{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -84.15074, 39.02214 ] }, "properties":{ "provider":"LRL", "code":"WHHarsha", "slug":"whharsha", "elevation":729.0, "horizontal_datum":"NAD27", "vertical_datum":"NGVD29", "state":"OH", "kind":"PROJECT", "nearest_city":"Woodlawn, OH", "public_name":"William H. 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"units_long_name":"Acre-feet" }, { "slug":"stor.top of dam", "label":"Top of Dam", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WHHarsha.Stor.Inst.0.Top of Dam", "latest_value":413111, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WHHarsha.Stor.Inst.0.Top of Flood", "latest_value":284500, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of normal", "label":"Top of Normal", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WHHarsha.Stor.Inst.0.Top of Normal", "latest_value":82200, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of overflow", "label":"Top of Overflow", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WHHarsha.Stor.Inst.0.Top of Overflow", "latest_value":284500, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":550169, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":null, "damLength":1450, "distance":5, "drainageArea":342, "eapId":1, "dsacAssignedDate":"2016-05-05T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2025-02-28T12:00:00.000Z", "eapLastRevDate":"2019-09-05T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"OH00929", "oldFederalId":"OH00929", "hazardId":4, "hydraulicHeight":196, "inspectionAuthorityId":0, "inspectionDate":"2020-08-03T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":39.0227750290001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-84.150561755, "maxDischarge":211000, "maxStorage":294800, "nidHeight":205, "nidStorage":294800, "normalStorage":92600, "numberOfLocks":0, "operationalStatusDate":"2016-05-05T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) completed William H. Harsha Lake in 1978. The dam located on the East Fork of the Little Miami River, 21.3 miles above the junction with the Little Miami River near Terrace Park, Ohio. The project is located in southwestern Ohio about 25 miles east of Cincinnati, Ohio, approximately 7.0 miles upstream from Batavia and 3.5 miles east of Amelia, Ohio. The dam project consists of a 1,460-foot-long earth and rock filled embankment with a maximum height of 201 feet, a 2,622-foot-long saddle dam, a gate-controlled outlet works, an open cut spillway, and a dike constructed as part of the right spillway bank. The project reduces flood damages along 21.3 miles of the East Fork of the Little Miami River and along the main channel of the Little Miami River up to its confluence with the Ohio River. The drainage area of the dam is 342 square miles. The record pool occurred in May 2011 and reached elevation 776.85 ft NAVD88.", "riskCharSummary":"USACE completed a risk assessment for William H. Harsha Lake in May 2016 that characterizes the risk of the project as a Dam Safety Action Classification (DSAC) 4 which is considered Low relative to the dams USACE owns and operates. The dam significantly reduces the risk of flooding to downstream communities however, it does not eliminate the risk completely. Even when the dam operates as intended, downstream flooding could still occur if a very large rainfall event were to result in unusually large quantities of water to flow through the dam spillway. There is also an unlikely, but far more devastating scenario that would produce significant flooding which is internal erosion of the dam\u2019s or the saddle dam\u2019s embankment during a period of high reservoir levels that could lead to breach of the dam. In these scenarios, an uncontrolled surge of water could flow out of the reservoir, resulting in potentially deadly flooding along the Little Miami River.\n\nIf a dam failure occurred, water from the reservoir would flood downstream communities. The largest impacts would be to the communities of Batavia, Milford, Newtown, and Cincinnati Ohio. Critical infrastructure that could be impacted by flood waters includes schools, fire stations, police stations, airports, and electric substations. Once flooding reaches the confluence of the Ohio and the Little Miami Rivers, flood waters would be primarily contained within the Ohio River. However, some areas along the Ohio River adjacent to the Little Miami River could be inundated.", "riskManagementMeasures":"USACE is continuously taking steps to reduce the risk to the public. This includes working closely with local emergency managers, regularly updating the Emergency Action Plan, and conducting emergency exercises with state and local response teams. USACE utilizes the latest forecast, and stream gauge information and coordinates closely with the National Weather Service concerning conditions both upstream and downstream of the dam including inflow, outflow, and precipitation. Rainfall forecasts are used to determine when high pool events may occur. USACE regularly inspects and monitors instruments to check the health of the dam. The frequency of these checks increases when the lake level rises. This ensures that the structure is performing as designed and could help detect any areas of potential concern. Regular maintenance and repairs are performed as needed to keep the dam functioning properly.", "riverName":"EAST FORK OF LITTLE MIAMI", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":985, "stateFedId":"OH00929", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":205, "submitDate":"2023-12-06T14:56:50.222Z", "surfaceArea":2160, "volume":5300000, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1973, "congDist":"Congressional District 02, Ohio", "city":"BATAVIA", "county":"Clermont", "aiannh":null, "websiteUrl":"https://www.usace.army.mil/Missions/Civil-Works/Dam-Safety-Program/Article/2870967/dam-safety-program/", "coreTypeIds":"3", "damTypeIds":"5;8", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":"3", "nonFederalDamOnFederalId":0, "designerNames":"CELRL", "otherNames":"William H. Harsha Lake", "ownerNames":"USACE - Louisville District", "ownerTypeIds":"3", "primaryDamTypeId":5, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;12;5;8", "dsacId":4, "femaRegion":"5", "lastEapExcerDate":"2025-02-28T12:00:00.000Z", "dataUpdated":"2025-06-18T12:00:00.000Z", "usaceDistrict":"Louisville District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"050902", "doi_region":null, "doi_region_name":"Great Lakes", "doi_region_number":3, "thirtyYearAverage":112.343, "tenthPercentile":103.0568, "ninetiethPercentile":129.5494 }, "id":1199109, "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/1199109?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/1199109?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/1199109?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }