{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -96.46532, 33.03236 ] }, "properties":{ "provider":"SWF", "code":"LVNT2", "slug":"lvnt2", "elevation":0.0, "horizontal_datum":"", "vertical_datum":"NGVD29", "state":"TX", "kind":"PROJECT", "nearest_city":"Wylie, TX", "public_name":"Lavon Lake", "location_code":428048, "nsid":null, "aliases":{ "NID Dam Name":"LAVON LAKE", "NIDID":"TX00007" }, "timeseries":[ { "tsid":"LVNT2.Flow-Out.Inst.1Hour.0.Rev-SWF-REGI", "label":"Outflow", "base_parameter":"Flow", "parameter":"Flow-Out", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-04-14T22:00:00Z", "latest_value":1.0, "delta24h":null, "sort_order":7, "results":null }, { "tsid":"LVNT2.Elev.Inst.1Hour.0.Decodes-Rev", "label":"Elevation", "base_parameter":"Elev", "parameter":"Elev", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":492.49, "delta24h":null, "sort_order":1, "results":null }, { "tsid":"LVNT2.Precip-INC.Total.~1Day.1Day.Best-SWF", "label":"Precipitation", "base_parameter":"Precip", "parameter":"Precip-INC", "unit":"in", "unit_long_name":"Inches", "latest_time":"2026-04-14T13:00:00Z", "latest_value":0.0, "delta24h":null, "sort_order":16, "results":null }, { "tsid":"LVNT2.Stor.Inst.1Hour.0.Decodes-Rev", "label":"Conservation Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":419993.48, "delta24h":null, "sort_order":13, "results":null }, { "tsid":"LVNT2.Stor.Inst.1Hour.0.Decodes-Rev", "label":"Flood Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T22:00:00Z", "latest_value":419993.48, "delta24h":null, "sort_order":11, "results":null }, { "tsid":"LVNT2.Flow-In.Ave.~1Day.1Day.Computed-SWF-REGI", "label":"Inflow", "base_parameter":"Flow", "parameter":"Flow-In", "unit":"cfs", "unit_long_name":"Cubic feet per second", "latest_time":"2026-04-14T05:00:00Z", "latest_value":579.3, "delta24h":null, "sort_order":6, "results":null } ], "name":"Lavon Lake", "hasResopsAverages":"true", "nidId":"TX00007", "nidid":"", "levels":[ { "slug":"elev.bottom of inactive", "label":"Bottom of Inactive", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Bottom of Inactive", "latest_value":448, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.design capacity", "label":"Design Capacity", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Design Capacity", "latest_value":509, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.maximum tailwater", "label":"Maximum Tailwater", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Maximum Tailwater", "latest_value":471, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.spillway crest", "label":"Spillway Crest", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Spillway Crest", "latest_value":475.5, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.streambed", "label":"Streambed", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Streambed", "latest_value":433, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of conservation", "label":"Top of Conservation", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Top of Conservation", "latest_value":492, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of dam", "label":"Top of Dam", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Top of Dam", "latest_value":514, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of flood", "label":"Top of Flood", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Top of Flood", "latest_value":503.5, "units":"ft", "units_long_name":"Feet" }, { "slug":"elev.top of inactive", "label":"Top of Inactive", "parameter":"Elev", "base_parameter":"Elev", "tsid":"LVNT2.Elev.Inst.0.Top of Inactive", "latest_value":453, "units":"ft", "units_long_name":"Feet" }, { "slug":"stor.bottom of inactive", "label":"Bottom of Inactive", "parameter":"Stor", "base_parameter":"Stor", "tsid":"LVNT2.Stor.Inst.0.Bottom of Inactive", "latest_value":0, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.spillway crest", "label":"Spillway Crest", "parameter":"Stor", "base_parameter":"Stor", "tsid":"LVNT2.Stor.Inst.0.Spillway Crest", "latest_value":178300, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.streambed", "label":"Streambed", "parameter":"Stor", "base_parameter":"Stor", "tsid":"LVNT2.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":"LVNT2.Stor.Inst.0.Top of Conservation", "latest_value":409360, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"LVNT2.Stor.Inst.0.Top of Flood", "latest_value":701028, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of inactive", "label":"Top of Inactive", "parameter":"Stor", "base_parameter":"Stor", "tsid":"LVNT2.Stor.Inst.0.Top of Inactive", "latest_value":2972, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":550037, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":81, "damLength":19493, "distance":null, "drainageArea":770, "eapId":1, "dsacAssignedDate":"2018-05-14T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2024-10-01T12:00:00.000Z", "eapLastRevDate":"2020-11-23T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"TX00007", "oldFederalId":"TX00007", "hazardId":4, "hydraulicHeight":76, "inspectionAuthorityId":0, "inspectionDate":"2022-02-16T12:00:00.000Z", "inspectionFrequency":5, "jurisdictionAuthorityId":0, "latitude":33.0323906310001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-96.468576755, "maxDischarge":357700, "maxStorage":1020500, "nidHeight":81, "nidStorage":1020500, "normalStorage":456500, "numberOfLocks":0, "operationalStatusDate":"2018-05-14T12:00:00.000Z", "operationalStatusId":1, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"The United States Army Corps of Engineers (USACE) completed construction of Lavon Dam in September 1953 in accordance with the River and Harbor Act approved 2 March 1945 (Public Law 14, 79th Congress, 1st Session). Lavon Dam was modified in 1974 based on the need for increased flood protection and water conservation authorized in the Flood Control Act of 1962, approved 23 October 1962 (Public Law 874, 87th Congress, 2nd Session, House Document No. 554). Lavon Dam was built on the East Fork of the Trinity River, to reduce the risk of flooding to the downstream Texas cities of Bardwell, Corsicana, and adjacent towns and counties. It is located 20 miles southeast of the City of McKinney in Collin County, Texas. Lavon Dam consists of earthen embankment sections that serves as the main water barrier and a controlled spillway to make discharges when water levels within the reservoir exceed the available flood storage. The main embankment is made up of soil and rock and is approximately 81 feet (about 8 stories) high at a crest elevation of 514.0-feet (NAVD88 vertical datum control). The dam is nearly four miles of earthen embankment except for the spillway located along the east end of the floodplain embankment. The spillway crest is at elevation 475.5-feet NAVD88 and includes a gated structure controlled by twelve radial arm lifting floodgates called Tainter gates, each measuring 40 feet by 28 feet and for a net opening of 480 feet across. The spillway can pass almost 3 million gallons per second, or enough water to flood a football field more than 6 feet deep every second. The reservoir is kept at or below the conservation pool elevation of 492.0-feet NAVD88 for most of the year. When heavy rains occur, surface water runoff is stored in the reservoir until the swollen streams and rivers below the dam recede and can handle the release of stored water minimizing loss of life, property, and negative impacts to the environment. Sometimes water must be released to protect the dam\u2019s integrity even though these streams and rivers may have already reached or exceeded their capacity. Although reducing flood risk is the project\u2019s primary focus, the dam also provides significant water supply to nearby communities and provides unique recreation opportunities. These benefits significantly improve the quality of life in the area.", "riskCharSummary":"Although Lavon Dam reduces the risk of flooding to downstream communities, the dam does not eliminate the risk of flooding. The most likely scenario that could result in downstream flooding due to floodwaters passed through the dam are high volume releases from the operation of Lavon Dam during high water events. These surcharge operational releases occur when the reservoir's flood storage capacity is exceeded, requiring opening of Tainter gates and causing flooding downstream of the dam and at Lake Ray Hubbard, immediately downstream. Lavon Dam is designed to reduce the peak flooding levels downstream without risking the structural integrity of the dam. Generally, the Trinity River's large floods are long-duration type lasting weeks or even months; however, it is possible that large peak and volume floods could occur in about two weeks duration. Despite the flood reduction benefits the dam provides, very rare, severe storms could still produce high surcharge releases with the potential to impact the communities of Wylie, Rockwall, Rowlett, Forney, Mesquite, and Seagoville.\n\nIn April 2017, the United States Army Corps of Engineers (USACE) completed a risk assessment to evaluate the potential hazards to the dam, expected performance, and associated consequences. The risk assessment classified the risk associated with Lavon Dam as low. Risk for Lavon Dam is driven by the potential for water from the reservoir to seep through the earthen embankment at the ends of the dam causing voids as the soil erodes and by water flowing over the top of the dam, potentially leading to erosion of the embankment and an eventual dam breach. While this event is unlikely, consequences include the potential for loss of life. The largest impacts would be in Mesquite, Texas, located approximately 28 river miles below the dam. Lake Ray Hubbard is located 4 miles downstream and is impounded by Rockwall-Forney Dam (NID ID TX00837), which is located 24 miles downstream. Lake Ray Hubbard cannot retain much flood water and would have to make releases through the dam\u2019s fourteen Tainter gates to avoid exceeding capacity. Small agricultural levees would overflow from the flood waters in the rural area further downstream. Although the downstream communities have well-practiced emergency action plans, local emergency managers who are aware of the unlikely potential for dam failure, and who meet regularly with USACE to discuss emergency response to flood events, breach of the dam could result in major flooding downstream and include significant economic impacts and put lives at risk.", "riskManagementMeasures":"The United States Army Corps of Engineers (USACE) Fort Worth District continuously takes additional steps to reduce the risk to the public. This includes working closely with local emergency managers to encourage and support the development and update of local evacuation plans to maximize evacuation time and designated evacuation routes; regularly updating the Lavon Dam Emergency Action Plan; and conducting emergency exercises with state and local response teams. USACE conducts detailed inspections of the dam during both normal lake levels and increased surveillance during flood events to ensure the integrity of the structure. Instrumentation and monitoring systems allow USACE staff to monitor the dam for changing conditions that may not be seen at the surface. Regular maintenance and repairs are performed as needed to keep the dam functioning properly.", "riverName":"EAST FORK OF TRINITY RIVER", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":1, "spillwayWidth":480, "stateFedId":"TX00007", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":81, "submitDate":"2023-02-24T00:00:00.000Z", "surfaceArea":21400, "volume":5990655, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1952, "congDist":"Congressional District 03, Texas", "city":"ROCKWALL", "county":"Collin", "aiannh":null, "websiteUrl":"https://www.swf-wc.usace.army.mil/lavon/", "coreTypeIds":"3", "damTypeIds":"8", "fedConstructionIds":"1", "fedDesignIds":"1", "fedFundingIds":"1", "fedInspectionIds":"1", "fedOperationIds":"1", "fedOtherIds":"1", "fedOwnerIds":"1", "fedRegulatoryIds":"1", "formerNames":null, "foundationTypeIds":"1;3", "nonFederalDamOnFederalId":0, "designerNames":"CESWF", "otherNames":"Lavon Lake", "ownerNames":"USACE - Fort Worth District", "ownerTypeIds":"3", "primaryDamTypeId":8, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;4;5;8", "dsacId":5, "femaRegion":"6", "lastEapExcerDate":"2024-10-02T12:00:00.000Z", "dataUpdated":"2025-07-16T12:00:00.000Z", "usaceDistrict":"Fort Worth District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"120301", "doi_region":"ART", "doi_region_name":"Arkansas-Rio Grande-Texas Gulf", "doi_region_number":6, "thirtyYearAverage":488.3141, "tenthPercentile":358.2311, "ninetiethPercentile":614.6454 }, "id":428048, "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/428048?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/428048?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/428048?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }