Indicator: Submerged Aquatic Vegetation (SAV) Abundance (1984-2024)

<p><strong>Access the Indicator Materials:</strong><br />- <a target="_blank" href="https://d18lev1ok5leia.cloudfront.net/chesapeakeprogress/Analysis-and_Methods-2024-Submerged-Aquatic-Vegetation-Final.pdf">Analysis &amp; Methods</a><br />- <a target="_blank" href="https://d18lev1ok5leia.cloudfront.net/chesapeakeprogress/Data-2024-Submerged-Aquatic-Vegetation-Final.xlsx">Data File</a><br />- <a target="_blank" href="https://gis.chesapeakebay.net/ags/rest/services/ChesapeakeProgress/cpSAV_beds_2010_2024/MapServer">Map Service</a></p><p>Acreage distribution and percent cover of submerged aquatic vegetation (SAV) in the Chesapeake Bay and its tributaries are measured from photo-interpreted aerial imagery collected during growing-season surveys. Satellite imagery is used when necessary to supplement aerial imagery and complete the dataset. The Chesapeake Bay Program Segmentation scheme divides the Bay into 93 segments grouped into four salinity zones: Tidal Fresh, Oligohaline, Mesohaline, and Polyhaline. The Bay is also divided into three geographic zones: the Upper Bay, which includes the Susquehanna River and extends to the Chesapeake Bay Bridge; the Middle Bay; and the Lower Bay, which extends to the mouth of Chesapeake Bay and includes the James River. SAV bed density is categorized into four classes based on a subjective comparison with the density scale, ranging from very sparse to dense.</p><p><strong>Note: This Indicator supported progress tracking toward the Submerged Aquatic Vegetation (SAV) Outcome in the original Chesapeake Bay Watershed Agreement, adopted in 2014. The Watershed Agreement and SAV Outcome were revised in 2025.</strong></p>