Do Conservation Practices Help Local Streams? A USGS Chesapeake Study

Across the Chesapeake Bay watershed, the Chesapeake Bay Partnership is putting conservation practices (CPs) in place — such as stream fencing and forest buffers — to reduce the nutrients and sediment reaching the Bay. A U.S. Geological Survey study asks a related question: do those practices also make local streams healthier?

A USGS scientist measures stream habitat. Photograph by Leah Staub, U.S. Geological Survey.

The questions

• Key issue: How much do CPs benefit the health of local, non-tidal streams — "cobenefits" beyond the Bay?
• Unknowns: How do CPs change water quality and the stressors that affect stream life? Which practices help most?

The study aims to give managers:

• the effects of CPs on local water quality;
• how far the same practices also benefit stream ecosystems;
• a deeper understanding of local streams — their stressors and how CPs affect them — to choose efforts that help both water quality and stream health.

How conservation practices and other management change the way land uses create stressors that affect stream health. USGS.

The design

Management in the watershed targets landscapes with high nutrient and sediment loads and other damage. The USGS is doing year-long assessments in four:

In each, 30 streams were chosen to span a range of land use and how intensively CPs are used upstream, since responses are expected to depend on the local kind of farming or development and on each stream's drainage area.

Fencing and streamside forest-buffer plantings are essential tools with many benefits for streams. Photograph by David Fisher, U.S. Geological Survey.

Sampling locations (left) and expected stream health across gradients of conservation practices and land use (right): the healthiest streams are expected at top left, the most degraded at bottom right, and streams helped by conservation practices in the top half. USGS.

A whole-ecosystem approach

The team measures three things:

1. Upstream drivers — characteristics of the drainage area, including land use;
2. In-stream stressors — such as flow, temperature, erosion, nutrients, salinity, contaminants and invasive species;
3. Biological responses — in the water and along the banks.

That shows not only whether CPs and land use affect stream health but why, by identifying which stressors respond. The study can test whether streams with lots of CPs and light land use are healthiest, whether those with few CPs and intensive land use are least healthy, and whether, overall, more CPs mean healthier streams.

How the study assesses stream health, stressors and landscapes. USGS.

Scientists also assess the streamside land to see how it affects stream health. Photograph by David Fisher, U.S. Geological Survey.

Sharing the results

Yearly data from each landscape can show how much CPs affect local streams, which stressors do harm, and which landscape features go with better or worse streams. The USGS plans to share results by:

• a website mapping each stream's measurements against others in its landscape;
• discussions with local, state and federal agencies, nonprofits and landowners about how CP adoption connects to stream health;
• publishing findings so conservation managers elsewhere in the country can use them.

The USGS works with stakeholders to understand their needs and share how findings can inform management. Photograph by John Clune, USGS.

The study depends on private, nonprofit and public landowners who allowed access to their streams, and on the local managers who connected scientists with them. It is supported by USGS Chesapeake Bay Activities, a partnership of USGS and Virginia Tech scientists; the principal investigators are led by Greg Noe.

Sources

Based on U.S. Geological Survey Fact Sheet 2024–3030, "Connecting conservation practices to local stream health in the Chesapeake Bay watershed"; a work of the United States government in the public domain.