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"label":"Streambed", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Orwell_Dam.Stor.Inst.0.Streambed", "latest_value":150, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of conservation", "label":"Top of Conservation", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Orwell_Dam.Stor.Inst.0.Top of Conservation", "latest_value":8725, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of dam", "label":"Top of Dam", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Orwell_Dam.Stor.Inst.0.Top of Dam", "latest_value":28300, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Orwell_Dam.Stor.Inst.0.Top of Flood", "latest_value":14000, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of induced surcharge", "label":"Top of Induced Surcharge", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Orwell_Dam.Stor.Inst.0.Top of Induced Surcharge", "latest_value":17750, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":550434, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":10, "damLength":1355, "distance":30, "drainageArea":1820, "eapId":1, "dsacAssignedDate":"2014-07-29T12:00:00.000Z", "eapMeetsGuidelinesId":0, "emergencyContactsUpdated":"2024-11-14T12:00:00.000Z", "eapLastRevDate":"1992-02-01T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"MN00574", "oldFederalId":"MN00574", "hazardId":4, "hydraulicHeight":35, "inspectionAuthorityId":0, "inspectionDate":"2021-02-23T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":46.2171414250001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-96.179235559, "maxDischarge":20400, "maxStorage":20600, "nidHeight":60, "nidStorage":20600, "normalStorage":8050, "numberOfLocks":0, "operationalStatusDate":"2014-07-29T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"Orwell Dam is located about 7 miles southwest of Fergus Falls, Minnesota, in Ottertail County and on the Ottertail River. The U.S. Army Corps of Engineers constructed Orwell Dam, completed in 1953. The original purposes were flood control, water supply, and water quality (pollution abatement was primarily due to beet processing during low flow periods). The water supply and pollution abatement are no longer significant after technological changes, but they remain as secondary purposes. The conservation pool is maintained for fish & wildlife and recreation. Flood control is maximized by reservoir drawn down in early spring to provide storage for anticipated snowmelt runoff. The main components of the project are an earthen embankment, a combined gated spillway and outlet structure, and a downstream tailwater control structure. The earthen dam is 1,355 feet long and 47 feet high, and the elevation of the top of the earthen embankment is 1080 feet NAVD88. 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.)", "riskCharSummary":"Orwell dam has provided an average of $1.4 million annually in flood damage reduction benefits since it was placed into service, but it does not eliminate flood risk in the Ottertail River. Flood events may occur throughout the year, particularly during spring snowmelt and summer storms. Orwell is designed for extreme events where water must be released to protect the dam\u2019s integrity even though streams and rivers may have already reached or exceeded their capacity. The gated spillway is sized to discharge 24,000 cubic feet per second, which matches peak inflows during the probable maximum flood. Since the dam was constructed, the maximum outflows have been less than 2000 cubic feet per second. \n\nUSACE completed a risk assessment for Orwell Dam in 2020 that characterized the risk associated with the project as Low. Failure scenarios considered hydrologic adequacy, embankment overtopping due to inoperability of the spillway gate, and seepage in the spillway foundation. Life safety consequences derived from inundation mapping are mostly in Breckenridge and Wahpeton, both about 30 miles downstream.", "riskManagementMeasures":"USACE manages dam-related flood risks by continually monitoring the condition and health of the dam, prioritizing activities that will most impact the risks, and engaging upstream and downstream emergency managers and members of the public to raise awareness of the dam and support actions to prepare and be ready to respond in the case of a dam-related emergency. USACE works closely with local emergency managers to share what is known about the dam and support the development of local emergency and evacuation plans. USACE is continually taking steps to manage the risks to the public. Weather and streamflow forecast information is critical for operating the dam most effectively. The Corps of Engineers works closely with the National Weather Service to share real-time data and river models; and this information is used to minimize any flooding impacts to downstream communities. To manage dam safety risks, USACE has a routine program that inspects and monitors its dams regularly and implements short- and long-term actions on a prioritized basis when unacceptable risks are found at any of its dams. To meet safety standards for extreme floods, a parapet wall was added to the embankment and the tailwater control structure was added about 1000 feet downstream of the dam in 2001.", "riverName":"OTTER TAIL RIVER", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":1, "spillwayWidth":33, "stateFedId":"MN00574", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":60, "submitDate":"2023-02-16T17:25:27.831Z", "surfaceArea":805, "volume":168000, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1953, "congDist":"Congressional District 07, Minnesota", "city":"BRECKENRIDGE", "county":"Otter Tail", "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":"3", "nonFederalDamOnFederalId":0, "designerNames":"CEMVP", "otherNames":"Orwell Lake", "ownerNames":"USACE - St. Paul District", "ownerTypeIds":"3", "primaryDamTypeId":8, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;12;4;5", "dsacId":4, "femaRegion":"5", "lastEapExcerDate":"2023-04-14T12:00:00.000Z", "dataUpdated":"2024-11-14T12:00:00.000Z", "usaceDistrict":"St. Paul District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"090201", "doi_region":null, "doi_region_name":"Great Lakes", "doi_region_number":3 }, "id":2000016, "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/2000016?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/2000016?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/2000016?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }