Description: The 2023 distribution of submerged aquatic vegetation (SAV) in Chesapeake Bay and its tributaries was mapped from aerial multispectral digital imagery and satellite imagery. The aerial imagery was acquired between May and October 2023, with a resolution of 24 cm, encompassing 194 flight lines.Due to challenges in acquiring access to the airspace surrounding Washington, DC, imagery for the upper Potomac River was not acquired until September 16th and October 24th, 2023. Unfortunately, SAV in this area began dying off starting in late August and so our imagery did not capture peak biomass of SAV. Neither WorldView or Pleiades satellite imagery was available for the areas in question. NAIP imagery was flown for both Virginia and Maryland in 2023, but it was not captured until October 11th, and so provided no additional information. Satellite imagery from Planet Labs was available, but does not provide high enough resolution for mapping without being used in conjunction with other imagery.
Copyright Text: SAV Monitoring Program, Virginia Institute of Marine Science
Description: The 2024 distribution of submerged aquatic vegetation (SAV) in Chesapeake Bay and its tributaries was mapped from aerial multispectral digital imagery and satellite imagery. The aerial imagery was acquired between May and October 2024, with a resolution of 24 cm, encompassing 189 flight lines. Due to a number of challenges, additional imagery was acquired from Maxar, SpaceWill, and Planet Labs in order to provide a more complete dataset for Chesapeake Bay. These imagery sources and their locations are detailed below:Aerial imagery was not acquired for portions of the Honga and Nanticoke Rivers and Fishing Bay. WorldView 2 satellite imagery acquired from Maxar through the NGA NextView program and PlanetScope satellite imagery from Planet Labs were used to map these areas.Due to late imagery acquisition, SuperView Neo 1 imagery from SpaceWill and PlanetScope satellite imagery from Planet Labs were used to supplement the aerial imagery for the upper Potomac River, including Nanjemoy Creek. PlanetScope imagery was also used to supplement the aerial imagery for the Pamunkey and upper Rappahannock Rivers and WorldView 2 satellite imagery acquired from Maxar through the NGA NextView program was used to supplement the aerial imagery for the Big Annemessex, Manokin, and Little Choptank Rivers, and Pocomoke and Tangier Sounds, as well as the Chesapeake Bay Eastern Shore from Hungars Creek to Onancock Creek.Due to turbid conditions, WorldView 2 satellite imagery acquired from Maxar through the NGA NextView program was used to supplement the aerial imagery for the Corrotoman, Piankatank, and lower Rappahannock Rivers, and Mobjack Bay.WorldView 2 satellite imagery acquired from Maxar through the NGA NextView program was used to supplement the aerial imagery for the Back, Bush, Gunpowder, Middle, Patapsco, and Sassafras Rivers, and the Susquehanna FlatsFifteen years of SAV data where SAV density was greater than 0 were combined and then dissolved to form SAV Habitat polygons. These polygons represent where SAV was located at least once during a period from 2010 to 2024.
Copyright Text: SAV Monitoring Program, Virginia Institute of Marine Science
Description: The 2010 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2012 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2013 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2014 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography and digital multispectral imagery with a 25cm GSD to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2015 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography and digital multispectral imagery with a 25cm GSD to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2015 Chesapeake Bay SAV Coverage was mapped from digital multispectral imagery with a 25cm GSD to assess water quality in the Bay. Each area of SAV was interpreted from the rectified imagry and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2018 Chesapeake Bay SAV Coverage was mapped from digital multispectral imagery with a 25cm GSD to assess water quality in the Bay. Each area of SAV was interpreted from the rectified imagry and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.
Copyright Text: SAV Ecology, Monitoring, & Restoration Program, Virginia Institute of Marine Science
Description: The 2010 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been distinguishable on the aerial photography.