{ "bbox":null, "type":"Feature", "geometry":{ "bbox":null, "type":"Point", "coordinates":[ -95.62333, 29.79111 ] }, "properties":{ "provider":"SWG", "code":"ADDT2", "slug":"addt2", "elevation":0.0, "horizontal_datum":"NAD27", "vertical_datum":"NAVD88", "state":"TX", "kind":"PROJECT", "nearest_city":"Houston", "public_name":"Addicks Reservoir", "location_code":130049, "nsid":null, "aliases":{ "NIDID":"TX00018", "USGS Station Number":"08073000" }, "timeseries":[ { "tsid":"ARPT2.Stage.Inst.1Hour.0.Decodes-Rev", "label":"Stage Tailwater", "base_parameter":"Stage", "parameter":"Stage", "unit":"ft", "unit_long_name":"Feet", "latest_time":"2026-04-14T20:00:00Z", "latest_value":61.41, "delta24h":null, "sort_order":5, "results":null }, { "tsid":"ADDT2.Stor.Inst.1Hour.0.Decodes-Rev", "label":"Conservation Storage", "base_parameter":"Stor", "parameter":"Stor", "unit":"ac-ft", "unit_long_name":"Acre-feet", "latest_time":"2026-04-14T21:00:00Z", "latest_value":5206.03, "delta24h":null, 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}, { "slug":"stor.top of conservation", "label":"Top of Conservation", "parameter":"Stor", "base_parameter":"Stor", "tsid":"ADDT2.Stor.Inst.0.Top of Conservation", "latest_value":2.06, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of flood", "label":"Top of Flood", "parameter":"Stor", "base_parameter":"Stor", "tsid":"ADDT2.Stor.Inst.0.Top of Flood", "latest_value":199643, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of inactive", "label":"Top of Inactive", "parameter":"Stor", "base_parameter":"Stor", "tsid":"ADDT2.Stor.Inst.0.Top of Inactive", "latest_value":2, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of limits", "label":"Top of Limits", "parameter":"Stor", "base_parameter":"Stor", "tsid":"ADDT2.Stor.Inst.0.Top of Limits", "latest_value":127591, "units":"ac-ft", "units_long_name":"Acre-feet" }, { "slug":"stor.top of standard", "label":"Top of Standard", "parameter":"Stor", "base_parameter":"Stor", "tsid":"ADDT2.Stor.Inst.0.Top of Standard", "latest_value":193956, "units":"ac-ft", "units_long_name":"Acre-feet" } ], "id":550029, "associatedStructuresCount":0, "conditionAssessDate":null, "conditionAssessDetail":null, "conditionAssessId":6, "damHeight":49, "damLength":61166, "distance":1, "drainageArea":136, "eapId":1, "dsacAssignedDate":"2023-06-12T12:00:00.000Z", "eapMeetsGuidelinesId":1, "emergencyContactsUpdated":"2025-04-14T12:00:00.000Z", "eapLastRevDate":"2022-09-19T12:00:00.000Z", "enforcementAuthorityId":0, "federalId":"TX00018", "oldFederalId":"TX00018", "hazardId":4, "hydraulicHeight":41, "inspectionAuthorityId":0, "inspectionDate":"2023-11-17T12:00:00.000Z", "inspectionFrequency":1, "jurisdictionAuthorityId":0, "latitude":29.7906235240001, "lengthOfLocks":0, "secondaryLengthOfLocks":null, "longitude":-95.625091486, "maxDischarge":7850, "maxStorage":199643, "nidHeight":52, "nidStorage":199643, "normalStorage":0, "numberOfLocks":0, "operationalStatusDate":"2023-06-12T12:00:00.000Z", "operationalStatusId":3, "originalDesignerName":null, "otherStructureId":null, "permittingAuthorityId":0, "politicalPartyId":null, "privateDamId":null, "projectDescription":"Addicks Dam was built by the U.S. Army Corps of Engineers (USACE) in 1948. The dam is approximately 17 miles west of downtown Houston, Texas, and stretches 11 miles across Langham Creek. Addicks Dam is operated in conjunction with Barker Dam, less than a mile away. Addicks Dam is to the north of Interstate 10 and Barker on the south of Interstate 10. Addicks and Barker dams both release into Buffalo Bayou and are in the same watershed. Together these dams reduce flood risk downstream along Buffalo Bayou and in significantly developed residential and economically critical commercial areas of Houston, including downtown. \n\nAddicks Dam consists of three main structural components: a 48 -foot tall earthen embankment, the gated water control structure, and the emergency spillways. The embankment stores water runoff in the reservoir throughout the year. The water control structure consists of three gated outlets that can release a total of approximately 8,000 cubic feet of water each second; that looks like 3.5 million gallons of water passing every minute.\n\nDuring normal operations, USACE holds water behind the embankments of both Addicks and Barker dams and then releases water through the gated outlets in a controlled manner. USACE manages the capacity of the two reservoirs to remain within 20 percent of each other to help balance the total volume of water released downstream and ensures the downstream bayou below the dam can handle the additional releases from both dams. This coordination helps keep Buffalo Bayou within its banks; reduces threats to life safety and property downstream; and, reduces the potential of flooding to the communities surrounding the reservoirs when water levels exceed the capacity for which the reservoirs were designed. \n\nThe emergency spillways at both the Addicks and Barker dams consist of concrete slabs located at each end of the dams. These spillways pass high volumes of water during extreme rainfall events -- much like the overflow holes in a sink -- to keep water from overtopping the earthen embankment. During extreme floods like Hurricane Harvey, USACE may release water through the outlets even though streams and rivers downstream may have already reached or exceeded their capacity.", "riskCharSummary":"Addicks Dam significantly reduces - but does not eliminate - flood risks. Flooding can still occur in surrounding communities and watersheds. Large storm events may cause more runoff than Addicks Dam can store (the most recent example of this was during Hurricane Harvey in 2017). \n\nThe reservoir can store stormwater inflow within the boundaries of the government-owned land from what is referred to as a \"71-year flood\", which means there is a 1.4-percent chance of such an event happening every year. Although larger rain events like Hurricane Harvey are less likely to occur, damage can be catastrophic during these large floods. The greater stormwater inflow could inundate larger areas, leading to higher stages, or elevation, in the reservoir and areas above government-owned land. The upstream flooding may damage and destroy buildings, roads, and bridges, and could potentially result in the loss of life. This starts to happen when pools reach an elevation of 103 feet North American Vertical Datum 88 (NAVD*), which is before water flows around or over the emergency spillway. Water begins to flow around and over the emergency spillways when pools reach about 108 feet NAVD 88, with peak pool levels of 115 feet NAVD possible. Residents and property owners should check https://www.swg.usace.army.mil/Missions/Dam-Safety-Program/About-The-Reservoirs/Addicks-and-Barker-Potential-Flood-Maps/ and their home survey to evaluate their personal risk. Refer to the NID inundation maps here for additional details.\n\nIn 2013, and again in 2020, USACE completed risk assessments on the Addicks Dam to determine potential threats to its ability to reduce flood risks. Assessment results classified the risk as \"high\" based on the consequences of flooding to the large populations living and working downstream of the dam in the event of dam failure and upstream in the event of extreme floods. Although it is considered extremely unlikely, a failure of the Addicks Dam would include catastrophic flooding, widespread economic impacts and significant loss of life downstream.\n\nDam safety concerns identified in the 2013 risk assessment have been addressed by the construction of the new water control structure and cutoff wall completed in 2020. The current risk at the dam is driven by the potential loss or movement of emergency spillway concrete slabs and breach of spillways at high-water elevations due to significant water pressures beneath the slabs. This increased water pressure could cause the slabs to pop up allowing water to more easily displace the slab and erode the soil beneath.\n\n*NAVD is the North American Vertical Datum. It is a point of reference on the earth used for measuring locations and elevations.", "riskManagementMeasures":"To ensure Addicks and Barker dams can continue reducing flood risks, USACE operates the dams in accordance with a water control manual and consideration of current flow conditions, precipitation, and forecasts. USACE also coordinates operational decisions closely with the National Weather Service, Harris County Flood Control District, U.S. Geological Survey, and other agencies related to conditions both upstream and downstream of the dams. USACE updates the dams' Emergency Action Plans annually and practices emergency response efforts with state and local emergency management agencies and key stakeholders. Obtain additional information at https://www.swg.usace.army.mil/Missions/Dam-Safety-Program/ during extreme floods. \n\nUSACE recently constructed a new outlet structure to help reduce risks from foundation seepage and eliminate the instability of the original outlets at Addicks Dam. In addition, USACE continues to rehabilitate the concrete spillways by filling in cracks and joints to reduce their risk of failing at both dams. USACE is currently undertaking the Buffalo Bayou Resiliency and Tributary Study to evaluate potential additional actions, including those at the Addicks Dam itself, to reduce flood risks upstream and downstream of Addicks and Barker dams. \n\nUSACE also regularly inspects the Addicks Dam and routinely re-assesses its risk. Dam safety professionals continuously monitor both the Addicks and Barker dams during high water events and are prepared to respond if performance issues arise during any event. In the case of an emergency, USACE will communicate with local and state emergency managers, in accordance with its Emergency Action Plan, to ensure the proper precautions are taken and that notification is provided to potentially impacted communities.", "riverName":"SOUTH MAYDE CREEK", "separateStructuresCount":0, "sourceAgency":"US Army Corps of Engineers", "spillwayTypeId":3, "spillwayWidth":18530, "stateFedId":"TX00018", "stateRegulatoryAgency":null, "stateRegulatedId":0, "structuralHeight":49, "submitDate":"2023-02-16T17:25:37.985Z", "surfaceArea":1, "volume":4793717, "widthOfLocks":0, "secondaryWidthOfLocks":null, "yearCompleted":1948, "congDist":"Congressional District 38, Texas", "city":"HOUSTON", "county":"Harris", "aiannh":null, "websiteUrl":"https://www.swg.usace.army.mil/Missions/Dam-Safety-Program/", "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":"CESWG", "otherNames":null, "ownerNames":"USACE - Galveston District", "ownerTypeIds":"3", "primaryDamTypeId":9, "primaryOwnerTypeId":3, "primaryPurposeId":9, "purposeIds":"9;5", "dsacId":2, "femaRegion":"6", "lastEapExcerDate":"2024-07-02T12:00:00.000Z", "dataUpdated":"2025-07-16T12:00:00.000Z", "usaceDistrict":"Galveston District", "noConsequencesId":0, "secretaryAgricultureBuiltId":null, "nrcsWatershedAuthorizationId":null, "isAssociatedStructureId":"No", "fedRegulatedId":"Yes", "inundationNidAddedId":1, "damStatusId":2, "huc06":"120401", "doi_region":"ART", "doi_region_name":"Arkansas-Rio Grande-Texas Gulf", "doi_region_number":6 }, "id":130049, "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/130049?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/130049?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr/items/130049?f=html" }, { "rel":"collection", "type":"application/json", "title":"USACE Access2Water API", "href":"https://api.wwdh.internetofwater.app/collections/usace-edr" } ] }