{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -93.95851, 33.69514 ] }, "properties":{ "provider":"SWL", "code":"Millwood_Dam", "slug":"millwood_dam", "elevation":0.0, "horizontal_datum":"WGS84", "vertical_datum":"NGVD29", "state":"AR", "kind":"PROJECT", "nearest_city":"McNab", "public_name":"Millwood Dam", "location_code":564428150, "nsid":null, "aliases":{ "CWMS Legacy Naming":"Millwood_Dam", "NIDID":"AR00536", "CWMS Standard Naming":"Millwood_Dam" }, "timeseries":[ { "tsid":"Millwood_Dam-Headwater.%-Conservation Pool.Inst.1Hour.0.CCP-Comp", "label":"Percent Conservation Pool", "base_parameter":"%", "parameter":"%-Conservation Pool", "unit":"%", "unit_long_name":"Percent", "latest_time":"2026-04-14T22:00:00Z", "latest_value":100.0, "delta24h":null, "sort_order":14, "results":null }, { "tsid":"Millwood_Dam.Flow-Res In.Ave.1Hour.1Hour.6hr-RunAve-A2W", "label":"Inflow", "base_parameter":"Flow", "parameter":"Flow-Res In", "unit":"cfs", 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"units_long_name":"Feet" }, { "slug":"stor.bottom of normal", "label":"Bottom of Normal", "parameter":"Stor-Res", "base_parameter":"Stor", "tsid":"Millwood_Dam.Stor-Res.Inst.0.Bottom of Normal", "latest_value":40878, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of conservation", "label":"Top of Conservation", "parameter":"Stor-Res", "base_parameter":"Stor", "tsid":"Millwood_Dam.Stor-Res.Inst.0.Top of Conservation", "latest_value":188404, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor-Res", "base_parameter":"Stor", "tsid":"Millwood_Dam.Stor-Res.Inst.0.Top of Flood", "latest_value":1827623, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of inactive", "label":"Top of Inactive", "parameter":"Stor-Res", "base_parameter":"Stor", "tsid":"Millwood_Dam.Stor-Res.Inst.0.Top of Inactive", "latest_value":40878, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":549773, "associatedStructuresCount":1, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":88, "damLength":14500, "distance":null, "drainageArea":4144, "eapId":1, "dsacAssignedDate":"2024-10-10T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-05-02T12:00:00.000Z", "eapLastRevDate":"2023-07-17T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"AR00536", "oldFederalId":"AR00536", "hazardId":4, "hydraulicHeight":74, "inspectionAuthorityId":0, "inspectionDate":"2022-06-28T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":33.694479965, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-93.961167638, "maxDischarge":473300, "maxStorage":1854930, "nidHeight":88, "nidStorage":1854930, "normalStorage":172000, "numberOfLocks":0, "operationalStatusDate":"2009-05-12T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) operates and maintains more than 700 dams across the United States. A dam is an earthen embankment and/or solid concrete structure that is built across a river, stream, or other waterway to temporarily hold back and store water that would otherwise flow downstream. More detail related to this specific dam will be added at a future time.", "riskCharSummary":"USACE completed a risk assessment for Millwood Dam in June of 2022 that characterizes the risks associated with the project as low. The dam significantly reduces the risk of flooding to surrounding communities. However, it does not entirely eliminate the risk. Although Millwood Dam has historically performed well, extreme rainfall events may cause areas downstream to be flooded. Even when USACE operates the dam as intended, downstream flooding could still occur if a very large rainfall event were to require unusually large quantities of water to be released through the dam gates. In extreme cases, this flooding could be similar to what was experienced prior to the dam\u2019s construction. A less likely scenario would be if one of the gates were to have a problem during operation. In this case, more water than intended could be released, but that additional discharge would be limited to the amount that could pass through one gate. The most devastating potential scenario, but significantly less likely to happen, would occur if the dam were subjected to an extreme rainfall event that exceeded the damming surface. In this highly unlikely event, an uncontrolled release of water could flow out of the reservoir, resulting in potentially deadly flooding of Fulton, Arkansas and the Shreveport-Bossier City Metropolitan area, Coushatta, Louisiana and other downstream communities. Millwood Dam has an Emergency Action Plan to lower the risk of life loss if any of these scenarios occurred.", "riskManagementMeasures":"USACE performs ongoing inspection, maintenance, and monitoring activities to ensure the integrity of Millwood Dam and to reduce risk to downstream communities. The frequency of inspection and monitoring increases during high water events. USACE regularly updates the Emergency Action Plan for the dam and performs emergency response exercises with federal, state, and local emergency managers to remain prepared to respond to flood events affecting the dam. USACE also closely follows rainfall forecasts to determine when high water events may occur to provide information for any necessary flood warnings.", "riverName":"LITTLE", "separateStructuresCount":1, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":2, "spillwayWidth":0, "stateFedId":"AR00536", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":35, "submitDate":"2023-10-06T00:00:00.000Z", "surfaceArea":29000, "volume":8000000, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1966, "congDist":"Congressional District 04, Arkansas", "city":"FULTON", "county":"Little River", "aiannh":null, "websiteUrl":"https://www.swl.usace.army.mil/Missions/Recreation/Lakes/Millwood-Lake/", "coreTypeIds":"3", "damTypeIds":"11;8;9", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":"1;3", "nonFederalDamOnFederalId":0, "designerNames":"CESWT, CESWT", "otherNames":"Millwood Lake", "ownerNames":"USACE - Little Rock District", "ownerTypeIds":"3", "primaryDamTypeId":11, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;5;8", "dsacId":4, "femaRegion":"6", "lastEapExcerDate":"2024-02-13T12:00:00.000Z", "dataUpdated":"2025-01-31T12:00:00.000Z", "usaceDistrict":"Little Rock District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"111401", "doi_region":null, "doi_region_name":"Mississippi Basin", "doi_region_number":4, "thirtyYearAverage":284.8918, "tenthPercentile":262.1724, "ninetiethPercentile":323.1508 }, "id":564428150, "links":[ { "type":"application/json", "rel":"root", "title":"The landing page of this server as JSON", "href":"https://api.wwdh.internetofwater.app?f=json" }, { "type":"text/html", "rel":"root", "title":"The landing page of this server as HTML", "href":"https://api.wwdh.internetofwater.app?f=html" }, { "rel":"self", "type":"application/geo+json", "title":"This document as JSON", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/564428150?f=json" }, { "rel":"alternate", "type":"application/ld+json", "title":"This document as RDF (JSON-LD)", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/564428150?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/564428150?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }