{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -71.9014, 41.945 ] }, "properties":{ "provider":"NAE", "code":"WTD", "slug":"wtd", "elevation":292.0, "horizontal_datum":"WGS84", "vertical_datum":"NGVD29", "state":"CT", "kind":"PROJECT", "nearest_city":"Webster", "public_name":"West Thompson Dam", "location_code":8203021, "nsid":null, "aliases":{ "NIDID":"CT00502", "CWMS Legacy Naming":"WTD", "CWMS Standard Naming":"WTD", "USGS Station Number":"01124151" }, "timeseries":[ { "tsid":"WTD.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":0.55, "delta24h":null, "sort_order":5, "results":null }, { "tsid":"WTD.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":1557.6, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"WTD.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":75.3, "delta24h":null, "sort_order":22, "results":null }, { "tsid":"WTD.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":40.66, "delta24h":null, "sort_order":6, "results":null }, { "tsid":"WTD.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":14.49, "delta24h":null, "sort_order":4, "results":null }, { "tsid":"WTD.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":41.7, "delta24h":null, "sort_order":16, "results":null }, { "tsid":"WTD.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":40.83, "delta24h":null, "sort_order":7, "results":null } ], "name":"West Thompson Dam", "hasResopsAverages":"false", "nidId":"CT00502", "nidid":"", "levels":[ { "slug":"stage.bottom of normal", "label":"Bottom of Normal", "parameter":"Stage-Pool", "base_parameter":"Stage", "tsid":"WTD.Stage-Pool.Inst.0.Bottom of Normal", "latest_value":0, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"stage.streambed", "label":"Streambed", "parameter":"Stage-Pool", "base_parameter":"Stage", 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"units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"WTD.Stor.Inst.0.Top of Flood", "latest_value":25600, "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":"WTD.Stor.Inst.0.Top of Normal", "latest_value":600, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" } ], "id":549839, "associatedStructuresCount":1, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":70, "damLength":2550, "distance":null, "drainageArea":174, "eapId":1, "dsacAssignedDate":"2017-07-12T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-12-20T12:00:00.000Z", "eapLastRevDate":"2020-04-16T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"CT00502", "oldFederalId":"CT00502", "hazardId":4, "hydraulicHeight":65, "inspectionAuthorityId":0, "inspectionDate":"2021-05-05T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":41.945915417, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-71.89861616, "maxDischarge":63000, "maxStorage":47800, "nidHeight":70, "nidStorage":47800, "normalStorage":1200, "numberOfLocks":0, "operationalStatusDate":"2017-07-12T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) built West Thompson Dam from 1963 to 1965 across the Quinebaug River. The dam holds back water during flood events to reduce the risk of downstream flooding on the Quinebaug and Thames Rivers. West Thompson Dam normally holds a 13-foot deep, permanent, conservation pool. The dam was built in response to the severe flooding that occurred in the region in 1936. Since it began operations through 2015, the dam has reduced damage caused by downstream flooding by more than $92.3 million.\n\nThe dam is made of compacted earth and rock fill and is approximately 7 stories (70 feet) high. A 12-foot diameter concrete pipe called a conduit passes through the dam. Metal gates at the upstream side of the conduit are opened to allow water to pass through the dam 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 spillway, a sloped concrete structure located on the right abutment of the dam. A spillway is similar in concept to a sink overflow that prevents a sink bowl from completely overflowing. The spillway is approximately the length of a football field and approximately two stories below the top of the dam. One dike (Reardon Road Dike), also composed of earth and rock fill, with an approximate height equivalent to 2 stories (19 feet) were constructed to close off a low area around the reservoir.", "riskCharSummary":"USACE completed a risk assessment of West Thompson Dam in 2016 and has classified the risks associated with the dam as Low. This classification is based primarily on the sizeable population living downstream of the dam that could experience catastrophic flooding in the very unlikely event of a failure of the dam. The dam significantly reduces the risk of flooding to surrounding communities. However, it does not entirely eliminate the risk. The most likely scenario that could result in downstream flooding from West Thompson Dam would be an uncontrolled high volume release of water from the dam's 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 also two extremely unlikely, but far more devastating scenarios that would result in failure of the dam and downstream flooding: (1) water from waves intermittently flowing over the earth embankment crest results in erosion of the dam crest, potentially weakening the dam, (2) water seeping through the earth embankment and its foundation results in voids in the dam as the soil erodes, potentially weakening the dam. Putnam, Danielson, and Jewett City, CT are the major areas in immediate danger in the event of the flood. Towns and cities further downstream would also be impacted, but less so. \n\nEven though very 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, you could see water greater than a one and half story building.", "riskManagementMeasures":"No emergency situation currently exists, or is about to occur, at West Thompson Dam. There is very low risk to the public under normal circumstances. 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 are taking actions to reduce the risks. We closely monitor the performance of West Thompson Dam and will modify operations if we feel there is 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. 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 so that necessary flood warnings may be issued in a timely manner. USACE is undertaking additional study to further understand the risk associated with West Thompson Dam, and what, if any, actions can be completed to reduce the risk.", "riverName":"QUINEBAUG RIVER", "separateStructuresCount":1, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":320, "stateFedId":"CT00502", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":70, "submitDate":"2023-02-16T17:25:31.226Z", "surfaceArea":200, "volume":1184900, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1965, "congDist":"Congressional District 02, Connecticut", "city":"PUTNAM", "county":"Windham", "aiannh":null, "websiteUrl":"https://www.nae.usace.army.mil/Missions/Civil-Works/Flood-Risk-Management/Connecticut/West-Thompson/", "coreTypeIds":null, "damTypeIds":"9;8", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":null, "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":null, "nonFederalDamOnFederalId":0, "designerNames":null, "otherNames":"West Thompson Lake", "ownerNames":"USACE - New England District", "ownerTypeIds":"3", "primaryDamTypeId":9, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;5", "dsacId":4, "femaRegion":"1", "lastEapExcerDate":"2024-04-05T12:00:00.000Z", "dataUpdated":"2024-12-20T12:00:00.000Z", "usaceDistrict":"New England District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"011000", "doi_region":null, "doi_region_name":"North Atlantic-Appalachian", "doi_region_number":1 }, "id":8203021, "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/8203021?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/8203021?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/8203021?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }