Chesapeake Bay Activities Newsletter January-March 2022

Unique 20-year study assesses ecosystem response to different types of stormwater management

Issue: Managing stormwater runoff in developing areas

Assessing the habitat conditions to support freshwater fisheries in the Chesapeake Watershed

Issue: The Chesapeake Bay Program partners are striving to improve habitat conditions for recreational fisheries and other native fishes in the Bay and its watershed. While national fish habitat assessments have been conducted, resource managers need more local information to focus restoration and protection efforts in Chesapeake Bay watershed.

Conducting the fish-habitat assessments are challenging due to the size of the Bay and its watershed, which precludes direct surveys of all waters in an efficient and cost-effective manner. Predictive models can fill this gap by providing estimates of condition for these unsurveyed locations. Therefore, the USGS and NOAA are collaborating to improve fish-habitat assessments for inland waters and the estuary, using available data and innovative analytical methods with plans for a joint assessment in a pilot area.

Greatest Opportunities for Future Nitrogen Reductions to the Chesapeake Bay Watershed are in Developed and Agricultural Areas

Issue: As human population has increased, land-use changes have led to increases in nutrients (nitrogen and phosphorus) and sediment into the Bay. The excess nutrients cause algal blooms which contribute to water-quality impairments such as low oxygen or hypoxia (dead zones), and poor water clarity in the Chesapeake Bay. Management efforts to improve water quality focus on dissolved oxygen needed for fisheries, and water clarity needed for submerged aquatic grasses, which add oxygen into the Bay, provide habitat for fish, and food for waterfowl. Recreational and commercial fisheries in the Bay and its watershed are valued at more than $20 billion annually.

The statistical power to detect regional temporal trends in riverine contaminants in the Chesapeake Bay Watershed

Issue: Chemical contamination of riverine ecosystems is a global concern, with potentially negative effects for human and ecological health. Land management activities (e.g., Best Management Practices; BMPs) are an important tool that can be used to reduce point and non-point sources of pollution. The Chesapeake Bay Program (CBP) has goals for (1) reducing toxic contaminants and (2) reducing nutrients and sediment to improve water-quality conditions in the Bay and across the Chesapeake Bay Watershed. The BMPs to reduce nitrogen, phosphorus, and sediment also have a potential co-benefit of reducing toxic contaminants. However, the ability to confidently make predictions about the effects of land-management activities on reducing in-stream chemical concentrations is poorly understood. The CBP stakeholders need improved approaches to detect temporal changes (i.e., statistical power) in riverine chemical concentrations to help inform the design of monitoring programs; and to develop expectations regarding the amount of time needed to detect water-quality changes after BMP implementation (see figure 1).