{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Scott Paulinski", "hasEmail": "mailto:spaulinski@usgs.gov"}, "description": "The U.S. Geological Survey (USGS), in cooperation with the Water Replenishment District of \nSouthern California, developed a regional groundwater model of the Los Angeles Coastal Plain \n(LACP) incorporating new data, analyses, and modeling tools to better understand the \nhydrogeology of the groundwater basins.  The LACP covers about 580 square miles and is the \nlargest coastal plain of semiarid southern California. This aquifer is heavily developed with mostly \nresidential, commercial, and industrial use and relies heavily on groundwater for its water supply. \nThere has been a heavy reliance on groundwater from the LACP for many years. The need to \nreplenish the groundwater basins within the LACP was recognized as far back as the 1930s, \nwhen spreading grounds were first used to replenish groundwater basins and store water \nunderground during times of water surplus to meet demands in times of shortage. Seawater\n intrusion resulting from fresh-water pumping became significant in the 1940s. As a result, \ninjection of imported water through wells at what is now the West Coast Basin Barrier Project \nbegan on an experimental basis in 1951. Managed aquifer recharge from the spreading grounds \nand barrier wells is an important part of the LACP's groundwater supply. This study, in cooperation \nwith the Water Replenishment District of Southern California, involved an assessment of the \nhistorical and present status of groundwater resources in the LACP and the development of tools \nto better understand the groundwater system. The Los Angeles Coastal Plain Groundwater Model \n(LACPGM) developed for this study, represents a major update of a previous groundwater model \ndeveloped by Reichard and others (https://doi.org/10.3133/wri034065). The LACPGM uses the \nUSGS model code MODFLOW-USG, which enables the use of an unstructured finite-difference \ngrid which contains nodes one-eighth mile (mi; 660 ft) in length and width. The LACPGM \nincorporates 12 layers for the 13 chronostratigraphic units, with the two bottom units modeled \nas a single layer. MODFLOW-USG was selected for its ability to effectively represent the \ndiscontinuous and faulted chronostratigraphic layers using an unstructured grid. The LACPGM \nsimulates groundwater flow in the LACP using quarterly stress periods from 1971 to 2015. \nThe model was used to predict water levels under future water-management scenarios, base \ncase wet and dry scenarios, increased pumpage wet and dry scenarios, and optimized \nreplenishment wet and dry scenarios. The scenarios include projected future pumping rates \nand estimate the increases in water spreading and injection that would be needed to maintain \nwater levels. The scenarios simulate expected future pumping rates and estimate needed \nincreases in water spreading and injection in order to maintain water levels. This USGS data \nrelease contains all the input and output files for the simulations described in the associated \nmodel documentation report (https://doi.org/10.3133/sir20215088).\t\n\t\t\t", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/P9H15ZAX", "description": "Landing page for access to the data", "format": "XML", "mediaType": "application/http", "title": "Digital Data"}, {"@type": "dcat:Distribution", "description": "The metadata original format", "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.9980eb9a-33d8-4de0-9edd-4d1bffa6135d.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_9980eb9a-33d8-4de0-9edd-4d1bffa6135d", "keyword": ["Bell Gardens", "California", "Carson", "Cerritos", "Compton", "Downey", "Gardena", "Groundwater", "Groundwater Model", "Hawthorn", "Hollywood", "Inglewood", "InlandWaters", "Lakewood", "Long Beach", "Los Angeles", "Los Angeles County", "Lynwood", "MODFLOW-USG", "Montebello", "Norwalk", "PEST", "Pico Rivera", "Santa Monica", "Santa Monica Bay", "Santa Pedro Bay", "South Gate", "Torrance", "USGS:9980eb9a-33d8-4de0-9edd-4d1bffa6135d", "Whittier", "Wilmington", "environment", "geoscientificInformation", "inlandWaters", "usgsgroundwatermodel"], "modified": "2021-09-01T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-118.571863, 33.659798, -117.886523, 34.130930", "theme": ["geospatial"], "title": "MODFLOW-USG model used to evaluate water management issues in the Los Angeles Coastal Plain, California"}