The Audubon Naturalist Society Water Quality Monitoring Program is one of the largest and longest-running community science programs in the country. Since the early 1990s, the program has operated throughout Montgomery County, Maryland, and in parts of the District of Columbia. We provide our data to government agencies and to others upon request. Learn more about the history of water quality monitoring at ANS.

How It Works

Teams of volunteer monitors visit stream sites in April, July, October, and optionally during the winter. They conduct habitat assessments and collect and identify “benthic macroinvertebrates,” small organisms that live in the streams. Because these organisms exhibit a range of sensitivities to pollutants and stressors, they help us determine the streams’ health. Our program is distinct in that our monitors identify aquatic insects to the taxonomic level of family. This gives us a clearer picture of aquatic diversity and stream health than more general identification practices. Our program is also unique in that monitors learn to identify the organisms in the field and then release them alive, rather than preserving them in alcohol and sending them to a lab for identification.

Each team has a designated leader who is certified in identification. New volunteers are teamed with experienced monitors at stream sites convenient to them. Our water quality classes give volunteers the information they need to monitor. See what it's like--check out the video below!

Get Involved

Become a Volunteer Water Quality Monitor

Before going into the field, new monitors should have a basic knowledge of macroinvertebrate identification and stream ecology, either from previous training or by attending ANS’s water quality classes. Volunteers should also be willing to commit to at least two seasons of monitoring.

Ready to join a monitoring team? Apply Today! 

Reports & Data

Where We Monitor: see a map of all our community science data. Uncheck the box marked "Critter Survey" at the top left to see only Water Quality Monitoring sites.

Learn More

  • Check out the Conservation Blog for more news and reports from our community scientists!
  • For questions about monitoring with ANS, email Cathy Wiss. For information about water quality monitoring in Northern Virginia, email Dan Schwartz with the Northern Virginia Soil and Water Conservation District.
  • For information about the Chesapeake Monitoring Cooperative and bringing together volunteer data for government decision-making, click here.


Stream Science at ANS

For 25 years, ANS has been teaching the natural history of aquatic ecology and training volunteer stream monitors who track the health of our region’s streams. Learn from the experts: study stream science in our introductory classes, and you just might be inspired to become a stream monitor yourself! Our advanced classes are perfect for those interested in deepening their knowledge about biological stream monitoring and are taught by our Maryland Biological Stream Survey-certified instructor Cathy Wiss.

Registration & Fee Information
Registration required: click here to register online. The classes are open to anyone 10 years and older. Except for Macro ID Review & Quiz, prices for all classes are $15 Members/$25 non-members (plus a $1 registration fee per class); waivers are available for existing monitors and students earning SSL credit—email for details.

Introduction to Stream Science Series*
Classroom Session
Healthy Stream Biology
Section B: Wednesday, March 25 (7-9:30 pm) CANCELED
Section C: Tuesday, June 2 (7-9:30 pm)
(Sections A & B cover the same material)

Woodend Sanctuary, Chevy Chase, MD
In the classroom, we will explore how “benthic macroinvertebrates” – organisms that live in the bottom of streams – help us assess a stream’s health. We will learn how to identify these organisms to the taxonomic level of order through a PowerPoint presentation and by examining preserved specimens through a hands-on session with microscopes. REGISTER ONLINE

Field Workshop
Ten Mile Creek, Boyds, MD
Section A: Saturday, March 28 (9:30 am-12 pm) CANCELED
Section B: Saturday, June 6 (9:30 am-12 pm)

In the field workshop, we will visit a healthy stream to practice monitoring techniques and to collect and identify the benthic macroinvertebrates we find. REGISTER ONLINE

How to Read Your Stream* CANCELED
Thursday, March 19 (7-9:30 pm)
Woodend Sanctuary, Chevy Chase, MD

Learn about the influence of land uses on streams, stream character and dynamics, bank erosion, bar formation, substrate composition, different velocity-depth regimes, and the importance of riffles and riparian vegetation. We will practice assessing stream habitat by using photographs of streams and the forms that monitors fill out in the field. This class is recommended for anyone who plans to participate in the ANS water quality monitoring program and is a good refresher on habitat assessment for experienced monitors. REGISTER ONLINE

Advanced Series: Aquatic Insect Family ID**
Woodend Sanctuary, Chevy Chase, MD (7-9:30 pm)
A: Beetles, Megaloptera & Water Bugs, Thursday, January 30
B: Caddisflies & Aquatic Moths, Thursday, February 6
C: Dragonflies, Damselflies & True Flies, Thursday, February 13
D: Mayflies, Thursday, February 20
E: Stoneflies & Review, Thursday, February 27
Learn how to identify aquatic insects to the taxonomic level of family through this series of five classes. Identification to family level greatly enhances our understanding of stream ecology and the power of our monitoring data. These classes are great for fly fishermen, citizen science program or team leaders, aquatic resource biologists, and anyone interested in monitoring and understanding stream health. REGISTER ONLINE

Aquatic Insect ID Review & Quiz **
Section A: Saturday, March 7 (9:30 am-12 pm)
Section B: Tuesday, March 10 (6:30-9 pm)
Section C: Thursday, March 12 (6:30-9 pm)

Woodend Sanctuary, Chevy Chase, MD (No fee)
Time to separate the mayflies from the stoneflies! Those who wish to be certified to identify macroinvertebrates in the field in ANS’ program must demonstrate their ability annually by taking a quiz using preserved specimens. Those who do not take the quiz may still be assigned to a monitoring team to assist with data collection and other field logistics, but only those who have taken and passed the quiz will identify macroinvertebrates for data recording. REGISTER ONLINE

Know Your Invasive Plants
Saturday, May 30 (9:30 am-12 pm)

Woodend Sanctuary (Teale), Chevy Chase, MD
Invasive plants that kill or bring down mature trees can seriously alter stream health and ecosystem function. Volunteer Master Naturalist Diyan Rahaman will help you identify non-native invasive plants at Woodend and in nearby Rock Creek Park. An ANS/Rock Creek Conservancy Partnership.

*Recommended for anyone who plans to participate in the ANS Water Quality Monitoring Program

**Required for ANS Water Quality Monitoring Program team leaders

Resources for Volunteer Monitors

Are you an ANS or partner organization community-scientist who monitors regional streams? Here are some useful links to brush up on your protocols, download and print data forms, and more:

Macroinvertebrate Collection Forms

Habitat Forms

Program Scientific Resources

Are you interested in how we ensure the integrity of our data and calculate our stream health scores? Read up on the fundamentals behind our program: