ShoreRivers is proud to announce that its Swimmable ShoreRivers bacteria monitoring program is now officially recognized with Tier III approval by the Chesapeake Monitoring Cooperative and the Maryland Department of the Environment, meaning the organization’s data can now be used to inform state regulatory decisions.
ShoreRivers is proud to announce that our Swimmable ShoreRivers bacteria monitoring program is now officially recognized with Tier III approval by the Chesapeake Monitoring Cooperative (CMC) and the Maryland Department of the Environment (MDE). This approval follows the successful completion of both accredited laboratory proficiency testing and a field audit. Because Tier III is the highest level of data quality recognized by MDE and CMC for community science water monitoring programs, our volunteer-collected bacteria data can now be used to inform state regulatory decisions, such as designating waterways as impaired and taking direct action against pollution sources.
This achievement is particularly critical because the Swimmable ShoreRivers program serves our community in a way that no other program, agency, or dataset does. In Maryland, bacteria monitoring and public reporting are only required if a state or local government designates an area as an official public swimming beach. However, a major gap exists on the Eastern Shore as very few areas carry this official designation. Results from those sites that do are rarely posted publicly or in a timely manner. Swimmable ShoreRivers directly fills this gap
This summer, nearly 70 SwimTesters are monitoring 55 sites across the Choptank, Miles, Wye, Chester, and Sassafras rivers; Eastern Bay; and the Bayside Creeks each week. These volunteers collect water samples which are then tested for Enterococci — a type of bacteria used to indicate fecal contamination in waterways. Special thanks go to our SwimTesters and our incredible site sponsors, who include local marinas, homeowners’ associations, families and municipalities, such as long-time supporters at the Town of Oxford, City of Cambridge, and Caroline County Recreation and Parks, and now Kent and Queen Anne’s counties, whose commissioners generously added our testing programs to their budgets this season.
Beyond weekly site monitoring, ShoreRivers also hosted its third annual Bacteria Blitz last month, engaging 49 community members across the Eastern Shore to collect water samples from their properties or favorite swimming spots. This community-wide effort empowers both ShoreRivers members and non-members to better understand local water quality while providing our Riverkeepers with valuable data from areas not routinely monitored through the Swimmable ShoreRivers program.
This year, 47% of the samples collected during the Bacteria Blitz passed Maryland’s recreational water quality standards. These results are a good reminder that water quality conditions can change quickly from place to place, depending on rainfall, runoff, tides, wildlife, and other environmental factors. Many of the sites tested during the Blitz had received rainfall prior to sample collection, which aids in the transport of bacteria to our rivers.
Whether testing is taking place or not, ShoreRivers recommends the following best practices when recreating in local waterways: rinse off after swimming, avoid swimming for 24–48 hours after a rain event, and stay out of the water with open cuts or wounds to minimize exposure to potentially harmful bacteria.
To explore our monitoring data on an interactive map, learn more about our work, or become a SwimTester volunteer or site sponsor for 2027, visit shorerivers.org/swim.