{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -79.27787, 40.92172 ] }, "properties":{ "provider":"LRP", "code":"Mahoning", "slug":"mahoning", "elevation":0.0, "horizontal_datum":"WGS84", "vertical_datum":"NAVD88", "state":"PA", "kind":"PROJECT", "nearest_city":"Harrison Township", "public_name":"Mahoning Creek Lake", "location_code":16701111, "nsid":null, "aliases":{ "NIDID":"PA00107" }, "timeseries":[ { "tsid":"Mahoning-Outflow.Stage.Inst.1Hour.0.OBS", "label":"Stage", "base_parameter":"Stage", "parameter":"Stage", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":3.96, "delta24h":null, "sort_order":4, "results":null }, { "tsid":"Mahoning-Lake.Stor.Inst.1Hour.0.OBS", "label":"Conservation Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":9663.63, "delta24h":null, "sort_order":13, "results":null }, { "tsid":"Mahoning-Outflow.Stage.Inst.1Hour.0.OBS", "label":"Stage Tailwater", "base_parameter":"Stage", "parameter":"Stage", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":3.96, "delta24h":null, "sort_order":5, "results":null }, { "tsid":"Mahoning-Outflow.Flow.Inst.1Hour.0.OBS", "label":"Outflow", "base_parameter":"Flow", "parameter":"Flow", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-04-14T21:00:00Z", "latest_value":1107.37, "delta24h":null, "sort_order":7, "results":null }, { "tsid":"Mahoning-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":607.86, "delta24h":null, "sort_order":6, "results":null }, { "tsid":"Mahoning-Lake.Precip-Inc.Total.1Hour.1Hour.OBS", "label":"Precipitation", "base_parameter":"Precip", "parameter":"Precip-Inc", "unit":"in", "unit_long_name":"Inches", "latest_time":"2026-04-14T21:00:00Z", "latest_value":0.0, "delta24h":null, "sort_order":16, "results":null }, { "tsid":"Mahoning-Lake.Stor.Inst.1Hour.0.OBS", "label":"Flood Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":9663.63, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"Mahoning-Lake.Elev.Inst.1Hour.0.OBS", "label":"Elevation", "base_parameter":"Elev", "parameter":"Elev", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":1097.63, "delta24h":null, "sort_order":1, "results":null } ], "name":"Mahoning Creek Lake", "hasResopsAverages":"false", "nidId":"PA00107", "nidid":"", "levels":[ { "slug":"elev.minimum", "label":"Minimum", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Minimum", "latest_value":1074.28, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.streambed", "label":"Streambed", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Streambed", "latest_value":1005.3, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of conservation", "label":"Top of Conservation", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Top of Conservation", "latest_value":1074.28, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of dam", "label":"Top of Dam", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Top of Dam", "latest_value":1168.6, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of flood", "label":"Top of Flood", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Top of Flood", "latest_value":1161.14, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of full", "label":"Top of Full", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Top of Full", "latest_value":1161.14, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of inactive", "label":"Top of Inactive", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Mahoning.Elev.Inst.0.Top of Inactive", "latest_value":1074.28, "units":"ft", "units_long_name":"Feet" }, { "slug":"stor.minimum", "label":"Minimum", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Mahoning.Stor.Inst.0.Minimum", "latest_value":4500, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.streambed", "label":"Streambed", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Mahoning.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":"Mahoning.Stor.Inst.0.Top of Conservation", "latest_value":4500, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of dam", "label":"Top of Dam", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Mahoning.Stor.Inst.0.Top of Dam", "latest_value":93649, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Mahoning.Stor.Inst.0.Top of Flood", "latest_value":74200, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of full", "label":"Top of Full", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Mahoning.Stor.Inst.0.Top of Full", "latest_value":74200, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of inactive", "label":"Top of Inactive", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Mahoning.Stor.Inst.0.Top of Inactive", "latest_value":4500, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":550028, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":null, "damLength":926, "distance":5, "drainageArea":340, "eapId":1, "dsacAssignedDate":"2023-11-08T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-10-25T12:00:00.000Z", "eapLastRevDate":null, "enforcementAuthorityId":0, "federalId":"PA00107", "oldFederalId":"PA00107", "hazardId":4, "hydraulicHeight":162, "inspectionAuthorityId":0, "inspectionDate":"2022-11-10T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":40.9217878550001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-79.278047501, "maxDischarge":103000, "maxStorage":94000, "nidHeight":162, "nidStorage":94000, "normalStorage":9550, "numberOfLocks":0, "operationalStatusDate":"2023-11-08T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) constructed Mahoning Dam across Mahoning Creek in 1941 to hold back water during flood events to reduce the risk of downstream flooding in the low-lying communities including Putneyville, Kittanning, Ford City, the greater Pittsburgh area, and additional towns on the Allegheny and Ohio Rivers in Pennsylvania, West Virginia and Ohio. The dam is located about 23 miles upstream of the confluence between Allegheny River and Mahoning Creek. Mahoning Dam has reduced flood damage by more than an estimated $800 million since the start of operations. The reservoir stores rainfall to maintain downstream flow within the downstream river banks and releases water after flood events and in the late summer and fall; provides water to a non-federal hydropower facility; and provides numerous opportunities for recreation. Mahoning Dam is composed of concrete and has a maximum height of 166.5 feet and a length of 926 feet. The dam has five spillway gates designed to release a large volume of water during significant rainfall events to reduce the possibility that water from the reservoir will overtop the dam. The gates are composed of steel, and each is 29 feet high by 30 feet wide. The gates are supported by concrete piers, which also support the bridge structure at the top of the dam.", "riskCharSummary":"The most recent risk assessment for Mahoning Dam was completed in 2022, which characterized the risk posed by the dam as very low. However, an extremely intense rainfall could fill the reservoir beyond its intended capacity. Also, the concrete at the surface of the dam and in the piers that support the spillway gates is in poor condition. This condition is not believed to affect the stability of the concrete dam but could increase the likelihood that one or more of the concrete piers could move downstream, which could release a large volume of water downstream. The nearest town downstream of Mahoning Dam is Putneyville, Pennsylvania and large populations are situated in Kittanning, Ford City, Pennsylvania. The greater Pittsburgh area, and additional towns on the Allegheny and Ohio Rivers could be affected by flooding related to flow from Mahoning Dam in the event of extreme rainfall. Although the dam reduces the risk of flooding to these communities, it does not eliminate flooding. The most likely scenario resulting in downstream flooding from Mahoning Dam would be high-volume flow of water through the dam\u2019s spillway, which has never happened since the start of dam operations in 1941) during an unusually large and intense storm event. Alternatively, if one of the piers that supports the spillway gates This high-volume release could cause flooding within Mahoning Creek that would be similar to conditions that would exist if Mahoning Dam had not been constructed.\n\nA less likely and more devastating flooding scenario exists: an extreme rainfall event that results in reservoir water overtopping the dam, eroding the bedrock upon which the dam is founded, which could result in portions of the concrete dam moving downstream. If this were to happen, the large volume of water in the Mahoning Creek Reservoir would cause severe flooding in the Mahoning Creek valley and significant flooding in the Allegheny River valley.\n\nIn either scenario, a large surge of water would flow out of the reservoir, flooding downstream communities. Communities, including Putneyville, that are closer to the dam, are in more immediate danger of a significant flood event and may have little advanced warning. Cities and communities further downstream of the dam, such as Kittanning, Ford City, communities in metropolitan Pittsburgh, and communities on the Allegheny and Ohio Rivers have larger populations and possibly less awareness of the dam but will have more warning. \n\nWith either of the scenarios described above, the downstream floodwater would be swift and deep, possibly overflowing banks on the Allegheny and Ohio Rivers, destroying buildings and infrastructure. Anyone caught unaware and/or unable to evacuate could perish. In the most likely dam breach scenario, the water depth, property damage, and lives lost would likely be far greater.", "riskManagementMeasures":"USACE will continue to work closely with state and local emergency managers, conduct emergency exercises and incorporate any new information into our emergency action plans. We will continue rigorous monitoring and surveillance of the dam and will do so more frequently during high-water events. Rainfall forecasts and reservoir levels are routinely monitored and if a high-water event is forecast, we will promptly inform local and state emergency managers so that they can take protective actions, make flood warnings, and prepare for emergency responses. We will work with local communities to provide opportunities to engage with residents to help them understand how they can better prepare for a potential flood. In partnership with the US Geologic Survey and the National Weather Service, information on current lake levels at the Mahoning Creek Lake is available to the public via the internet at: \n\nhttps://waterdata.usgs.gov/nwis/uv/?site_no=03035500", "riverName":"MAHONING CREEK", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":1, "spillwayWidth":150, "stateFedId":"PA00107", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":162, "submitDate":"2023-02-16T17:25:22.456Z", "surfaceArea":280, "volume":400200, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1941, "congDist":"Congressional District 15, Pennsylvania", "city":"PUTNEYVILLE", "county":"Armstrong", "aiannh":null, "websiteUrl":"https://www.usace.army.mil/Missions/Civil-Works/Dam-Safety-Program/Article/2870967/dam-safety-program/", "coreTypeIds":"2", "damTypeIds":"9", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":"1", "nonFederalDamOnFederalId":0, "designerNames":"CELRP", "otherNames":"Mahoning Creek Lake", "ownerNames":"USACE - Pittsburgh District", "ownerTypeIds":"3", "primaryDamTypeId":9, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;4;5", "dsacId":5, "femaRegion":"3", "lastEapExcerDate":"2025-04-04T12:00:00.000Z", "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":"050100", "doi_region":null, "doi_region_name":"North Atlantic-Appalachian", "doi_region_number":1 }, "id":16701111, "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/16701111?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/16701111?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/16701111?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }