?

Streams are often at the receiving end of rainfall (stormwater) runoff from land surfaces and local stormwater drain-pipe systems. Stormwater pollution, as well as sewage from leaky sewer lines and contamination from landfills, can shock a stream system for a brief period. But if these influences are persistent and repeated, they can degrade streams and the aquatic habitat for insects, fish, stream salamanders, and other biological communities.

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Where is DEP monitoring?

All County watersheds are monitored in detail once every 5 years according to a defined schedule. The map below illustrates the 5-year rotational biological monitoring schedule. The streams in SPAs are monitored every year.

In 2010 DEP is monitoring the following watersheds for its Baseline Monitoring Program, in addition to all SPAs:

• Patuxent River
• Rock Run
• Little Monocacy
• Dry Seneca
• Horsepen Branch
• Sopers Branch of the Little Bennett Creek

Proposed baseline monitoring schedule for Montgomery County, MD.

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