{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -71.9878, 42.8939 ] }, "properties":{ "provider":"NAE", "code":"EMD", "slug":"emd", "elevation":904.0, "horizontal_datum":"WGS84", "vertical_datum":"", "state":"NH", "kind":"PROJECT", "nearest_city":"Keene", "public_name":"Edward MacDowell Dam", "location_code":8059021, "nsid":null, "aliases":{ "NIDID":"NH00005", "CWMS Legacy Naming":"EMD", "CWMS Standard Naming":"EMD", "USGS Station Number":"01083000" }, "timeseries":[ { "tsid":"EMD.Stage-TAILWATER.Inst.15Minutes.0.DCP-rev", "label":"Stage Tailwater", "base_parameter":"Stage", "parameter":"Stage-TAILWATER", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-08-25T22:00:00Z", "latest_value":2.39, "delta24h":null, "sort_order":5, "results":null }, { "tsid":"EMD.Flow-Inflow.Total.15Minutes.6Hours.DCP-rev", "label":"Inflow", "base_parameter":"Flow", "parameter":"Flow-Inflow", "unit":"cfs", "unit_long_name":"Cubic feet per second", 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Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-08-25T22:00:00Z", "latest_value":102.38, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"EMD.Temp-Air.Inst.15Minutes.0.DCP-rev", "label":"Air Temperature", "base_parameter":"Temp", "parameter":"Temp-Air", "unit":"F", "unit_long_name":"Fahrenheit", "latest_time":"2026-08-25T22:15:00Z", "latest_value":71.47, "delta24h":null, "sort_order":22, "results":null } ], "name":"Edward MacDowell Dam", "hasResopsAverages":"false", "nidId":"NH00005", "nidid":"", "levels":[ { "slug":"elev.bottom of normal", "label":"Bottom of Normal", "parameter":"Elev-Pool", "base_parameter":"Elev", "tsid":"EMD.Elev-Pool.Inst.0.Bottom of Normal", "latest_value":904, "units":"ft", "units_long_name":"Feet", "type":"CONSTANT" }, { "slug":"elev.streambed", "label":"Streambed", "parameter":"Elev-Pool", "base_parameter":"Elev", "tsid":"EMD.Elev-Pool.Inst.0.Streambed", "latest_value":904, 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"slug":"stor.streambed", "label":"Streambed", "parameter":"Stor", "base_parameter":"Stor", "tsid":"EMD.Stor.Inst.0.Streambed", "latest_value":0, "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":"EMD.Stor.Inst.0.Top of Flood", "latest_value":12800, "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":"EMD.Stor.Inst.0.Top of Normal", "latest_value":0, "units":"ac-ft", "units_long_name":"Acre-feet", "type":"CONSTANT" } ], "id":550191, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":63, "damLength":1100, "distance":null, "drainageArea":44, "eapId":1, "dsacAssignedDate":"2024-07-11T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-12-20T12:00:00.000Z", "eapLastRevDate":"2019-05-01T12:00:00.000Z", "enforcementAuthorityId":1, "federalId":"NH00005", "oldFederalId":"NH00005", "hazardId":4, "hydraulicHeight":57, "inspectionAuthorityId":1, "inspectionDate":"2023-06-06T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":1, "latitude":42.893949235, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-71.986401209, "maxDischarge":17800, "maxStorage":31600, "nidHeight":63, "nidStorage":31600, "normalStorage":150, "numberOfLocks":0, "operationalStatusDate":"2014-05-02T12:00:00.000Z", "operationalStatusId":2, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":1, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The U.S. Army Corps of Engineers (USACE) built Edward MacDowell Dam (originally named the West Peterborough Dam) from 1948 to 1950 across the Nubanusit Brook. The dam holds back water during flood events to reduce the risk of downstream flooding on the Nubanusit Brook and Contoocook River. Edward MacDowell Dam normally holds a 7-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 2013, the dam has reduced damage caused by downstream flooding by more than $39.5 million.\n\nThe dam is made of compacted earth, rock, and gravel fill and is approximately 7 stories (67 feet) high. A 7-foot by 7-foot 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 at the 3.2 miles northeast 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 one third the length of a football field and approximately two stories below the top of the dam.", "riskCharSummary":"Dams do not eliminate all risk of flooding. USACE works to address all types of flood risk associated with the dam. Dams have limited capacity to store water. Water may be released through the dam to manage water levels up or downstream or to relieve pressure on the dam to maintain its structural integrity. Severe weather events that bring inconsistent or larger amounts of water into the system can also lead to dam releases or in some cases overwhelm and lead to issues occurring at a dam. \n\nAlthough Edward MacDowell Dam reduces the risk of flooding to downstream communities, the dam does not eliminate the risk of flooding. Edward MacDowell Dam is designed to manage peak flooding levels downstream without risking the structural integrity of the dam. The most likely scenario that could result in downstream flooding is high volume releases from Edward MacDowell Dam through the ungated spillway during high water events. This type of water release occurs when the reservoir's flood storage capacity is exceeded and excess water flows through the spillway. Water moving through the spillway during the largest expected flood in the watershed would put thousands of people at risk and flood waters could be as deep as a four-story building. While weather can be unpredictable, this type of event can often be predicted 1-2 days before flood waters would impact downstream communities. USACE will engage state emergency managers when such an event is forecasted and support actions to get people to safety.\n\nUSACE completed a risk assessment in 2023 and classified the risks associated with the Edward MacDowell Dam as low. This classification is based on the large population that lives immediately downstream of the dam in Peterborough, NH as well as other communities downstream. Three unlikely, but devastating scenarios that would produce significant downstream flooding are breach of the dam due to water flowing over the top of the dam; breach due to flow over the top of the dike, or scour of the impervious core into the bedrock below. In the case of an extremely rare and large rain event, water could potentially flow over the top of the dam or the dike, which could cause erosion of the earthen embankment, and breach of the dam or dike. In addition, it is possible, but very unlikely, that during a high pool, the soil of the embankment could move into cracks in the bedrock, which could eventually cause the crest to settle. In these scenarios, Peterborough, HIllsborough, Henniker, and Manchester, NH, along with other communities along the Merrimack River, would be the most impacted with a potential incremental life loss of between 100 to 1000 people. Downstream flooding in Peterborough would occur less than an hour after of breach and the rapidly moving water could be as deep as 25 feet, destroying buildings and critical infrastructure. In addition, some evacuation routes would be under water, increasing evacuation distances.", "riskManagementMeasures":"USACE manages dam-related flood risks by continually monitoring the condition and health of the dam, prioritizing activities that will most impact the risks, and engaging upstream and downstream emergency managers and members of the public to raise awareness of the dam and support actions to prepare and be ready to respond in the case of a dam-related emergency. USACE works closely with local emergency managers to share what is known about the dam and support the development of local emergency and evacuation plans. USACE regularly updates the emergency action plan for the dam. Regular maintenance and repairs are performed as needed to keep the dam functioning properly. \n\nEdward MacDowell Dam is staffed full time. During high pools, it is inspected on a daily basis. When the pool continues to rise, engineers conduct a site visit to evaluate dam performance. Geotechnical instrumentation data is reviewed regularly during normal pools and more frequently during high pools.", "riverName":"NUBANUSIT BROOK", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":100, "stateFedId":"NH00005", "stateRegulatoryAgency":"NH DES", "stateRegulatedId":1, "structuralHeight":63, "submitDate":"2023-02-16T17:25:35.553Z", "surfaceArea":165, "volume":210000, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1950, "congDist":"Congressional District 02, New Hampshire", "city":"PETERBOROUGH", "county":"Hillsborough", "aiannh":null, "websiteUrl":"https://www.nae.usace.army.mil/Missions/Civil-Works/Flood-Risk-Management/New-Hampshire/Edward-Mac/", "coreTypeIds":"3", "damTypeIds":"8", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":"West Peterborough Dam", "foundationTypeIds":"1;3", "nonFederalDamOnFederalId":0, "designerNames":"CENAE", "otherNames":"Edward MacDowell Lake", "ownerNames":"USACE - New England District", "ownerTypeIds":"3", "primaryDamTypeId":8, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;5", "dsacId":4, "femaRegion":"1", "lastEapExcerDate":"2024-09-05T12:00:00.000Z", "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":"010700", "doi_region":null, "doi_region_name":"North Atlantic-Appalachian", "doi_region_number":1 }, "id":8059021, "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/8059021?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/8059021?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/8059021?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }