{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -93.19469, 34.57283 ] }, "properties":{ "provider":"MVK", "code":"Blakely", "slug":"blakely", "elevation":0.0, "horizontal_datum":"NAD27", "vertical_datum":"NGVD29", "state":"AR", "kind":"PROJECT", "nearest_city":"Hot Springs", "public_name":"Blakely Mountain Dam", "location_code":11092013, "nsid":null, "aliases":{ "CWMS Standard Naming":"Blakely", "SHEF Location ID":"CE418B32", "DCP Platform ID":"CE418B32", "NIDID":"AR00150", "CWMS Legacy Naming":"Blakely" }, "timeseries":[ { "tsid":"Blakely.%.Inst.1Hour.0.Percent Full", "label":"Percent Flood Pool", "base_parameter":"%", "parameter":"%", "unit":"%", "unit_long_name":"Percent", "latest_time":"2026-08-25T21:00:00Z", "latest_value":0.0, "delta24h":null, "sort_order":12, "results":null }, { "tsid":"Blakely.Elev.Inst.1Hour.0.DCP-rev", "label":"Elevation", "base_parameter":"Elev", "parameter":"Elev", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-08-25T21:00:00Z", "latest_value":572.83, "delta24h":null, "sort_order":1, "results":null }, { "tsid":"Blakely.Stor.Inst.1Hour.0.DCP-rev", "label":"Flood Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-08-25T21:00:00Z", "latest_value":1953123.9, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"Blakely.Precip.Inst.1Hour.0.DCP-rev", "label":"Precipitation", "base_parameter":"Precip", "parameter":"Precip", "unit":"in", "unit_long_name":"Inches", "latest_time":"2026-08-25T21:00:00Z", "latest_value":201.62, "delta24h":null, "sort_order":16, "results":null } ], "name":"Blakely Mountain Dam", "hasResopsAverages":"true", "nidId":"AR00150", "nidid":"", "levels":[ { "slug":"elev.streambed", "label":"Streambed", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Blakely.Elev.Inst.0.Streambed", "latest_value":385, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"elev.top of conservation", "label":"Top of Conservation", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Blakely.Elev.Inst.0.Top of Conservation", "latest_value":578, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"elev.top of dam", "label":"Top of Dam", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Blakely.Elev.Inst.0.Top of Dam", "latest_value":616, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"elev.top of flood", "label":"Top of Flood", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Blakely.Elev.Inst.0.Top of Flood", "latest_value":592, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"elev.top of power", "label":"Top of Power", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Blakely.Elev.Inst.0.Top of Power", "latest_value":578.1, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"elev.top of surcharge", "label":"Top of Surcharge", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Blakely.Elev.Inst.0.Top of Surcharge", "latest_value":610.2, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stor.top of conservation", "label":"Top of Conservation", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Blakely.Stor.Inst.0.Top of Conservation", "latest_value":2151100, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Blakely.Stor.Inst.0.Top of Flood", "latest_value":2768500, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" }, { "slug":"stor.top of power", "label":"Top of Power", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Blakely.Stor.Inst.0.Top of Power", "latest_value":2151100, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" }, { "slug":"stor.top of surcharge", "label":"Top of Surcharge", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Blakely.Stor.Inst.0.Top of Surcharge", "latest_value":3761500, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" } ], "id":549800, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":226, "damLength":1100, "distance":4, "drainageArea":1105, "eapId":1, "dsacAssignedDate":"2020-07-21T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-02-22T12:00:00.000Z", "eapLastRevDate":"2021-02-02T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"AR00150", "oldFederalId":"AR00150", "hazardId":4, "hydraulicHeight":216, "inspectionAuthorityId":0, "inspectionDate":"2024-04-25T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":34.573008407, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-93.195011878, "maxDischarge":45000, "maxStorage":3760700, "nidHeight":240, "nidStorage":3760700, "normalStorage":2151100, "numberOfLocks":0, "operationalStatusDate":"2020-07-21T12:00:00.000Z", "operationalStatusId":2, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"Nestled in the Ouachita Mountains of southwest Arkansas across the Ouachita River, Blakely Mountain Dam is located 10 miles west of Hot Springs. The United States Army Corps of Engineers (USACE) constructed the dam in 1955 with the primary purpose of reducing the frequency of flooding to downstream communities along the Ouachita River. The dam also produces hydropower on demand for Arkansas Southwest Power Administration (SWPA) and provides recreation opportunities along the reservoir and adjacent forested lands. Additionally, downstream areas rely on the dam to release enough continuous flows so that river water levels are sufficient for communities to draw drinking water and for support of wildlife.\n\nThe dam structure is an earthen embankment that stands over 200 feet high and is armored with a rock riprap cover. A separate overflow spillway structure is located in a ridge approximately one mile west of the dam at the end of the first upstream cove. The spillway, made up of compacted soil lined with rock (with a concrete saddle across the top), is designed to remove excess water from the reservoir after extremely heavy rainfall. However, to date, the spillway at Blakely Mountain Dam has not been used.\n\nIn 1980, routine maintenance of instrumentation resulted in a point of high pressure within the dam that potentially caused cracking along the contact between the embankment and the foundation. USACE closely monitors the area and installed an earthen berm in 2009 that collects water moving through the dam to see if there are any changes that would indicate a possible increase in water seeping through and eroding the dam. USACE has also taken measures to prevent similar high-pressure incidents from occurring in the future. Today, the areas downstream of the project that could be impacted from failure of the dam include over 44,000 residents, and the dam reduces the frequency of flooding to homes and business along with a variety of infrastructure including hospitals, schools, power generation facilities, water treatment facilities, and more. To prepare your family against possible flooding, please visit the National Inventory of Dams (NID) website to see maps showing the potential extent of flooding locations if Blakely Mountain Dam were to breach.", "riskCharSummary":"USACE completed a risk assessment for Blakely Mountain Dam in April 2020 and has classified the risks associated with the project as moderate. A major storm with significant rainfall west of Hot Springs, upstream of Lake Ouachita, would lead to significant increases in the reservoir level which could potentially cause the dam to overtop and fail.\n\nIf the reservoir level rises above the overflow spillway, water would spill across the concrete saddle at the top, potentially causing it to break apart as the water erodes the earthen and rock spillway below. Because the spillway has not been used in the past, there is uncertainty about how it would perform in such a situation. Another issue is the possibility of cracking where the earthen dam contacts the rock foundation below, leading to water seeping through and causing erosion along the crack. Water flowing through even a small fracture could continue to grow, allowing more water to flow through, eventually leading to a failure.\n\nAs a result of either of these scenarios, near downstream areas along the Ouachita River including Mountain Pine could have less than one hour to evacuate while areas farther downstream, from Hot Springs to Malvern, would also need to evacuate quickly. In a worst-case scenario, a large portion of land in Garland and Hot Spring Counties will experience some flooding, and local highways would be flooded. Flooding downstream would be swift and deep, destroying buildings and infrastructure, potentially killing anyone remaining in the area. It could cause water depths across highways 27, 70 and 270 so deep that those roadways would need to be closed. In addition, the downstream reservoirs of Lake Hamilton and Lake Catherine would also quickly fill with water and overflow.\n\nAdditionally, reservoir levels that rise above the overflow spillway at Blakely Mountain Dam will lead to increased downstream water levels in Lake Hamilton and Lake Catherine, even if failure of the dam or spillway does not occur. Because Lake Ouachita has never experienced reservoir levels to this degree, downstream communities may not be aware of the potential for high water downstream of Blakely Mountain Dam during spillway flow.", "riskManagementMeasures":"To ensure Blakely Mountain Dam continues to operate to minimize flood risk and provide hydroelectric and water supply benefits, USACE has developed a surveillance and monitoring plan for the project, and performs increased surveillance during flooding with continuous monitoring of the dam at greater frequencies during periods of high water. USACE regularly inspects the dam and its components quarterly, annually, and periodically at various levels of detail. USACE also keeps emergency supplies and equipment on-site to be able to quickly respond to and flood fight any incidents that could occur at the dam.\n\nUSACE performs periodic risk assessments on a 10-year frequency with the most recent assessment performed in 2020 to identify issues, determine project risk, and quantify downstream impacts. Interim Risk-Reduction Measures (IRRMs) are in place to reduce the risk of the project in the near term which includes a berm and a seepage collection system which have been installed at the dam to monitor for seepage. Other risk management actions include community outreach to increase risk awareness, periodic interactions with local Emergency Managers to increase state and local official preparedness, and emergency exercises on a 5-year frequency to practice the project's Emergency Action Plan (EAP).", "riverName":"OUACHITA RIVER", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":200, "stateFedId":"AR00150", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":240, "submitDate":"2023-02-16T17:25:38.431Z", "surfaceArea":40100, "volume":4215000, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1953, "congDist":"Congressional District 04, Arkansas", "city":"MOUNTAIN PINE", "county":"Garland", "aiannh":null, "websiteUrl":"https://www.usace.army.mil/Missions/Civil-Works/Dam-Safety-Program/Article/2870967/dam-safety-program/", "coreTypeIds":"3", "damTypeIds":"8", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":"1", "nonFederalDamOnFederalId":0, "designerNames":"CEMVK", "otherNames":"Lake Ouachita", "ownerNames":"USACE - Vicksburg District", "ownerTypeIds":"3", "primaryDamTypeId":8, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;5;6;8", "dsacId":3, "femaRegion":"6", "lastEapExcerDate":"2024-04-17T12:00:00.000Z", "dataUpdated":"2025-06-03T12:00:00.000Z", "usaceDistrict":"Vicksburg District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"080401", "doi_region":null, "doi_region_name":"Mississippi Basin", "doi_region_number":4, "thirtyYearAverage":2396.9229, "tenthPercentile":2317.3334, "ninetiethPercentile":2497.3322 }, "id":11092013, "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/11092013?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/11092013?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/11092013?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }