{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -71.6092, 42.1058 ] }, "properties":{ "provider":"NAE", "code":"WHD", "slug":"whd", "elevation":233.99, "horizontal_datum":"", "vertical_datum":"", "state":"MA", "kind":"PROJECT", "nearest_city":"Milford", "public_name":"West Hill Dam", "location_code":8191021, "nsid":null, "aliases":{ "NIDID":"MA00971", "CWMS Legacy Naming":"WHD", "CWMS Standard Naming":"WHD", "USGS Station Number":"01111200" }, "timeseries":[ { "tsid":"WHD.Stor.Inst.15Minutes.0.DCP-rev", "label":"Flood Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-08-25T21:30:00Z", "latest_value":33.6, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"WHD.Flow.Inst.15Minutes.0.DCP-rev", "label":"Outflow", "base_parameter":"Flow", "parameter":"Flow", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-08-25T21:30:00Z", "latest_value":4.04, "delta24h":null, "sort_order":7, "results":null }, { "tsid":"WHD.Precip.Inst.15Minutes.0.DCP-rev", "label":"Precipitation", "base_parameter":"Precip", "parameter":"Precip", "unit":"in", "unit_long_name":"Inches", "latest_time":"2026-08-25T21:30:00Z", "latest_value":32.83, "delta24h":null, "sort_order":16, "results":null }, { "tsid":"WHD.Temp-Air.Inst.15Minutes.0.DCP-rev", "label":"Air Temperature", "base_parameter":"Temp", "parameter":"Temp-Air", "unit":"F", "unit_long_name":"Fahrenheit", "latest_time":"2026-08-25T21:30:00Z", "latest_value":77.9, "delta24h":null, "sort_order":22, "results":null }, { "tsid":"WHD.Stage-TAILWATER.Inst.15Minutes.0.DCP-rev", "label":"Stage Tailwater", "base_parameter":"Stage", "parameter":"Stage-TAILWATER", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-08-25T21:30:00Z", "latest_value":1.14, "delta24h":null, "sort_order":5, "results":null }, { "tsid":"WHD.Stage-Pool.Inst.15Minutes.0.DCP-rev", "label":"Stage", "base_parameter":"Stage", "parameter":"Stage-Pool", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-08-25T21:30:00Z", "latest_value":2.09, "delta24h":null, "sort_order":4, "results":null }, { "tsid":"WHD.Flow-Inflow.Total.15Minutes.6Hours.DCP-rev", "label":"Inflow", "base_parameter":"Flow", "parameter":"Flow-Inflow", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-08-25T21:30:00Z", "latest_value":3.76, "delta24h":null, "sort_order":6, "results":null } ], "name":"West Hill Dam", "hasResopsAverages":"false", "nidId":"MA00971", "nidid":"", "levels":[ { "slug":"stage.bottom of normal", "label":"Bottom of Normal", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WHD.Stage-Pool.Inst.0.Bottom of Normal", "latest_value":0, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stage.spillway crest", "label":"Spillway Crest", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WHD.Stage-Pool.Inst.0.Spillway Crest", "latest_value":30, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stage.streambed", "label":"Streambed", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WHD.Stage-Pool.Inst.0.Streambed", "latest_value":0, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stage.top of dam", "label":"Top of Dam", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WHD.Stage-Pool.Inst.0.Top of Dam", "latest_value":48, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stage.top of flood", "label":"Top of Flood", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WHD.Stage-Pool.Inst.0.Top of Flood", "latest_value":30, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stage.top of normal", "label":"Top of Normal", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WHD.Stage-Pool.Inst.0.Top of Normal", "latest_value":3, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WHD.Stor.Inst.0.Top of Flood", "latest_value":12440, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" }, { "slug":"stor.top of normal", "label":"Top of Normal", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WHD.Stor.Inst.0.Top of Normal", "latest_value":30, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" } ], "id":550428, "associatedStructuresCount":1, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":48, "damLength":670, "distance":null, "drainageArea":28, "eapId":1, "dsacAssignedDate":"2022-08-11T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-12-20T12:00:00.000Z", "eapLastRevDate":"2020-03-13T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"MA00971", "oldFederalId":"MA00971", "hazardId":4, "hydraulicHeight":43, "inspectionAuthorityId":0, "inspectionDate":"2021-06-15T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":42.1059044310001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-71.6048819339999, "maxDischarge":8900, "maxStorage":29500, "nidHeight":48, "nidStorage":29500, "normalStorage":0, "numberOfLocks":0, "operationalStatusDate":"2022-08-11T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"West Hill Dam was constructed by the U.S. Army Corps of Engineers (USACE) in 1961 across the West River. This dam was built to hold water back during flood events to help reduce the risk of downstream flooding along the West and Blackstone Rivers. Dikes A, B, C and D, located west of the main dam, are also part of the project and were built to close off low points along the reservoir rim. Dikes A, B and C would impact the same area as the main dam and are therefore included as part of this description. Dike D, on the other hand, impacts a slightly different area than West Hill Dam and has been included under a separate description. West Hill Dam does not normally hold significant water outside of flood events. The pool is normally kept at a depth of approximately 2 feet. Since it began operations up to 2021, the dam has reduced damage caused by downstream flooding by approximately $119 million.\n\nThe dam is made of compacted earth fill and dumped rock fill with a concrete wall extending from the crest down to bedrock. The dam is approximately 5 stories (48 feet) high. The river flows through three concrete tunnels called conduits through the dam spillway. A dam\u2019s spillway is similar in concept to a sink overflow that prevents a sink bowl from completely overflowing. Metal gates in these tunnels are opened to allow water to pass and are closed when water needs to be stored during flood events. To maintain the structural integrity of the dam when the water level in the reservoir gets high, water can also be released across the dam\u2019s spillway. The spillway at West Hill Dam is located to the right of the dam and is a sloped concrete structure. It is approximately half the length of a football field (50 feet) and is approximately 2 stories lower than the dam (18 feet).\n\nDikes A, B and C are composed of compacted earth fill and dumped rock fill and vary from 8 to 14 feet in height. The tops of the dikes are all at the same elevation as the dam.", "riskCharSummary":"A risk assessment of West Hill Dam was last completed in 2021 and has identified the risks associated with the dam and Dikes A, B and C, as Very Low. This classification is based primarily on the very low population living downstream of the dam that could potentially be impacted by flooding due to failure of the dam and dikes as well as the low likelihood of failure of the dam and dikes and catastrophic flooding occurring. The dam and dikes significantly reduce the risk of flooding to the surrounding communities. However, they do not entirely eliminate the risk. The most likely scenario that could result in downstream flooding from West Hill Dam and Dikes A, B and C would be an uncontrolled high volume release of water from the dam\u2019s spillway during significant storm events. The amount of water being released could be great enough to cause flooding in downstream communities. Such higher releases from the spillway could create conditions similar to how the river might behave during a flood event if the dam did not exist.\n\nThere are three extremely unlikely, but far more devastating scenarios that would result in failure of the dam and downstream flooding: (1) A flood so large that the capacity of the dam and dikes to store water is exceeded and at least one of them is compromised, (2) water seeping through the earth embankment and/or the bedrock foundation resulting in voids in the dam as the soil erodes, potentially weakening the dam, and (3) a seismic event weakens the dam and it\u2019s foundation coupled with the occurrence of a very large flood that further compromises the dam. Were either of these events to occur, an uncontrolled surge of water would flow out of the reservoir, flooding downstream communities. \n\nWoonsocket, RI, is the major area in immediate danger in the event of the flood. Towns and cities both upstream and downstream of Woonsocket, including Uxbridge/Wheelockville, MA, and Pawtucket/Providence, RI would also be impacted, but less so. \n\nEven though extremely unlikely, if any of the scenarios described above were to occur, the downstream floodwater would be swift and deep, destroying buildings and key infrastructure, and 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 than flooding due to spillway discharges. In a worst-case scenario, water could be almost as high as a two-story building (between 6 and 15 feet in some areas).", "riskManagementMeasures":"No emergency situation currently exists at West Hill Dam and under normal circumstances, there is very low risk to the public. Should a crisis occur, we will use our expertise to quickly find a solution to resume normal operations. While we cannot completely eliminate risk, we will take actions to reduce the risks. We closely monitor the performance of West Hill Dam and will modify operations, if necessary, to lower 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 for the dam and dikes. We will also continue 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 so that necessary flood warnings may be issued in a timely manner. Regular maintenance and repairs are performed as needed to keep the dam functioning properly.", "riverName":"WEST RIVER", "separateStructuresCount":1, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":50, "stateFedId":"MA00971", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":48, "submitDate":"2023-02-16T17:25:30.677Z", "surfaceArea":1, "volume":329800, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1961, "congDist":"Congressional District 02, Massachusetts", "city":"UXBRIDGE", "county":"Worcester", "aiannh":null, "websiteUrl":"https://www.nae.usace.army.mil/Missions/Civil-Works/Flood-Risk-Management/Massachusetts/West-Hill/", "coreTypeIds":"3", "damTypeIds":"9;8", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":"3", "nonFederalDamOnFederalId":0, "designerNames":"CENAE", "otherNames":"Dry Reservoir", "ownerNames":"USACE - New England District", "ownerTypeIds":"3", "primaryDamTypeId":9, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;5", "dsacId":5, "femaRegion":"1", "lastEapExcerDate":"2024-04-05T12:00:00.000Z", "dataUpdated":"2025-03-17T12:00:00.000Z", "usaceDistrict":"New England District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"010900", "doi_region":null, "doi_region_name":"North Atlantic-Appalachian", "doi_region_number":1 }, "id":8191021, "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/8191021?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/8191021?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/8191021?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }