ICPRB recently updated an interactive map, Susceptibility to Runoff Impacts in the Potomac Basin, to help developers, zoning agencies, and other land use decision-makers identify areas most vulnerable to the impacts of stormwater runoff.

Impervious surfaces (parking lots, roads, sidewalks, etc.) prevent rain from slowly seeping into the ground. Instead, water runs swiftly off the land and directly into nearby streams. This increases the likelihood of flooding, damages the physical structure of the stream leading to erosion and excess sediment in the water, and carries trash and chemicals to our waterways.

Some areas are more vulnerable to these impacts than others based on landscape factors such as soil characteristics and slope. The interactive map includes a new color-coded “susceptibility index” of areas that may be most impacted by runoff. Those who make decisions on land use in the basin can use the information as a factor in siting new development, anticipating the effects of planned development and/or identifying areas where mitigation efforts may prove useful.

The map was published as part of the implementation of the Potomac Basin Comprehensive Water Resources Plan. The science behind the map is documented in a peer-reviewed paper written by ICPRB staff and published in the Journal of the American Water Resources Association.

ROCKVILLE, MD (February 3, 2026) – On January 31, the Izaak Walton League of America in partnership with the Interstate Commission on the Potomac River Basin (ICPRB) and the Montgomery County Department of Environmental Protection hosted a Winter Salt Awareness Week open house at the League’s national headquarters in Gaithersburg, Maryland.

Each year, 20 to 30 million tons of winter salt are applied across the United States to improve winter safety, but overuse comes at a significant cost to waterways, drinking water and infrastructure. Once applied, salt runs off paved surfaces and becomes a permanent pollutant—just one teaspoon can contaminate five gallons of water—posing long-term risks to freshwater ecosystems and public health. These impacts were highlighted during the Winter Salt Week open house, part of a nationwide campaign to raise awareness about winter salt pollution and promote reduction solutions.

The event was part of national Winter Salt Week which brought together local and regional partners who shared how their organizations are educating the public about smart salting practices and the effects of winter salt on wildlife, water quality and infrastructure. Additional regional events included webinars focused on winter smart salting for residents and property managers. The week was well timed this year, as there was an unprecedented snowfall event the weekend prior, leading to egregious oversalting and salt shortages across the country.

“The data shows that the Potomac River — the source of drinking water for millions in the DC metro area — is not only getting saltier, but the higher levels of salt can be found in the river even during the summer months”, said ICPRB Executive Director Michael Nardolilli. “So, salt is becoming persistent in the environment even when salt is no longer being applied on our roads and sidewalks in the winter. The time to reduce our winter salt use is now.”

The event featured a range of speakers representing local, state and regional organizations who discussed how data, policy and on-the-ground practices can reduce winter salt pollution. Maryland Delegate Linda Foley, District 15, Montgomery County spoke about the leadership of Delegate Lily Qi and the Izaak Walton League for working on legislation to reduce winter salt pollution across the state.

Priscilla To, Ph.D., water director at the Washington Suburban Sanitary Commission, said, “Safe, reliable drinking water starts at the source and source water protection is the first step.” WSSC Water and others are “collaborating together and getting things done.”

Montgomery County Councilmember-at-Large, Laurie-Anne Sayles noted that, “Environmental decisions are not just about the environment.” Those decisions are also about advancing equity because environmental decisions also affect the people who live, play, learn and work in the regions where those decisions have an impact—particularly those who have been historically marginalized and who will feel the effects of these decisions the most.

Leaders from the Izaak Walton League highlighted efforts to monitor chloride levels in waterways and use that data to drive changes in winter maintenance practices, while noting that we all still have work to do to reduce oversalting practices. “Most people are surprised to learn how little salt it actually takes to keep sidewalks and roads safe,” said Jared Mott, Interim Executive Director of the League. “Winter Salt Week is about giving people the knowledge they need to reduce pollution and protect local waterways. The League is proud to be a national leader in stopping winter salt pollution at the source, and we’re grateful to all our partners and especially want to thank everyone who participated today. Together, we can make our community a cleaner, healthier place to live and work while still protecting the safety of all that travel here in the winter months.”

Additional speakers from the ICPRB, Maryland Department of the Environment, Montgomery County Department of Environmental Protection and others discussed the work done to raise awareness around smart salting practices such as creating a state level road salt applicator training program. Participants also engaged in hands-on activities, including demonstrations by Jason Swope of the Chesapeake Conservation Landscaping Council of smart salting techniques for sidewalks and parking areas that showed how communities can stay safe, save money, and protect water resources while using less salt.

Attendees also brought water samples to be tested for salt pollution. League staff assisted attendees with water testing and helped them to report their results on the League’s online water quality database, the Clean Water Hub. Sixty-eight attendees came to the event, with one attendee describing the event as “energizing and magical.”

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Photos available upon request.

Click here for a PDF of News Release: Winter Salt Week Event Highlights Hidden Costs of Road Salt on Drinking Water and Rivers >>>

PRESS CONTACT:
Renee Bourassa, Director of Communications and Education
Interstate Commission on the Potomac River Basin | Rockville, MD
rbourassa@icprb.org | 301.417.4371 | www.potomacriver.org

The ICPRB is an interstate compact commission established by Congress in 1940. Its mission is to protect and enhance the waters and related resources of the Potomac River basin through science, regional cooperation, and education. Represented by appointed commissioners, the ICPRB includes the District of Columbia, Maryland, Pennsylvania, Virginia, West Virginia, and the federal government.

Winter drought; Be Winter Salt Smart; Millions of gallons of sewage spilled; and more, in this week’s Potomac News Reservoir – Jan. 22, 2026 >>>

River report: Snow in the forecast

This week’s U.S. Drought Monitor map shows 89 percent of the basin in Severe Drought conditions, holding steady from last week.

According to the experts, we could get a good amount of snow over the weekend. The snow-to-water equivalent depends on the type of snow, but on average 10 inches of snow equals 1 inch of rain. However, the slow snow melt will better help recharge groundwater and boost the river’s flow more than a quick storm.

The recharge is needed. At 1740 cubic feet per second (cfs), the flow at the USGS gage at Point of Rocks is only slightly above the historical low of 1500 cfs.

According to NOAA/NWS, rain in the watershed is 4 inches below average for the past 90 days.

Be Winter Salt Smart in 3-easy steps

With winter weather in the forecast this is a good time to think about your winter salting habits. Winter salt runs off into our rivers and streams to pollute our drinking water, damage infrastructure, and poison aquatic life. We can be safe while being winter salt smart and protecting our waterways.

Be winter salt smart in 3-easy steps:

1️⃣ Shovel first

2️⃣ Salt lightly (and only if needed)

3️⃣ Sweep it up after the storm

Just one teaspoon of salt permanently pollutes 5 gallons of drinking water.

Spread the word, not the salt! You can share these graphics on your social media pages to let your friends and family know about the impacts of too much winter salt. More graphics can be found on ICPRB’s Winter Salt Smart StoryMap.

ICPRB celebrates Winter Salt Week next week to bring awareness to this important issue. Join ICPRB at a regional event (virtual and in-person) to learn more about this issue. There are also national webinars on freshwater salinization, advocating for change, salt monitoring, and more.

Reminder: ICPRB hiring Director of Administration and Finance

The Director of Administration and Finance is a senior management position of ICPRB. A CPA certification is required. Applications are due by tomorrow, January 23. Learn more about the job and how to apply >>>

Our waterways are becoming saltier. Join ICPRB and our partners for a series of events in celebration of Winter Salt Week to raise awareness around salt pollution and reduction solutions.

There are also nationwide events for Winter Salt Week, which runs from January 26-30, 2026 with livestreams from experts across the country each day.

Webinar: Safe Sidewalks, Clean Water for Residents

Watch the recording on ICPRB’s YouTube page >>>
Read the presentation slide from the webinar >>>
January 21, 2026 | 1 – 1:30 pm
(Audience: general public)

Only 1 mug of salt is needed for 10 sidewalk squares.

This webinar explains how winter salt impacts our environment, why it’s a growing regional concern, and the simple steps you can take at home—before, during, and after storms—to apply just the right amount of salt to maintain safety in the winter. Learn application tips, alternatives to salt, and other ways you can be #wintersaltsmart while protecting the environment.

Speakers

• Renee Bourassa | Communications Director, Interstate Commission for the Potomac River Basin (ICPRB)
• Rebecca Murphy | Coastal Program Manager, Northern Virginia Regional Commission (NVRC)

Attendees will also have the chance to win a free sidewalk ice scraper! Winners will be selected at the end of each webinar.

Movie Night: Pollution in the Potomac

New Spire Arts: 15 West Patrick St, Frederick, MD
January 22, 2026 | 5 – 8 pm

What’s the current state of water quality in the Potomac River? What are PFAS chemicals and how do they impact our water? How does road salt fit into the pollution story, and what can we all do to make a difference? Learn about these topics and more, and catch a screening of the World’s Most Scenic River Journeys episode on the Potomac River, followed by presentations by the Potomac Riverkeepers and the City of Frederick Sustainability Department.

Webinar: Community Winter Salt Management

Watch the recording on NVRC’s YouTube page >>>
Read the presentation slide from the webinar >>>
January 23, 2026 | 1 – 1:30 pm
(Audience: HOAs, property managers, community associations, maintenance teams, etc.)
This session is tailored for HOA and other community association residents, board members, community managers, and maintenance team members. Gain best practices and resources for efficient winter salt use, contractor coordination, and strategies to reduce environmental damage while maintaining profitability and setting winter maintenance expectations. Hear from the Reston Association and Columbia Association on ways that they are taking action to improve winter salt management in their communities.

Speakers

• Benjamin Rhoades | Watershed Manager, Reston Association
• Janine Pollack | Watershed Manager, Columbia Association
• Camryn Arnstein | Natural Resources Planner, Maryland Department of the Environment (MDE)

Attendees will also have the chance to win a free sidewalk ice scraper! Winners will be selected at the end of each webinar.

DMV Winter Salt Week Open House

Registration is requested, but not required.
January 31st , 10am-1pm, Gaithersburg, MD
(Audience: general public, watershed organizations, and media)

Learn how salt affects our health and freshwater ecosystems, what’s being done, and how we can support local efforts to reduce road salt use. During the event we will hear from regional expert speakers, monitor the local waterways in Gaithersburg, Maryland for road salt pollution, and learn how much salt is needed to keep us safe during the winter while keeping environmental health in mind.