Why Loudoun’s Streams Matter
Clean water isn’t just an environmental issue — it’s personal. The streams flowing through our woods, farms, neighborhoods, and parks are your drinking water source, wildlife habitat, and community assets – and impact our downstream neighbors from the Potomac to the Chesapeake Bay.
Our Monitoring Programs: Science in Action
Benthic Macroinvertebrate Monitoring
Stream Health from the Bottom Up
Since 1995, our volunteers have monitored benthic macroinvertebrates — the aquatic insects and small animals living on the stream bottom. These “macros” are nature’s water quality indicators and tell us the story of the health of our streams.
With 32 certified monitors and many additional volunteers, we will complete 50 biological surveys at 28 sites across the county in 2025. The Report Card’s biological monitoring score (C, 52%) tells us that pollution-tolerant species are becoming more common than sensitive ones—a clear warning sign that streams are under pressure.
Data is shared on the Clean Water Hub. See the map below for our Loudoun County area locations.
Watch benthic monitoring video| Learn more about our benthic monitoring
Salt Watch Program
Launched in 2020 in partnership with the Izaak Walton League of America, Loudoun Wildlife’s Salt Watch program has grown from 9 volunteers at 14 sites to over 100 volunteers monitoring nearly 80 sites across 23 streams. Our program now contributes 15% of all nationwide Salt Watch data—making Loudoun a leader in tracking road salt pollution.
Volunteers test chloride levels at local streams twice monthly year-round and during winter weather events, helping identify salt pollution hotspots and advocate for smarter salt use.
All data is publicly shared on the Clean Water Hub. See the map above for more info.
Learn more about Salt Watch →
Chemical Monitoring Program
Digging deeper into water quality.
Launched in 2023 in partnership with the Alliance for the Chesapeake Bay, our “Chem Crew” of 13 dedicated volunteers conducts monthly monitoring at six sites along Tuscarora Creek and Town Branch in Leesburg—two urban streams showing concerning water quality trends. These measurements identify pollution sources and provide insights that benthic surveys alone cannot reveal—painting a complete picture of stream health that guides targeted restoration efforts.
Data is available on the Chesapeake Monitoring Cooperative Data Explorer (search by Water Quality Data and Group – Loudoun Wildlife Conservancy)
Watch chemical monitoring video
Securing Clean Drinking Water for Lucketts
Our monitoring data doesn’t just document problems—it drives solutions. When volunteers discovered alarming E. coli levels in streams near Lucketts in 2021, their findings triggered action that protected an entire community’s drinking water.
In 2022, Loudoun Wildlife Conservancy received a $41,432 grant to secure clean drinking water for the Lucketts community from the Tides Foundation, on the recommendation of the Google Data Centers Grants Fund. Loudoun Wildlife implemented a one-year comprehensive water quality testing program and public outreach events to promote awareness of, and provide services for, clean drinking water to the community.
Learn more about the Lucketts project
Get Involved
Our volunteers don’t just monitor streams—they shape policy, inspire students, empower people to take action to improve stream health, and build a community that values clean water.
If you would like to learn more about how you can get involved, contact our Stream Monitoring Program Coordinator Amy Ulland at aulland@loudounwildlife.org.
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Recognition & Impact
In 2023, our Stream Monitoring volunteers received the first-ever Environmental Excellence Award from Loudoun County’s Environmental Commission—recognition of the dedication that makes this work possible.
