{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -76.75381, 39.92263 ] }, "properties":{ "provider":"NAB", "code":"Indian Rock", "slug":"indian%20rock", "elevation":300.0, "horizontal_datum":"WGS84", "vertical_datum":"LOCAL", "state":"PA", "kind":"PROJECT", "nearest_city":"York", "public_name":"Indian Rock Dam", "location_code":1123020, "nsid":null, "aliases":{ "USGS Station Number":"01574700", "CWMS Legacy Naming":"Indian Rock", "CWMS Standard Naming":"Indian Rock", "NIDID":"PA00007", "CBT Station ID":"ctp", "SHEF Location ID":"YRKP1", "DCP Platform ID":"CE59BD90" }, "timeseries":[ { "tsid":"Indian Rock.Precip.Inst.15Minutes.0.Best-NAB", "label":"Precipitation", "base_parameter":"Precip", "parameter":"Precip", "unit":"in", "unit_long_name":"Inches", "latest_time":"2026-04-14T22:00:00Z", "latest_value":8.29, "delta24h":null, "sort_order":16, "results":null }, { "tsid":"Indian Rock.Elev.Inst.15Minutes.0.Best-NAB", "label":"Elevation", "base_parameter":"Elev", "parameter":"Elev", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":372.59, "delta24h":null, "sort_order":1, "results":null }, { "tsid":"Indian Rock.Flow-Out.Inst.15Minutes.0.Best-NAB-Computed", "label":"Outflow", "base_parameter":"Flow", "parameter":"Flow-Out", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-04-14T12:00:00Z", "latest_value":45.11, "delta24h":null, "sort_order":7, "results":null }, { "tsid":"Indian Rock.Stor.Inst.15Minutes.0.Best-NAB", "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":0.0, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"Indian Rock.%-FloodControl.Inst.15Minutes.0.Best-NAB-Computed", "label":"Percent Flood Pool", "base_parameter":"%", "parameter":"%-FloodControl", "unit":"%", "unit_long_name":"Percent", "latest_time":"2026-04-14T12:00:00Z", "latest_value":0.0, "delta24h":null, "sort_order":12, "results":null }, { "tsid":"Indian Rock.Temp-Air.Inst.15Minutes.0.Best-NAB", "label":"Air Temperature", "base_parameter":"Temp", "parameter":"Temp-Air", "unit":"F", "unit_long_name":"Fahrenheit", "latest_time":"2026-04-14T22:00:00Z", "latest_value":86.2, "delta24h":null, "sort_order":22, "results":null } ], "name":"Indian Rock Dam", "hasResopsAverages":"false", "nidId":"PA00007", "nidid":"", "levels":[ { "slug":"elev.25% flood storage", "label":"25% Flood Storage", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.25% Flood Storage", "latest_value":413.55, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.5% flood storage", "label":"5% Flood Storage", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.5% Flood Storage", "latest_value":398.32, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.50% flood storage", "label":"50% Flood Storage", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.50% Flood Storage", "latest_value":423.09, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.maximum", "label":"Maximum", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Maximum", "latest_value":451.2, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.record", "label":"Record", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Record", "latest_value":436.44, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.spillway crest", "label":"Spillway Crest", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Spillway Crest", "latest_value":435, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.streambed", "label":"Streambed", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Streambed", "latest_value":369.2, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of conservation", "label":"Top of Conservation", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Top of Conservation", "latest_value":370, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of dam", "label":"Top of Dam", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Top of Dam", "latest_value":452.2, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of flood control", "label":"Top of Flood Control", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Top of Flood Control", "latest_value":435, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of inactive", "label":"Top of Inactive", "parameter":"Elev", "base_parameter":"Elev", "tsid":"Indian Rock.Elev.Inst.0.Top of Inactive", "latest_value":370, "units":"ft", "units_long_name":"Feet" }, { "slug":"stor.streambed", "label":"Streambed", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Indian Rock.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":"Indian Rock.Stor.Inst.0.Top of Conservation", "latest_value":0, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of dam", "label":"Top of Dam", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Indian Rock.Stor.Inst.0.Top of Dam", "latest_value":60479.46, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood control", "label":"Top of Flood Control", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Indian Rock.Stor.Inst.0.Top of Flood Control", "latest_value":27657.45, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of inactive", "label":"Top of Inactive", "parameter":"Stor", "base_parameter":"Stor", "tsid":"Indian Rock.Stor.Inst.0.Top of Inactive", "latest_value":0, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":549974, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":83, "damLength":1000, "distance":null, "drainageArea":94, "eapId":1, "dsacAssignedDate":"2024-02-21T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2022-03-04T12:00:00.000Z", "eapLastRevDate":"2022-03-04T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"PA00007", "oldFederalId":"PA00007", "hazardId":4, "hydraulicHeight":76, "inspectionAuthorityId":0, "inspectionDate":"2023-03-06T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":39.9236526620001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-76.754503299, "maxDischarge":62000, "maxStorage":48000, "nidHeight":83, "nidStorage":48000, "normalStorage":0, "numberOfLocks":0, "operationalStatusDate":"2009-05-12T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) built Indian Rock Dam in 1942 to reduce the risk of flooding to downstream communities by storing water during major flood events. It is located on the Main Branch of Codorus Creek in York County, PA, at the confluence with the South Branch Codorus Creek. The dam is approximately two miles upstream of York, Pennsylvania, and fifteen miles upstream of the confluence with the Susquehanna River. The dam consists of an earthen embankment which creates a lake only during storm events. Flow discharges through a conduit in the abutment of the dam and gates control the releases when there is a lake. The project also includes an ungated spillway which can release large flows during significant flood events.", "riskCharSummary":"Although Indian Rock Dam reduces the risk of flooding to downstream communities, it does not eliminate the risk of flooding. The most likely scenario that could result in downstream flooding would be a high-volume release of water from the dam\u2019s spillway during significant storm events. To maintain the structural integrity of the dam when the water level in the reservoir gets high, the spillway releases water to Codorus Creek. The amount of water being released could be great enough to cause flooding in downstream communities. Such higher releases from the dam could create conditions similar to how the river might behave if the dam did not exist.\n\nThere are also unlikely, but far more devastating scenarios involving breach of the dam that would produce significant flooding. This could involve situations such as: a rare, extreme rainfall event resulting in water flowing over the earthen dam, eroding the dam and leading to a breach of the dam; or unexpected behavior of seepage through the dam, eroding soil from within the embankment and leading to a breach of the dam. If a breach were to occur, an uncontrolled surge of water would flow out of the reservoir, flooding downstream communities. York, Grantley and adjacent communities are in the most immediate danger in the event of a flood. Other communities along the Codorus Creek would also be impacted.\n\nIn any of the scenarios described above, the downstream floodwater would be swift and deep, overflowing levees and destroying buildings and key infrastructure. Those caught unaware and/or unable to evacuate could perish. In the less likely dam breach scenarios, the water depth, property damage, and lives lost would likely be far greater.", "riskManagementMeasures":"The U.S. Army Corps of Engineers (USACE) performs ongoing activities to ensure the integrity of Indian Rock Dam and to manage and reduce risk to the downstream communities. The dam is well-maintained, inspected, and monitored. The frequency of inspection and monitoring increases during high water events. USACE regularly updates the Emergency Action Plan for the dam and performs emergency response exercises with Federal, state, and local emergency managers to remain prepared to respond to flood events affecting the dam. USACE also closely follows rainfall forecasts to determine when high water events may occur to provide information for any necessary flood warnings.", "riverName":"CODORUS CREEK", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":461, "stateFedId":"PA00007", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":83, "submitDate":"2022-10-31T12:39:54.300Z", "surfaceArea":0, "volume":539400, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1942, "congDist":"Congressional District 10, Pennsylvania", "city":"YORK", "county":"York", "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":"2", "nonFederalDamOnFederalId":0, "designerNames":"CENAB", "otherNames":null, "ownerNames":"USACE - Baltimore District", "ownerTypeIds":"3", "primaryDamTypeId":5, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9", "dsacId":3, "femaRegion":"3", "lastEapExcerDate":"2024-09-16T12:00:00.000Z", "dataUpdated":"2025-01-30T12:00:00.000Z", "usaceDistrict":"Baltimore District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"020503", "doi_region":null, "doi_region_name":"North Atlantic-Appalachian", "doi_region_number":1 }, "id":1123020, "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/1123020?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/1123020?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/1123020?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }