{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -81.07906, 41.15614 ] }, "properties":{ "provider":"LRP", "code":"MJKirwan", "slug":"mjkirwan", "elevation":0.0, "horizontal_datum":"WGS84", "vertical_datum":"NAVD88", "state":"OH", "kind":"PROJECT", "nearest_city":"Ravenna", "public_name":"Michael J Kirwan Dam & Reservoir", "location_code":17023111, "nsid":null, "aliases":{ "NIDID":"OH00030" }, "timeseries":[ { "tsid":"MJKirwan-Lake.Flow-Inflow-Comp.Inst.1Hour.0.A2W", "label":"Inflow", "base_parameter":"Flow", "parameter":"Flow-Inflow-Comp", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-04-14T18:00:00Z", "latest_value":254.69, "delta24h":null, "sort_order":6, "results":null }, { "tsid":"MJKirwan-Outflow.Stage.Inst.1Hour.0.OBS", "label":"Stage Tailwater", "base_parameter":"Stage", "parameter":"Stage", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":7.6, "delta24h":null, "sort_order":5, "results":null }, { "tsid":"MJKirwan-Lake.Stor.Inst.1Hour.0.OBS", "label":"Conservation Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":59659.37, "delta24h":null, "sort_order":13, "results":null }, { "tsid":"MJKirwan-Outflow.Precip-Inc.Total.1Hour.1Hour.OBS", "label":"Precipitation", "base_parameter":"Precip", "parameter":"Precip-Inc", "unit":"in", "unit_long_name":"Inches", "latest_time":"2026-04-14T22:00:00Z", "latest_value":0.0, "delta24h":null, "sort_order":16, "results":null }, { "tsid":"MJKirwan-Lake.Stor.Inst.1Hour.0.OBS", "label":"Flood Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":59659.37, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"MJKirwan-Outflow.Flow.Inst.1Hour.0.OBS", "label":"Outflow", "base_parameter":"Flow", "parameter":"Flow", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-04-14T22:00:00Z", "latest_value":539.58, "delta24h":null, "sort_order":7, "results":null }, { "tsid":"MJKirwan-Lake.Elev.Inst.1Hour.0.OBS", "label":"Elevation", "base_parameter":"Elev", "parameter":"Elev", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":986.15, "delta24h":null, "sort_order":1, "results":null }, { "tsid":"MJKirwan-Outflow.Stage.Inst.1Hour.0.OBS", "label":"Stage", "base_parameter":"Stage", "parameter":"Stage", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":7.6, "delta24h":null, "sort_order":4, "results":null } ], "name":"Michael J Kirwan Dam & Reservoir", "hasResopsAverages":"false", "nidId":"OH00030", "nidid":"", "levels":[ { "slug":"elev.minimum", "label":"Minimum", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Minimum", "latest_value":950.51, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.streambed", "label":"Streambed", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Streambed", "latest_value":927.3, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of conservation", "label":"Top of Conservation", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Top of Conservation", "latest_value":984.8, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of dam", "label":"Top of Dam", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Top of Dam", "latest_value":1010.3, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of flood", "label":"Top of Flood", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Top of Flood", "latest_value":992.55, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of full", "label":"Top of Full", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Top of Full", "latest_value":992.55, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of inactive", "label":"Top of Inactive", "parameter":"Elev", "base_parameter":"Elev", "tsid":"MJKirwan.Elev.Inst.0.Top of Inactive", "latest_value":950.51, "units":"ft", "units_long_name":"Feet" }, { "slug":"stor.minimum", "label":"Minimum", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Minimum", "latest_value":3800, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.streambed", "label":"Streambed", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Streambed", "latest_value":0, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of conservation", "label":"Top of Conservation", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Top of Conservation", "latest_value":56040.79, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of dam", "label":"Top of Dam", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Top of Dam", "latest_value":150253, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Top of Flood", "latest_value":78700, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of full", "label":"Top of Full", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Top of Full", "latest_value":78700, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of inactive", "label":"Top of Inactive", "parameter":"Stor", "base_parameter":"Stor", "tsid":"MJKirwan.Stor.Inst.0.Top of Inactive", "latest_value":3800, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":550162, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":null, "damLength":9900, "distance":null, "drainageArea":81, "eapId":1, "dsacAssignedDate":"2018-07-11T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-10-25T12:00:00.000Z", "eapLastRevDate":null, "enforcementAuthorityId":0, "federalId":"OH00030", "oldFederalId":"OH00030", "hazardId":4, "hydraulicHeight":77, "inspectionAuthorityId":0, "inspectionDate":"2021-05-04T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":41.1565397250001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-81.079312006, "maxDischarge":38500, "maxStorage":124000, "nidHeight":83, "nidStorage":124000, "normalStorage":56700, "numberOfLocks":0, "operationalStatusDate":"2018-07-11T12:00:00.000Z", "operationalStatusId":2, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) built Michael J Kirwan Dam in 1966 across the Mahoning River to hold back water during flood events to reduce the risk of downstream flooding on the Mahoning, Beaver, and Ohio Rivers. Since it went into operation, the dam has reduced damage caused by downstream flooding by more than an estimated $1 billion. The reservoir also serves to store rainfall from late winter through early summer to augment flow during the drier late-summer and early-autumn months, provide water supply to downstream communities, and is used for recreational purposes. The dam is composed of an earthen embankment that is a maximum of 83 feet high and is 2 miles long. The reservoir levels are managed to approved levels throughout the year by means of a concrete conduit that discharges water to the downstream Mahoning River. A concrete spillway is situated alongside the dam to release reservoir water when levels get high. The spillway reduces the likelihood that the earthen dam could be overtopped and damaged.", "riskCharSummary":"Although Michael J Kirwan Dam reduces the risk of flooding to downstream communities, the dam does not eliminate the risk of flooding. The most recent risk assessment was completed in 2018, which characterized the risk posed by the dam as moderate. The most likely scenario that could result in downstream flooding from Michael J Kirwan Dam would be an uncontrolled high-volume release of water from the dam\u2019s spillway during significant storm events. The frequency and amount of water being released could be great enough to cause flooding in downstream communities. Although this has not happened since the dam was constructed, such flooding could be similar to how the river might behave if the dam did not exist.\n\nThere are several other unlikely, but far more devastating scenarios that could produce significant flooding if the reservoir level rises to a level higher than it has ever been: 1. the concrete spillway could collapse if the soil beneath the spillway erodes and cannot support the concrete spillway, 2. reservoir water flowing along cracks through the uppermost part of the soil embankment could erode the surrounding embankment soils, 3. water flowing along the concrete conduit could erode the surrounding soils, and 4. the dam crest and downstream embankment soils could erode if the reservoir level gets high enough and wind creates large waves that wash over the dam crest. An extreme rainfall event would be needed to trigger any of these events. There is uncertainty in how the dam and its spillway would perform in the events described above since the reservoir level has never been risen to the spillway level. If any of these events were to occur, an uncontrolled surge of water would flow out of the reservoir, flooding downstream communities. In Ohio, Niles, Newton Falls, Warren, and adjacent communities located in the valley below the dam are in more immediate danger in the event of a flood. Towns and cities further downstream, including Youngstown Ohio and New Castle and Beaver Falls in Pennsylvania, could experience flooding, but will also have greater warning times, should a flood occur.\n\nIn any of the scenarios described above, the downstream floodwater would be swift and deep, destroying buildings and key infrastructure, and anyone caught unaware and/or unable to evacuate could perish. In the less likely dam breach scenario, the water depth, property damage, and lives lost would likely be far greater.", "riskManagementMeasures":"To ensure we are taking all steps to reduce the risk to the public, we will continue to work closely with state and local emergency managers, conducting emergency exercises, and incorporate any new information into our emergency action plan. We will also continue our rigorous monitoring and surveillance of the dam, especially during high water events. We closely follow rainfall forecasts to determine when high water events may occur to provide information for any necessary flood warnings. We will work with local communities to provide opportunities to engage with local residents to help them understand how they can better prepare for a flood. In partnership with the US Geologic Survey and the National Weather Service, information on current and forecasted lake levels at Pittsburgh District reservoirs are available to the public via the internet at: \nhttps://www.lrp.usace.army.mil/Portals/72/docs/WaterManagement/ResSumPlots.pdf.", "riverName":"WEST BRANCH OF THE MAHONING", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":300, "stateFedId":"OH00030", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":83, "submitDate":"2023-02-16T17:25:42.245Z", "surfaceArea":2650, "volume":3432192, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1966, "congDist":"Congressional District 14, Ohio", "city":"WAYLAND", "county":"Portage", "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":"CELRP", "otherNames":"Michael J Kirwan Reservoir", "ownerNames":"USACE - Pittsburgh District", "ownerTypeIds":"3", "primaryDamTypeId":8, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;12", "dsacId":3, "femaRegion":"5", "lastEapExcerDate":"2025-04-16T12:00:00.000Z", "dataUpdated":"2025-05-29T12:00:00.000Z", "usaceDistrict":"Pittsburgh District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"050301", "doi_region":null, "doi_region_name":"Great Lakes", "doi_region_number":3 }, "id":17023111, "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/17023111?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/17023111?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/17023111?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }