{"id":344163,"date":"2026-01-07T15:00:00","date_gmt":"2026-01-07T05:00:00","guid":{"rendered":"https:\/\/science.nasa.gov\/earth\/earth-observatory\/algae-swirls-across-a-south-african-reservoir\/"},"modified":"2026-01-07T15:00:00","modified_gmt":"2026-01-07T05:00:00","slug":"algae-swirls-across-a-south-african-reservoir","status":"publish","type":"post","link":"https:\/\/www.vibewire.com.au\/?p=344163","title":{"rendered":"Algae Swirls Across a South African Reservoir"},"content":{"rendered":"<div id=\"\" class=\" hds-module hds-module-full alignfull wp-block-nasa-blocks-secondary-navigation\">\n<div class=\"hds-secondary-navigation-wrapper z-top width-100 padding-0\">\n<div id=\"\" class=\"hds-secondary-navigation width-full border-bottom-1px text-center hds-color-mode-dark hds-module hds-module-full alignfull wp-block-nasa-blocks-hdsnav\"><button type=\"button\" class=\"hds-secondary-nav-mobile-button display-flex tablet:display-flex desktop:display-none width-full flex-align-center 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class=\"usa-nav__submenu-item \"><a class=\"usa-nav__link\"  href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/subscribe\/feeds\/\" rel=\"noopener\">\ud83d\udedc RSS<\/a><\/li>\n<li class=\"usa-nav__submenu-item \"><a class=\"usa-nav__link\"  href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/contact-the-eo\/\" rel=\"noopener\">Contact Us<\/a><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/nav>\n<\/div>\n<div class=\"hds-secondary-navigation-menu-spacer\">\u00a0<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"\" class=\"width-full maxw-full margin-left-auto margin-right-auto hds-media-align-inline hds-module wp-block-nasa-blocks-video\">\n<div class=\"hds-cover-wrapper width-full maxw-full flex-column\">\n<div class=\"hds-video-container width-full embed-container\"><video title=\"Algae Blooms Swirl Across a South African Reservoir\" id=\"nasa-plus-NjWml\" class=\"video-js video-player vjs-fluid width-full\" data-setup='{\"controls\":true,\"preload\":\"auto\",\"plugins\":{\"mux\":{\"debug\":false,\"data\":{\"env_key\":\"91nns8oppqdfqc44lgo4b1gni\",\"player_name\":\"www.nasa.gov Player\",\"video_name\":\"Algae Blooms Swirl Across a South African Reservoir\"}}}}'  ><source src=\"https:\/\/assets.science.nasa.gov\/content\/dam\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeespoortdam_hls_20230712.mp4\" type=\"video\/mp4\"><p class=\"vjs-no-js\">To view this video please enable JavaScript, and consider upgrading to a web browser that<br \/>\n\t\t\t\t\t<a href=\"https:\/\/videojs.com\/html5-video-support\/\"  rel=\"noopener\">supports HTML5 video<\/a><\/p><\/video><\/div>\n<\/div>\n<div class=\"hds-media-caption hds-caption padding-y-2\">\n<div class=\"hds-caption-text p-sm margin-0\">\n<div>June 2022-July 2023<\/div>\n<\/div>\n<div class=\"hds-credits\">\n<div>NASA Earth Observatory \/ Lauren Dauphin<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p>On clear days in Hartbeespoort, South Africa, satellite images often reveal a reservoir with shades of deep blue interrupted by drifting patches of vivid green. These shifting features indicate algae blooms, which can affect water quality, ecosystems, and nearby human communities.<\/p>\n<p>In this animation, from June 2022 to July 2023, an algal bloom grows, moves around the reservoir, and then fades. The animation is composed of images from <a href=\"https:\/\/science.nasa.gov\/science-research\/earth-science\/harmonized-landsat-and-sentinel-2-collaboration-drives-innovation\/\" rel=\"noopener\">Harmonized Landsat and Sentinel-2<\/a> (HLS), a NASA product that combines imagery from the NASA\/USGS <a href=\"https:\/\/science.nasa.gov\/mission\/landsat-8\/\" rel=\"noopener\">Landsat 8<\/a> and <a href=\"https:\/\/science.nasa.gov\/mission\/landsat-9\/\" rel=\"noopener\">Landsat 9<\/a> satellites and the European Space Agency\u2019s Sentinel-2A, 2B, and 2C satellites.<\/p>\n<p>Algae is an umbrella term for photosynthetic organisms that live in water, encompassing everything from single-celled cyanobacteria to seaweed. They play a vital role in maintaining healthy ecosystems. But when colonies of algae spread too widely or release harmful toxins, they can threaten the very environments they support. These colonies are known as <a href=\"https:\/\/www.noaa.gov\/what-is-harmful-algal-bloom\" rel=\"noopener\">harmful algal blooms<\/a>, or HABs.<\/p>\n<p>Some HABs are toxic and often are part of a process called eutrophication. Eutrophication begins when there are too many nutrients in an ecosystem\u2014because of agricultural runoff and other inputs\u2014leading to a rapid growth of algae.<\/p>\n<p>\u201cIt\u2019s like having a garden,\u201d said Bridget Seegers, a NASA scientist who studies cyanobacteria in freshwater ecosystems. \u201cIf you add a lot of nutrients, you\u2019re going to have a lot of growth.\u201d<\/p>\n<p>Eventually, the algae die off. As decomposers break down the dead algae, they consume oxygen, which can lead to hypoxia and the formation of dead zones.<\/p>\n<div id=\"\" class=\"hds-media hds-module wp-block-image\">\n<div class=\"margin-left-auto margin-right-auto nasa-block-align-inline\">\n<div class=\"hds-media-wrapper margin-left-auto margin-right-auto\">\n<figure class=\"hds-media-inner hds-cover-wrapper hds-media-ratio-fit \"><a href=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810.jpg?w=720&#038;h=480&#038;%23038;fit=clip&#038;%23038;crop=faces%2Cfocalpoint\" rel=\"noopener\"><img fetchpriority=\"high\" decoding=\"async\" width=\"720\" height=\"480\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810.jpg?w=720&#038;h=480&#038;%23038;fit=clip&#038;%23038;crop=faces%2Cfocalpoint\" class=\"attachment-2048x2048 size-2048x2048\" alt=\"A satellite image of a mostly brown landscape features a dark-blue reservoir partially covered by bright green algae in the north and center.\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"eager\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810.jpg?w=720&#038;h=480&#038;fit=crop&#038;crop=faces%2Cfocalpoint 720w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810.jpg?w=300&#038;h=200&#038;fit=crop&#038;crop=faces%2Cfocalpoint 300w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810.jpg?w=400&#038;h=267&#038;fit=crop&#038;crop=faces%2Cfocalpoint 400w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810.jpg?w=600&#038;h=400&#038;fit=crop&#038;crop=faces%2Cfocalpoint 600w\" sizes=\"auto, (max-width: 720px) 100vw, 720px\" \/><\/a><\/figure><figcaption class=\"hds-caption padding-y-2\">\n<div class=\"hds-caption-text p-sm margin-0\">August 10, 2022<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\n<p>Such conditions have been documented at the Hartbeespoortdam (Hartbeespoort Dam) reservoir, located about 25 kilometers (16 miles) west of Pretoria and used primarily for recreation and irrigation. The reservoir is home to regular harmful algal blooms containing cyanobacteria. It also hosts large mats of invasive water hyacinths. While hyacinths do not produce toxins, they do contribute to eutrophication when they die and decompose.<\/p>\n<p>Harmful algal blooms can affect ecosystem health and human lives and livelihoods. In April 2023, South African authorities <a href=\"https:\/\/www.gov.za\/news\/media-statements\/water-and-sanitation-releases-investigation-report-cause-fish-kill\" rel=\"noopener\">linked a large fish kill<\/a> in Hartbeespoort to low oxygen levels caused by excessive algal growth. More broadly, HABs in drinking water reservoirs can reduce water availability and raise water treatment costs, while swimming in HAB-infested waters can cause rashes, and pets or livestock that drink it may fall ill or die.<\/p>\n<p>One <a href=\"https:\/\/doi.org\/10.3390\/rs14174277\" rel=\"noopener\">2022 paper<\/a> published in Remote Sensing examined algae in the reservoir from 1980 to 2020 using Landsat data. \u201cThis is a reservoir that has always been monitored heavily by the local department of water resources,\u201d said Adam Ali, the lead author of the paper. The research used satellite data to provide a big-picture view of conditions across the entire reservoir over long time scales. Using 40 years of Landsat data, the researchers found that the biggest drivers of algal growth were total phosphorus content\u2014a nutrient found in runoff\u2014and water temperature, with blooms typically expanding in the warm summer months and subsiding in the winter.<\/p>\n<p>They also identified key trends over space and time. Algal productivity was higher near Krokodilrivier (Crocodile River) inflows and in the western part of the reservoir due to golf course runoff and restricted water circulation, demonstrating how HABs are influenced by runoff and river inputs. Large blooms occurred between 1982 and 1986, when total phosphorus levels were high. A bioremediation program in the late 1980s succeeded in limiting algae growth, but after funding ended in the late 1990s, harmful algal blooms spiked again in the early 2000s.<\/p>\n<p>To track algae from space, the researchers analyzed the water\u2019s color by measuring different wavelengths of light. From this, they estimated the concentration of chlorophyll-a, a common pigment in algae, and used these values to approximate algae biomass over time. Although water samples remain necessary to confirm that a bloom is harmful, satellite data can help scientists understand the drivers of harmful algal blooms, especially in remote regions where regular ground monitoring is expensive and time intensive.<\/p>\n<p>New and forthcoming NASA missions promise to advance space-based water quality monitoring. The next Landsat satellite is expected to measure wavelengths specifically designed to detect HABs. NASA\u2019s <a href=\"https:\/\/science.nasa.gov\/mission\/pace\/\" rel=\"noopener\">PACE<\/a> (Plankton, Aerosol, Cloud, ocean Ecosystem) mission, launched in 2024, collects data in hundreds of precise wavelength bands in the visible spectrum, which can help scientists identify the type of algae that comprise a certain bloom\u2014a key factor in determining toxicity. Given PACE\u2019s spatial resolution, the data is most useful in coastal areas or larger inland water bodies. Ali is working with researchers at NASA Ames to integrate PACE into future studies.<\/p>\n<div style=\"height:30px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n<p><em>Animation by Ross Walter\/<em>Landsat Science Office Support<\/em><\/em>, <em>using data from the <a href=\"https:\/\/science.nasa.gov\/science-research\/earth-science\/harmonized-landsat-and-sentinel-2-collaboration-drives-innovation\/\" rel=\"noopener\">Harmonized Landsat and Sentinel-2<\/a> (HLS) product. Still image by Lauren Dauphin\/NASA Earth Observatory <em>using Landsat data from the\u00a0<\/em><a href=\"http:\/\/earthexplorer.usgs.gov\/\"  rel=\"noreferrer noopener\"><em>U.S. Geological Survey<\/em><\/a><\/em>. <em>Story by Madeleine Gregory\/Landsat Science Office Support.<\/em><\/p>\n<h2 class=\"wp-block-heading\"><strong>References &#038; Resources<\/strong><\/h2>\n<ul class=\"wp-block-list\">\n<li>Ali, K., <em>et al.<\/em> (2022) <a href=\"https:\/\/doi.org\/10.3390\/rs14174277\" rel=\"noopener\">Integrating In Situ and Current Generation Satellite Data for Temporal and Spatial Analysis of Harmful Algal Blooms in the Hartbeespoort Dam, Crocodile River Basin, South Africa<\/a>. <em>Remote Sensing<\/em>, 14(17), 4277.<\/li>\n<li>NOAA (2016, April 27) <a href=\"https:\/\/www.noaa.gov\/what-is-harmful-algal-bloom\" rel=\"noopener\">What is a harmful algal bloom?<\/a> Accessed January 6, 2026.<\/li>\n<li>South African Government (2023, April 26) <a href=\"https:\/\/www.gov.za\/news\/media-statements\/water-and-sanitation-releases-investigation-report-cause-fish-kill\" rel=\"noopener\">Water and Sanitation releases investigation report on cause of fish-kill at Hartbeespoort Dam<\/a>. Accessed January 6, 2026.<\/li>\n<\/ul>\n<div id=\"\" class=\"hds-featured-file-list bg-spacesuit-white padding-x-2 tablet:padding-x-3 desktop:padding-x-4 padding-y-5 desktop:padding-y-6 hds-module hds-module-full alignfull wp-block-nasa-blocks-file-list\">\n<div class=\"grid-container grid-container-block padding-0\">\n<div class=\"grid-row width-full margin-bottom-4\">\n<div class=\"grid-col-12 desktop:grid-col-6 margin-bottom-2 desktop:margin-bottom-0\">\n<h2 role=\"textbox\" class=\"heading-22\">\n\t\t\t\t\tDownloads\t\t\t\t<\/h2>\n<\/p>\n<\/div>\n<div class=\"grid-col-12 desktop:grid-col-6\">\n<div class=\"desktop:grid-col display-flex flex-align-center desktop:flex-justify-end\">\n\t\t\t\t\t\t\t\t\t<\/div>\n<\/p>\n<\/div>\n<\/div>\n<div class=\"hds-list-row hds-file-list-row\">\n<div class=\"hds-list-thumbnail hds-file-list-thumbnail\">\n<div class=\"hds-list-thumbnail-inner hds-file-list-thumbnail-inner hds-cover-wrapper\">\n<figure class=\"hds-media-background  \"><img decoding=\"async\" width=\"3425\" height=\"2531\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=3425&#038;h=2531&#038;%23038;fit=clip&#038;%23038;crop=faces%2Cfocalpoint\" class=\"attachment-thumbnail size-thumbnail\" alt=\"A satellite image of a mostly brown landscape features a dark-blue reservoir partially covered by bright green algae in the north and center.\" style=\"transform: scale(1.2); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"lazy\" data-video-loop=\"\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=3425&#038;h=2531&#038;fit=crop&#038;crop=faces%2Cfocalpoint 3425w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=300&#038;h=222&#038;fit=crop&#038;crop=faces%2Cfocalpoint 300w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=768&#038;h=568&#038;fit=crop&#038;crop=faces%2Cfocalpoint 768w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=1024&#038;h=757&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1024w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=1536&#038;h=1135&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1536w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=2048&#038;h=1513&#038;fit=crop&#038;crop=faces%2Cfocalpoint 2048w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=400&#038;h=296&#038;fit=crop&#038;crop=faces%2Cfocalpoint 400w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=600&#038;h=443&#038;fit=crop&#038;crop=faces%2Cfocalpoint 600w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=900&#038;h=665&#038;fit=crop&#038;crop=faces%2Cfocalpoint 900w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=1200&#038;h=887&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1200w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/algae-blooms-swirl-across-a-south-african-reservoir\/hartbeesdam_oli2_20220810_lrg.jpg?w=2000&#038;h=1478&#038;fit=crop&#038;crop=faces%2Cfocalpoint 2000w\" sizes=\"auto, (max-width: 3425px) 100vw, 3425px\" \/><\/figure>\n<\/div>\n<\/div>\n<div class=\"hds-list-details\">\n<div class=\"hds-list-name hds-file-list-name\">\n<h2 class=\"heading-22\">August 10, 2022 <\/h2>\n<\/p>\n<\/div>\n<div class=\"hds-list-meta\">\n<div class=\"hds-list-meta-item hds-list-date hds-file-list-date\">\n<p class=\"p-sm\">\n<\/div>\n<div class=\"hds-list-meta-item hds-file-list-filetype\">\n<p class=\"p-sm\">JPEG (3.33 MB)<\/p>\n<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div 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id=\"content-list-695de984ab54f\" class=\"hds-content-lists margin-y-3 padding-x-0 bg-spacesuit-white width-full maxw-full\" 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class=\"grid-container grid-container-widescreen padding-x-3\">\n<div class=\"grid-row flex-align-start margin-bottom-3\">\n<div class=\"desktop:grid-col-8 margin-bottom-2 desktop:margin-bottom-0\">\n<h2 class=\"section-heading-sm line-height-sm\">You may also be interested in:<\/h2>\n<p class=\"margin-top-0 margin-bottom-2 maxh-tablet\">Stay up-to-date with the latest content from NASA as we explore the universe and discover more about our home planet.<\/p>\n<\/p>\n<\/div>\n<\/div>\n<div class=\"grid-row grid-container grid-container-block padding-0 margin-0 flex-justify-center\">\n<div class=\" grid-col-12\">\n<div class=\"grid-row grid-container grid-container-block padding-0\" style=\"display: block\">\n<div id=\"filter-tags\" class=\"grid-col-12 filter-tags-container\"><\/div>\n<\/p>\n<\/div>\n<div class=\"smd-orbit-loader\" role=\"status\" aria-hidden=\"true\">\n<div class=\"orbit-plane\"><span class=\"orbit-dot\"><\/span><\/div>\n<\/div>\n<div id=\"post-list-container\" 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src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/iraq-reservoirs-plunge-to-low-levels\/iraq_farmland_oli_20250904_th.jpg?fit=clip&#038;crop=faces%2Cfocalpoint&#038;%23038;w=300\" ><\/figure>\n<p>            <\/a><\/p>\n<div class=\"hds-content-item-inner\">\n            <a href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/iraq-reservoirs-plunge-to-low-levels\/\" class=\"hds-content-item-heading\" rel=\"noopener\"><\/p>\n<div class=\"hds-a11y-heading-22\">Iraq Reservoirs Plunge to Low Levels<\/div>\n<p>            <\/a><\/p>\n<div class=\"hds-content-item-readtime label margin-bottom-1\">\n                    5 min read                <\/div>\n<p class=\"margin-top-0 margin-bottom-1\">A multi-year drought has put extra strain on farmers and water managers in the Middle Eastern country.<\/p>\n<div class=\"display-flex flex-align-center label color-carbon-60 margin-bottom-auto\"><svg version=\"1.1\" class=\"square-2 margin-right-1\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" x=\"0px\" y=\"0px\" width=\"16px\" height=\"16px\" viewBox=\"0 0 16 16\" style=\"enable-background:new 0 0 16 16;\" xml:space=\"preserve\"><g><g><path d=\"M8,0C3.5,0-0.1,3.7,0,8.2C0.1,12.5,3.6,16,8,16c4.4,0,8-3.6,8-8C16,3.5,12.4,0,8,0z M8,15.2 C4,15.2,0.8,12,0.8,8C0.8,4,4,0.8,8,0.8c3.9,0,7.2,3.2,7.2,7.1C15.2,11.9,12,15.2,8,15.2z\"\/><path d=\"M5.6,12c0.8-0.8,1.6-1.6,2.4-2.4c0.8,0.8,1.6,1.6,2.4,2.4c0-2.7,0-5.3,0-8C8.8,4,7.2,4,5.6,4 C5.6,6.7,5.6,9.3,5.6,12z\"\/><\/g><\/g><\/svg><span>Article<\/span><\/div>\n<\/p>\n<\/div>\n<\/div>\n<div class=\"hds-content-item content-list-item-post\">\n                    <a href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/lost-towns-of-the-quabbin-154605\/\" class=\"hds-content-item-thumbnail\" rel=\"noopener\"><\/p>\n<figure class=\"hds-media-background  content-list-thumbnail\"><img decoding=\"async\" loading=\"lazy\" data-no-id=\"true\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/imagerecords\/154000\/154605\/quabbin_oli2_20250603.jpg?fit=clip&#038;crop=faces%2Cfocalpoint&#038;w=300 300w\" alt=\"\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/imagerecords\/154000\/154605\/quabbin_oli2_20250603.jpg?fit=clip&#038;crop=faces%2Cfocalpoint&#038;%23038;w=300\" ><\/figure>\n<p>            <\/a><\/p>\n<div class=\"hds-content-item-inner\">\n            <a href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/lost-towns-of-the-quabbin-154605\/\" class=\"hds-content-item-heading\" rel=\"noopener\"><\/p>\n<div class=\"hds-a11y-heading-22\">Lost Towns of the Quabbin<\/div>\n<p>            <\/a><\/p>\n<div class=\"hds-content-item-readtime label margin-bottom-1\">\n                    4 min read                <\/div>\n<p class=\"margin-top-0 margin-bottom-1\">Forests play a key role in filtering the waters of a reservoir in central Massachusetts that\u2019s home to submerged towns\u2026<\/p>\n<div class=\"display-flex flex-align-center label color-carbon-60 margin-bottom-auto\"><svg version=\"1.1\" class=\"square-2 margin-right-1\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" x=\"0px\" y=\"0px\" width=\"16px\" height=\"16px\" viewBox=\"0 0 16 16\" style=\"enable-background:new 0 0 16 16;\" xml:space=\"preserve\"><g><g><path d=\"M8,0C3.5,0-0.1,3.7,0,8.2C0.1,12.5,3.6,16,8,16c4.4,0,8-3.6,8-8C16,3.5,12.4,0,8,0z M8,15.2 C4,15.2,0.8,12,0.8,8C0.8,4,4,0.8,8,0.8c3.9,0,7.2,3.2,7.2,7.1C15.2,11.9,12,15.2,8,15.2z\"\/><path d=\"M5.6,12c0.8-0.8,1.6-1.6,2.4-2.4c0.8,0.8,1.6,1.6,2.4,2.4c0-2.7,0-5.3,0-8C8.8,4,7.2,4,5.6,4 C5.6,6.7,5.6,9.3,5.6,12z\"\/><\/g><\/g><\/svg><span>Article<\/span><\/div>\n<\/p>\n<\/div>\n<\/div>\n<div class=\"hds-content-item content-list-item-post\">\n                    <a href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/reservoirs-dwindle-in-south-texas\/\" class=\"hds-content-item-thumbnail\" rel=\"noopener\"><\/p>\n<figure class=\"hds-media-background  content-list-thumbnail\"><img decoding=\"async\" loading=\"lazy\" data-no-id=\"true\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/20251118-reservoirs-dwindle-in-south-texas\/texas_lakecorpuschristi_oli2_20251011_th.jpg?fit=clip&#038;crop=faces%2Cfocalpoint&#038;w=300 300w\" alt=\"\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/2025\/20251118-reservoirs-dwindle-in-south-texas\/texas_lakecorpuschristi_oli2_20251011_th.jpg?fit=clip&#038;crop=faces%2Cfocalpoint&#038;%23038;w=300\" ><\/figure>\n<p>            <\/a><\/p>\n<div class=\"hds-content-item-inner\">\n            <a href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/reservoirs-dwindle-in-south-texas\/\" class=\"hds-content-item-heading\" rel=\"noopener\"><\/p>\n<div class=\"hds-a11y-heading-22\">Reservoirs Dwindle in South Texas<\/div>\n<p>            <\/a><\/p>\n<div class=\"hds-content-item-readtime label margin-bottom-1\">\n                    3 min read                <\/div>\n<p class=\"margin-top-0 margin-bottom-1\">Drought in the Nueces River basin is reducing reservoir levels, leaving residents and industry in the Corpus Christi area facing\u2026<\/p>\n<div class=\"display-flex flex-align-center label color-carbon-60 margin-bottom-auto\"><svg version=\"1.1\" class=\"square-2 margin-right-1\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" x=\"0px\" y=\"0px\" width=\"16px\" height=\"16px\" viewBox=\"0 0 16 16\" style=\"enable-background:new 0 0 16 16;\" xml:space=\"preserve\"><g><g><path d=\"M8,0C3.5,0-0.1,3.7,0,8.2C0.1,12.5,3.6,16,8,16c4.4,0,8-3.6,8-8C16,3.5,12.4,0,8,0z M8,15.2 C4,15.2,0.8,12,0.8,8C0.8,4,4,0.8,8,0.8c3.9,0,7.2,3.2,7.2,7.1C15.2,11.9,12,15.2,8,15.2z\"\/><path d=\"M5.6,12c0.8-0.8,1.6-1.6,2.4-2.4c0.8,0.8,1.6,1.6,2.4,2.4c0-2.7,0-5.3,0-8C8.8,4,7.2,4,5.6,4 C5.6,6.7,5.6,9.3,5.6,12z\"\/><\/g><\/g><\/svg><span>Article<\/span><\/div>\n<\/p>\n<\/div>\n<\/div>\n<\/div>\n<div id=\"pagination-container\" class=\"pagination\">\n<nav class=\"hds-pagination hds-pagination--content-lists\" role=\"navigation\" aria-label=\"Pagination Navigation\" data-mid-size=\"2\" data-end-size=\"1\" data-max-pages=\"4\" >\n<span aria-current=\"page\" class=\"page-numbers current\" 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decoding=\"async\" width=\"585\" height=\"425\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/about\/NASA-EO-Logo-mediumBlue2016-stacked-mark.png?w=585&#038;h=425&#038;%23038;fit=clip&#038;%23038;crop=faces%2Cfocalpoint\" class=\"attachment-1536x1536 size-1536x1536\" alt=\"\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"lazy\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/about\/NASA-EO-Logo-mediumBlue2016-stacked-mark.png?w=585&#038;h=425&#038;fit=crop&#038;crop=faces%2Cfocalpoint 585w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/about\/NASA-EO-Logo-mediumBlue2016-stacked-mark.png?w=300&#038;h=218&#038;fit=crop&#038;crop=faces%2Cfocalpoint 300w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/about\/NASA-EO-Logo-mediumBlue2016-stacked-mark.png?w=400&#038;h=291&#038;fit=crop&#038;crop=faces%2Cfocalpoint 400w\" sizes=\"auto, (max-width: 585px) 100vw, 585px\" \/><\/figure>\n<\/p>\n<\/div>\n<p>\t\t\t<\/a><br \/>\n\t\t\t\t\t<a href=\"https:\/\/science.nasa.gov\/earth\/earth-observatory\/image-of-the-day\/\" class=\"mobile:grid-col-12 tablet:grid-col-6 desktop:grid-col-3 topic-card margin-bottom-4 desktop:margin-bottom-0\" rel=\"noopener\"><\/p>\n<div class=\"hds-topic-card hds-cover-wrapper cover-hover-zoom bg-carbon-black\">\n<div class=\"skrim-overlay skrim-overlay-dark skrim-left mobile-skrim-top padding-3 display-flex flex-align-end flex-justify-start z-200\">\n<div>\n<h3 class=\"hds-topic-card-heading heading-29 color-spacesuit-white line-height-sm margin-top-0 margin-bottom-1\">\n\t\t\t\t\t\t\t\t<span>Earth Observatory Image of the Day<\/span><br \/>\n\t\t\t\t\t\t\t\t<svg viewBox=\"0 0 32 32\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><circle class=\"color-nasa-red\" cx=\"16\" cy=\"16\" r=\"16\"><\/circle><path d=\"M8 16.956h12.604l-3.844 4.106 1.252 1.338L24 16l-5.988-6.4-1.252 1.338 3.844 4.106H8v1.912z\" class=\"color-spacesuit-white\"><\/path><\/svg><br \/>\n\t\t\t\t\t\t\t<\/h3>\n<p class=\"margin-bottom-0 margin-top-2 color-carbon-20-important\">NASA&#8217;s Earth Observatory brings you the Earth, every day, with in-depth stories and stunning imagery.<\/p>\n<\/p>\n<\/div>\n<\/div>\n<figure class=\"hds-media-background  \"><img decoding=\"async\" width=\"2500\" height=\"1407\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=2500&#038;h=1407&#038;%23038;fit=clip&#038;%23038;crop=faces%2Cfocalpoint\" class=\"attachment-1536x1536 size-1536x1536\" alt=\"\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"lazy\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=2500&#038;h=1407&#038;fit=crop&#038;crop=faces%2Cfocalpoint 2500w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=300&#038;h=169&#038;fit=crop&#038;crop=faces%2Cfocalpoint 300w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=768&#038;h=432&#038;fit=crop&#038;crop=faces%2Cfocalpoint 768w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=1024&#038;h=576&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1024w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=1536&#038;h=864&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1536w, 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https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/esd\/eo\/images\/iotd\/iotd-banner.jpg?w=2000&#038;h=1126&#038;fit=crop&#038;crop=faces%2Cfocalpoint 2000w\" sizes=\"auto, (max-width: 2500px) 100vw, 2500px\" \/><\/figure>\n<\/p>\n<\/div>\n<p>\t\t\t<\/a><br \/>\n\t\t\t\t\t<a href=\"https:\/\/science.nasa.gov\/earth\/explore\/\" class=\"mobile:grid-col-12 tablet:grid-col-6 desktop:grid-col-3 topic-card margin-bottom-4 desktop:margin-bottom-0\" rel=\"noopener\"><\/p>\n<div class=\"hds-topic-card hds-cover-wrapper cover-hover-zoom bg-carbon-black\">\n<div class=\"skrim-overlay skrim-overlay-dark skrim-left mobile-skrim-top padding-3 display-flex flex-align-end flex-justify-start z-200\">\n<div>\n<p class=\"hds-topic-card-heading heading-29 color-spacesuit-white line-height-sm margin-top-0 margin-bottom-1\">\n\t\t\t\t\t\t\t\t<span>Explore Earth Science<\/span><br \/>\n\t\t\t\t\t\t\t\t<svg viewBox=\"0 0 32 32\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><circle class=\"color-nasa-red\" cx=\"16\" cy=\"16\" r=\"16\"><\/circle><path d=\"M8 16.956h12.604l-3.844 4.106 1.252 1.338L24 16l-5.988-6.4-1.252 1.338 3.844 4.106H8v1.912z\" class=\"color-spacesuit-white\"><\/path><\/svg>\n\t\t\t\t\t\t\t<\/p>\n<\/p>\n<\/div>\n<\/div>\n<figure class=\"hds-media-background  \"><img decoding=\"async\" width=\"1920\" height=\"1920\" src=\"https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=1920&#038;h=1920&#038;%23038;fit=clip&#038;%23038;crop=faces%2Cfocalpoint\" class=\"attachment-1536x1536 size-1536x1536\" alt=\"\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"lazy\" srcset=\"https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=1920&#038;h=1920&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1920w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=150&#038;h=150&#038;fit=crop&#038;crop=faces%2Cfocalpoint 150w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=300&#038;h=300&#038;fit=crop&#038;crop=faces%2Cfocalpoint 300w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=768&#038;h=768&#038;fit=crop&#038;crop=faces%2Cfocalpoint 768w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=1024&#038;h=1024&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1024w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=1536&#038;h=1536&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1536w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=50&#038;h=50&#038;fit=crop&#038;crop=faces%2Cfocalpoint 50w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=100&#038;h=100&#038;fit=crop&#038;crop=faces%2Cfocalpoint 100w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=200&#038;h=200&#038;fit=crop&#038;crop=faces%2Cfocalpoint 200w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=400&#038;h=400&#038;fit=crop&#038;crop=faces%2Cfocalpoint 400w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=600&#038;h=600&#038;fit=crop&#038;crop=faces%2Cfocalpoint 600w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=900&#038;h=900&#038;fit=crop&#038;crop=faces%2Cfocalpoint 900w, https:\/\/images-assets.nasa.gov\/image\/NHQ202212160009\/NHQ202212160009~large.jpg?w=1200&#038;h=1200&#038;fit=crop&#038;crop=faces%2Cfocalpoint 1200w\" sizes=\"auto, (max-width: 1920px) 100vw, 1920px\" \/><\/figure>\n<\/p>\n<\/div>\n<p>\t\t\t<\/a><br \/>\n\t\t\t\t\t<a href=\"https:\/\/science.nasa.gov\/earth\/data\/\" class=\"mobile:grid-col-12 tablet:grid-col-6 desktop:grid-col-3 topic-card margin-bottom-4 desktop:margin-bottom-0\" rel=\"noopener\"><\/p>\n<div class=\"hds-topic-card hds-cover-wrapper cover-hover-zoom bg-carbon-black\">\n<div class=\"skrim-overlay skrim-overlay-dark skrim-left mobile-skrim-top padding-3 display-flex flex-align-end flex-justify-start z-200\">\n<div>\n<p class=\"hds-topic-card-heading heading-29 color-spacesuit-white line-height-sm margin-top-0 margin-bottom-1\">\n\t\t\t\t\t\t\t\t<span>Earth Science Data<\/span><br \/>\n\t\t\t\t\t\t\t\t<svg viewBox=\"0 0 32 32\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><circle class=\"color-nasa-red\" cx=\"16\" cy=\"16\" r=\"16\"><\/circle><path d=\"M8 16.956h12.604l-3.844 4.106 1.252 1.338L24 16l-5.988-6.4-1.252 1.338 3.844 4.106H8v1.912z\" class=\"color-spacesuit-white\"><\/path><\/svg>\n\t\t\t\t\t\t\t<\/p>\n<\/p>\n<\/div>\n<\/div>\n<figure class=\"hds-media-background  \"><img decoding=\"async\" width=\"1536\" height=\"768\" src=\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?w=1536\" class=\"attachment-1536x1536 size-1536x1536\" alt=\"\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"lazy\" srcset=\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png 3600w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=300,150 300w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=768,384 768w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=1024,512 1024w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=1536,768 1536w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=2048,1024 2048w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=400,200 400w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=600,300 600w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=900,450 900w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=1200,600 1200w, https:\/\/science.nasa.gov\/wp-content\/uploads\/2023\/10\/biosphere-sea-2008-lrg.png?resize=2000,1000 2000w\" sizes=\"auto, (max-width: 1536px) 100vw, 1536px\" \/><\/figure>\n<\/p>\n<\/div>\n<p>\t\t\t<\/a>\n\t\t\t\t<\/div>\n<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Vivid green blooms form, drift, and fade in Hartbeespoortdam reservoir over the course of a year.<\/p>\n","protected":false},"author":13,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[16994,19017,19167,19168],"tags":[],"class_list":["post-344163","post","type-post","status-publish","format-standard","hentry","category-earth-observatory","category-surface-water","category-water-blooms","category-water-quality"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=\/wp\/v2\/posts\/344163","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=344163"}],"version-history":[{"count":5,"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=\/wp\/v2\/posts\/344163\/revisions"}],"predecessor-version":[{"id":345083,"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=\/wp\/v2\/posts\/344163\/revisions\/345083"}],"wp:attachment":[{"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=344163"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=344163"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vibewire.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=344163"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}